Generation of a drug-induced renal injury list to facilitate the development of new approach methodologies for nephrotoxicity

Drug-induced renal injury (DIRI) causes >1.5 million adverse events annually in the USA alone. Although standard biomarkers exist for DIRI, they lack the sensitivity or specificity to detect nephrotoxicity before the significant loss of renal function. In this study, we describe the creation of DIRIL - a list of drugs associated with DIRI and nephrotoxicity - from two literature datasets with DIRI annotation, confirmed using FDA drug labeling. DIRIL comprises 317 orally administered drugs covering all 14 anatomical, therapeutic and chemical (ATC) classification categories. Of the 317 drugs, 171 were DIRI-positive and 146 were DIRI-negative. DIRIL will be a relevant and invaluable resource for discovery of new approach methods (NAMs) to predict the occurrence and possible severity of DIRI earlier in drug development.

Evaluation of in vitro effects of ifosfamide drug on mitochondrial functions using isolated mitochondria obtained from vital organs

Mitochondrial toxicity has been shown to contribute to a variety of organ toxicities such as, brain, heart, kidney, and liver. Ifosfamide (IFO) as an anticancer drug, is associated with increased risk of neurotoxicity, cardiotoxicity nephrotoxicity, hepatotoxicity, and hemorrhagic cystitis. The aim of this study was to evaluate the direct effect of IFO on isolated mitochondria obtained from the rat brain, heart, kidney, and liver. Mitochondria were isolated with mechanical lysis and differential centrifugation from different organs and treated with various concentrations of IFO. Using biochemical and flowcytometry assays, we evaluated mitochondrial succinate dehydrogenase (SDH) activity, mitochondrial swelling, lipid peroxidation, reactive oxygen species (ROS) production, and mitochondrial membrane potential (MMP). Our data showed that IFO did not cause deleterious alterations in mitochondrial functions, mitochondrial swelling, lipid peroxidation ROS formation, and MMP collapse in mitochondria isolated from brain, heart, kidney, and liver. Altogether, the data showed that IFO is not directly toxic in mitochondria isolated from brain, heart, kidney, and liver. This study proved that mitochondria alone does not play the main role in the toxicity of IFO, and suggests to reduce the toxicity of this drug, other pathways resulting in the production of toxic metabolites should be considered.

Organ wide toxicological assessment of common edible herbs and their mixtures as used in home remedies

The use of home remedies for medicinal purposes, most of which are edible plants has continued to be a practice in many homes. However, there has been an increasing report of chronic use with lethal effect. Among the commonly used herbal/ medicinal plants were ginger, garlic and lemon. These were seen to be prevalent across continents with brewing and crude extraction being the most means of consumption. This study investigated the organ wide toxicity of this extract following chronic consumption of crude extract. Twenty-five albino Wister rats, five in each group were used for this experiment. Each animal received 0.5ml/kg body weight of either ginger extract, garlic extract, lemon juice, or a mixture of equal volumes of all three extract (v/v) respectively twice daily for seven (7) days. Statistics were represented as ±SE; P≤0.05 was considered significant. Previous studies have shown that moderate consumption of these medicinal plants were beneficial and have shown no deleterious effect. This study observed no change in the weight of the experimental animals. The weight of the animals continued to increase except for the group that received lemon and the mixture, but these were not significant. It was observed that chronic consumption induced organ wide toxicity to include the liver, kidney, intestinal epithelium, stomach, and pancreas. These were shown to alter tissue architecture and the cell morphology. Packed cell volume was reduced in the lemon and the group that received a combination of all extracts (p=o.03). Blood differentials showed changes in levels. An elevated basophil level was observed in ginger and garlic (p<0.0001; p=0.0006). Monocyte levels increased progressively across each group when compared to the control with the most elevated level seen in the group that received the mixture (p<0.0001). Lymphocyte count was reduced across all the groups that received the extract except for animals that received ginger. This study suggests the application of caution among users of these medicinal plants and continues to draw attention to the need for harmonization and standardization of safe use doses.

against doxorubicin-induced organ toxicity in EAC-mediated solid tumor-induced mice

