In Vitro Antineoplastic and Antiviral Activity and In Vivo Toxicity of Geum urbanum L. Extracts

This study evaluated the in vitro antineoplastic and antiviral potential and in vivo toxicity of twelve extracts with different polarity obtained from the herbaceous perennial plant Geum urbanum L. (Rosaceae). In vitro cytotoxicity was determined by ISO 10993-5/2009 on bladder cancer, (T-24 and BC-3C), liver carcinoma (HEP-G2) and normal embryonic kidney (HEK-293) cell lines. The antineoplastic activity was elucidated through assays of cell clonogenicity, apoptosis induction, nuclear factor kappa B p65 (NFκB p65) activation and total glutathione levels. Neutral red uptake study was applied for antiviral activity. The most promising G. urbanum extract was analyzed by UHPLC–HRMS. The acute in vivo toxicity analysis was carried out following OEDC 423. The ethyl acetate extract of aerial parts (EtOAc-AP) exhibited the strongest antineoplastic activity on bladder cancer cell lines (IC50 = 21.33–25.28 µg/mL) by inducing apoptosis and inhibiting NFκB p65 and cell clonogenicity. EtOAc and n-butanol extracts showed moderate antiviral activity against human adenovirus type 5 and human simplex virus type I. Seventy four secondary metabolites (gallic and ellagic acid derivatives, phenolic acids, flavonoids, etc.) were identified in EtOAc-AP by UHPLC–HRMS. This extract induced no signs of acute toxicity in liver and kidney specimens of H-albino mice in doses up to 210 mg/kg. In conclusion, our study contributes substantially to the detailed pharmacological characterization of G. urbanum, thus helping the development of health-promoting phytopreparations.

Galleria mellonella: The Versatile Host for Drug Discovery, In Vivo Toxicity Testing and Characterising Host-Pathogen Interactions

Larvae of the greater wax moth, Galleria mellonella, are a convenient in vivo model for assessing the activity and toxicity of antimicrobial agents and for studying the immune response to pathogens and provide results similar to those from mammals. G. mellonella larvae are now widely used in academia and industry and their use can assist in the identification and evaluation of novel antimicrobial agents. Galleria larvae are inexpensive to purchase and house, easy to inoculate, generate results within 24–48 h and their use is not restricted by legal or ethical considerations. This review