Background and objective: Doxorubicin is extensively utilized chemotherapeutic drug, and it causes damage to the heart, liver, and kidneys through oxidative stress. Theobroma cacao L (cocoa) is reported to possess protective effects against several chemical-induced organ damages and also acts as an anticancer agent. The study aimed to determine whether the administration of cocoa bean extract reduces doxorubicin-induced organ damage in mice with Ehrlich ascites carcinoma (EAC) without compromising doxorubicin efficacy. Methodology: Multiple in vitro methods such as cell proliferation, colony formation, chemo-sensitivity, and scratch assay were carried out on cancer as well as normal cell lines to document the effect of cocoa extract (COE) on cellular physiology, followed by in vivo mouse survival analysis, and the organ-protective effect of COE on DOX-treated animals with EAC-induced solid tumors was then investigated. In silico studies were conducted on cocoa compounds with lipoxygenase and xanthine oxidase to provide possible molecular explanations for the experimental observations. Results: In vitro studies revealed potent selective cytotoxicity of COE on cancer cells compared to normal. Interestingly, COE enhanced DOX potency when used in combination. The in vivo results revealed reduction in EAC and DOX-induced toxicities in mice treated with COE, which also improved the mouse survival time; percentage of lifespan; antioxidant defense system; renal, hepatic, and cardiac function biomarkers; and also oxidative stress markers. COE reduced DOX-induced histopathological alterations. Through molecular docking and MD simulations, we observed chlorogenic acid and 8'8 methylenebiscatechin, present in cocoa, to have the highest binding affinity with lipoxygenase and xanthine oxidase, which lends support to their potential in ameliorating oxidative stress. Conclusion: The COE reduced DOX-induced organ damage in the EAC-induced tumor model and exhibited powerful anticancer and antioxidant effects. Therefore, COE might be useful as an adjuvant nutritional supplement in cancer therapy.

Three-dimensional (3D) cell culture studies: a review of the field of toxicology

Traditional two-dimensional (2D) cell culture employed for centuries is extensively used in toxicological studies. There is no doubt that 2D cell culture has made significant contributions to toxicology. However, in today's world, it is necessary to develop more physiologically relevant models. Three-dimensional (3D) cell culture, which can recapitulate the cell's microenvironment, is, therefore, a more realistic model compared to traditional cell culture. In toxicology, 3D cell culture models are a powerful tool for studying different tissues and organs in similar environments and behave as if they are in in vivo conditions. In this review, we aimed to present 3D cell culture models that have been used in different organ toxicity studies. We reported the results and interpretations obtained from these studies. We aimed to highlight 3D models as the future of cell culture by reviewing 3D models used in different organ toxicity studies.

A review of the protective effects of chlorogenic acid against different chemicals

Chlorogenic acid (CGA) is a naturally occurring non-flavonoid polyphenol found in green coffee beans, teas, certain fruits, and vegetables, that exerts antiviral, antitumor, antibacterial, and antioxidant effects. Several in vivo and in vitro studies have demonstrated that CGA can protect against toxicities induced by chemicals of different classes such as fungal/bacterial toxins, pharmaceuticals, metals, pesticides, etc., by preservation of cell survival via reducing overproduction of nitric oxide and reactive oxygen species and suppressed pro-apoptotic signaling. CGA antioxidant effects mediated through the Nrf2-heme oxygenase-1 signaling pathway were shown to enhance the levels of antioxidant enzymes such as superoxide dismutase, catalase, glutathione-S-transferases, glutathione peroxidase, and glutathione reductase as well as glutathione content. Also, CGA could suppress inflammation via inhibition of toll-like receptor 4 and MyD88, and the phosphorylation of inhibitor of kappa B and p65 subunit of NF-κB, resulting in diminished levels of downstream inflammatory factors including interleukin (IL)-1 β, IL-6, tumor necrosis factor-α, macrophage inflammatory protein 2, cyclooxygenase-2, and prostaglandin E2. Moreover, CGA inhibited apoptosis by reducing Bax, cytochrome C, and caspase 3 and 9 expression while increasing Bcl-2 levels. The present review discusses several mechanisms through which CGA may exert its protective role against such agents. Chemical and natural toxic agents affect human health. Phenolic antioxidant compounds can suppress free radical production and combat these toxins. Chlorogenic acid is a plant polyphenol present in the human diet and exerts strong antioxidant properties that can effectively help in the treatment of various toxicities.

Zebrafish Embryos and Larvae as Alternative Animal Models for Toxicity Testing

Prerequisite to any biological laboratory assay employing living animals is consideration about its necessity, feasibility, ethics and the potential harm caused during an experiment. The imperative of these thoughts has led to the formulation of the 3R-principle, which today is a pivotal scientific standard of animal experimentation worldwide. The rising amount of laboratory investigations utilizing living animals throughout the last decades, either for regulatory concerns or for basic science, demands the development of alternative methods in accordance with 3R to help reduce experiments in mammals. This demand has resulted in investigation of additional vertebrate species displaying favourable biological properties. One prominent species among these is the zebrafish (Danio rerio), as these small laboratory ray-finned fish are well established in science today and feature outstanding biological characteristics. In this review, we highlight the advantages and general prerequisites of zebrafish embryos and larvae before free-feeding stages for toxicological testing, with a particular focus on cardio-, neuro, hepato- and nephrotoxicity. Furthermore, we discuss toxicokinetics, current advances in utilizing zebrafish for organ toxicity testing and highlight how advanced laboratory methods (such as automation, advanced imaging and genetic techniques) can refine future toxicological studies in this species.

Multiorgan Crystal Deposition of an Amphoteric Drug in Rats Due to Lysosomal Accumulation and Conversion to a Poorly Soluble Hydrochloride Salt

Poor solubility of drug candidates mainly affects bioavailability, but poor solubility of drugs and metabolites can also lead to precipitation within tissues, particularly when high doses are tested. RO0728617 is an amphoteric compound bearing basic and acidic moieties that has previously demonstrated good solubility at physiological pH but underwent widespread crystal deposition in multiple tissues in rat toxicity studies. The aim of our investigation was to better characterize these findings and their underlying mechanism(s), and to identify possible screening methods in the drug development process. Main microscopic features observed in rat RO0728617 toxicity studies were extensive infiltrates of crystal-containing macrophages in multiple organs. Matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry revealed that these crystals contained the orally administered parent compound, and locality was confirmed to be intracytoplasmic and partly intralysosomal by electron microscopic examination. Crystal formation was explained by lysosomal accumulation of the compound followed by precipitation of the hydrochloride salt under physiological conditions in the lysosomes, which have a lower pH and higher chloride concentration in comparison to the cytosol. This study demonstrates that risk of drug precipitation can be assessed by comparing the estimated lysosomal drug concentration at a given dose with the solubility of the compound at lysosomal conditions.

Nonspherical Metal-Based Nanoarchitectures: Synthesis and Impact of Size, Shape, and Composition on Their Biological Activity

Metal-based nanoentities, apart from being indispensable research tools, have found extensive use in the industrial and biomedical arena. Because their biological impacts are governed by factors such as size, shape, and composition, such issues must be taken into account when these materials are incorporated into multi-component ensembles for clinical applications. The size and shape (rods, wires, sheets, tubes, and cages) of metallic nanostructures influence cell viability by virtue of their varied geometry and physicochemical interactions with mammalian cell membranes. The anisotropic properties of nonspherical metal-based nanoarchitectures render them exciting candidates for biomedical applications. Here, the size-, shape-, and composition-dependent properties of nonspherical metal-based nanoarchitectures are reviewed in the context of their potential applications in cancer diagnostics and therapeutics, as well as, in regenerative medicine. Strategies for the synthesis of nonspherical metal-based nanoarchitectures and their cytotoxicity and immunological profiles are also comprehensively appraised.

Establishment of patient-derived xenograft model of peritoneal mucinous carcinomatosis with signet ring cells and in vivo study on the efficacy and toxicity of intraperitoneal injection of 5-fluorouracil

BACKGROUND

Pseudomyxoma peritonei (PMP) is an indolent malignancy and insensitive to systemic chemotherapy. The authors established patient-derived xenograft (PDX) model of PMP, and evaluated the efficacy and toxicity of intraperitoneal (i.p.) administration of 5-fluorouracil (5-FU) in this model.

METHODS

Human PMP sample was collected to establish subcutaneous (s.c.) and i.p.

MODEL

In vivo study of i.p. injection of 5-FU was performed in i.p. model, with experimental peritoneal cancer index (ePCI) score and pathological examinations for evaluating the efficacy and toxicity.

RESULTS

Both s.c. and i.p. models were constructed. The average passage interval of s.c. model was 44.2 ± 5.2 days, and the i.p. model was characterized by disseminated solid tumor nodules in abdominal-pelvic cavity. Both models were diagnosed as peritoneal mucinous carcinomatosis with signet ring cells (PMCA-S). Immunohistochemical characteristics was similar to human. GNAS mutation was detected in both model and patient. In the in vivo study, average ePCI of treatment group was lower than control and vehicle group (P = .004). Histopathology revealed obvious tumor necrosis in treatment group, and decreased Ki67 positive rate (P = .010). In toxicity study, 5-FU significantly influenced body weight (P = .010) and 1 animal from treatment group died on day 14. Congestive splenomegaly was observed (88.9%). Hepatotoxicity presented as acidophilic body (55.6%), cholestasis (100%), bile canaliculus hyperplasia and obstruction (22.2%), and lymphocyte accumulation (77.8%).

CONCLUSIONS

PDX model of PMCA-S was established successfully, and i.p. 5-FU could inhibit tumor proliferation and progression, with decreased Ki67 positive rate and ePCI score. Hepatotoxicity was the main side effect.

Tacrine and its 7-methoxy derivate; time-change concentration in plasma and brain tissue and basic toxicological profile in rats

The search for tacrine derivatives, as potential Alzheimer´s disease treatment, is still being at the forefront of scientific efforts. 7-MEOTA was found to be a potent, centrally active acetylcholinesterase inhibitor free of the serious side effects observed for tacrine. Unfortunately, a relevant argumentation about pharmacokinetics and potential toxicity is incomplete; information about tacrine derivatives absorption and especially CNS penetration are still rare as well as detailed toxicological profile in vivo. Although the structural changes between these compounds are not so distinctive, differences in plasma profile and CNS targeting were found. The maximum plasma concentration were attained at 18^th min (tacrine; 38.20 ± 3.91 ng/ml and 7-MEOTA; 88.22 ± 15.19 ng/ml) after i.m. application in rats. Although the brain profiles seem to be similar; tacrine achieved 19.34 ± 0.71 ng/ml in 27 min and 7-MEOTA 15.80 ± 1.13 ng/ml in 22 min; the tacrine Kp (AUC_brain/AUC_plasma) fit 1.20 and was significantly higher than 7-MEOTA Kp 0.10. Administration of tacrine and 7-MEOTA showed only mild elevation of some biochemical markers following single p.o. application in 24 hours and 7 days. Also histopathology revealed only mild-to-moderate changes following repeated p.o. administration for 14 days. It seems that small change in tacrine molecule leads to lower ability to penetrate through the biological barriers. The explanation that lower p.o. acute toxicity of 7-MEOTA depends only on differences in metabolic pathways may be now revised to newly described differences in pharmacokinetic and toxicological profiles.

TRPs in Tox: Involvement of Transient Receptor Potential-Channels in Chemical-Induced Organ Toxicity-A Structured Review

Chemicals can exhibit significant toxic properties. While for most compounds, unspecific cell damaging processes are assumed, a plethora of chemicals exhibit characteristic odors, suggesting a more specific interaction with the human body. During the last few years, G-protein-coupled receptors and especially chemosensory ion channels of the transient receptor potential family (TRP channels) were identified as defined targets for several chemicals. In some cases, TRP channels were suggested as being causal for toxicity. Therefore, these channels have moved into the spotlight of toxicological research. In this review, we screened available literature in PubMed that deals with the role of chemical-sensing TRP channels in specific organ systems. TRPA1, TRPM and TRPV channels were identified as essential chemosensors in the nervous system, the upper and lower airways, colon, pancreas, bladder, skin, the cardiovascular system, and the eyes. Regarding TRP channel subtypes, A1, M8, and V1 were found most frequently associated with toxicity. They are followed by V4, while other TRP channels (C1, C4, M5) are only less abundantly expressed in this context. Moreover, TRPA1, M8, V1 are co-expressed in most organs. This review summarizes organ-specific toxicological roles of TRP channels.

Cyclosporine A disposition, hepatic and renal tolerance in Wistar rat

Cyclosporine A, a potent calcineurin inhibitor, has been widely used in organ transplantation and in the treatment of autoimmune diseases. It has, however, been shown to induce serious renal and hepatic side effects. The drug is also used in preclinical studies, but with little published information on the optimal dose and route of administration in rodents. Objectives of this study were to identify efficient and safe doses of cyclosporine A in rodent and to assess its effects on hepatic and renal functions. For this purpose, we tested the effects of different doses and administration routes of cyclosporine A (5, 2.5 and 1 mg/kg) administered during 28 days intraperitoneally, or by gastric feeding on Wistar rats. Our data indicate that rats injected intraperitoneally with 5 mg/kg/2d (every two days) exhibited trough cyclosporine A levels within known therapeutic range in human, but were subject to blood cyclosporine A accumulation, whereas the 5 mg/kg/d gavage resulted in only a small cyclosporine A accumulation over time. In both cases this accumulation was not deleterious to renal and hepatic functions, as shown by transaminase, urea, creatinine and bilirubin measurements.

Oxidative stress, inflammation, and DNA damage in multiple organs of mice acutely exposed to amorphous silica nanoparticles

The use of amorphous silica (SiO₂) in biopharmaceutical and industrial fields can lead to human exposure by injection, skin penetration, ingestion, or inhalation. However, the in vivo acute toxicity of amorphous SiO₂ nanoparticles (SiNPs) on multiple organs and the mechanisms underlying these effects are not well understood. Presently, we investigated the acute (24 hours) effects of intraperitoneally administered 50 nm SiNPs (0.25 mg/kg) on systemic toxicity, oxidative stress, inflammation, and DNA damage in the lung, heart, liver, kidney, and brain of mice. Lipid peroxidation was significantly increased by SiNPs in the lung, liver, kidney, and brain, but was not changed in the heart. Similarly, superoxide dismutase and catalase activities were significantly affected by SiNPs in all organs studied. While the concentration of tumor necrosis factor α was insignificantly increased in the liver and brain, its increase was statistically significant in the lung, heart, and kidney. SiNPs induced a significant elevation in pulmonary and renal interleukin 6 and interleukin-1 beta in the lung, liver, and brain. Moreover, SiNPs caused a significant increase in DNA damage, assessed by comet assay, in all the organs studied. SiNPs caused leukocytosis and increased the plasma activities of lactate dehydrogenase, creatine kinase, alanine aminotranferase, and aspartate aminotransferase. These results indicate that acute systemic exposure to SiNPs causes oxidative stress, inflammation, and DNA damage in several major organs, and highlight the need for thorough evaluation of SiNPs before they can be safely used in human beings.

Effect of aqueous leaves extract of Costus afer Ker Gawl (Zingiberaceae) on the liver and kidney of male albino Wistar rat

BACKGROUND

The use of medicinal plants in Nigeria has significantly increased over recent years as it is easily accessible, cheap and the strong belief that herbal remedies are natural and therefore non toxic.

AIMS

This study aims to investigate the sub-chronic toxicity (28-day) of the aqueous extract of Costus afer Ker Gawl leaves on the liver and kidney of male albino Wistar rats.

MATERIALS AND METHODS

A total of 20 male albino Wistar rats (113-205 g) divided into four groups of five weight-matched animals each, were used for the study. Group 1 received standard feed and water ad libitium and served as the control. Group 2, 3 and 4 received 375, 750 and 1125 mg/kg of aqueous extract of C. afer leaves respectively. The animals were sacrificed under ether anesthesia and the organs were harvested, weighed and histopathological studies carried out. The effect of C. afer on the hepatic biomarkers aspartate aminotransferase (AST), alanine aminotransferase (ALT); alkaline phosphatase (ALP); triglyceride (TG); total bilirubin (TB); conjugated bilirubin (CB); albumin (ALB) and kidney biomarkers urea, creatinine, sodium, potassium and bicarbonate were investigated.

STATISTICAL ANALYSIS

Data were evaluated using Mann Whitney. If P ≤ 0.05 groups were considered to be significantly different.

RESULTS

C. afer contained alkaloids, saponins, flavonoids, anthraquinones, cardiac glycosides, terpenoids, phenolic compounds and tannins. The average body, organ, relative weights, feed and fluid intake showed no significant changes (P > 0.05) when compared to the control. The liver function tests (ALT, ALP, AST, CB, TB and ALB) showed significant differences (P < 0.05) in the test groups when compared with the control while TG showed no statistical difference (P > 0.05). The kidney function tests (urea, creatinine, sodium, potassium and bicarbonate) showed no significant differences (P > 0.05) in the test groups when compared to the control.

CONCLUSION

Costus afer may be hepatotoxic but non-toxic to the kidney.

Cadmium-Induced Pathologies: Where Is the Oxidative Balance Lost (or Not)?

Over the years, anthropogenic factors have led to cadmium (Cd) accumulation in the environment causing various health problems in humans. Although Cd is not a Fenton-like metal, it induces oxidative stress in various animal models via indirect mechanisms. The degree of Cd-induced oxidative stress depends on the dose, duration and frequency of Cd exposure. Also the presence or absence of serum in experimental conditions, type of cells and their antioxidant capacity, as well as the speciation of Cd are important determinants. At the cellular level, the Cd-induced oxidative stress either leads to oxidative damage or activates signal transduction pathways to initiate defence responses. This balance is important on how different organ systems respond to Cd stress and ultimately define the pathological outcome. In this review, we highlight the Cd-induced oxidant/antioxidant status as well as the damage versus signalling scenario in relation to Cd toxicity. Emphasis is addressed to Cd-induced pathologies of major target organs, including a section on cell proliferation and carcinogenesis. Furthermore, attention is paid to Cd-induced oxidative stress in undifferentiated stem cells, which can provide information for future therapies in preventing Cd-induced pathologies.

High-density real-time PCR-based in vivo toxicogenomic screen to predict organ-specific toxicity

Toxicogenomics, based on the temporal effects of drugs on gene expression, is able to predict toxic effects earlier than traditional technologies by analyzing changes in genomic biomarkers that could precede subsequent protein translation and initiation of histological organ damage. In the present study our objective was to extend in vivo toxicogenomic screening from analyzing one or a few tissues to multiple organs, including heart, kidney, brain, liver and spleen. Nanocapillary quantitative real-time PCR (QRT-PCR) was used in the study, due to its higher throughput, sensitivity and reproducibility, and larger dynamic range compared to DNA microarray technologies. Based on previous data, 56 gene markers were selected coding for proteins with different functions, such as proteins for acute phase response, inflammation, oxidative stress, metabolic processes, heat-shock response, cell cycle/apoptosis regulation and enzymes which are involved in detoxification. Some of the marker genes are specific to certain organs, and some of them are general indicators of toxicity in multiple organs. Utility of the nanocapillary QRT-PCR platform was demonstrated by screening different references, as well as discovery of drug-like compounds for their gene expression profiles in different organs of treated mice in an acute experiment. For each compound, 896 QRT-PCR were done: four organs were used from each of the treated four animals to monitor the relative expression of 56 genes. Based on expression data of the discovery gene set of toxicology biomarkers the cardio- and nephrotoxicity of doxorubicin and sulfasalazin, the hepato- and nephrotoxicity of rotenone, dihydrocoumarin and aniline, and the liver toxicity of 2,4-diaminotoluene could be confirmed. The acute heart and kidney toxicity of the active metabolite SN-38 from its less toxic prodrug, irinotecan could be differentiated, and two novel gene markers for hormone replacement therapy were identified, namely fabp4 and pparg, which were down-regulated by estradiol treatment.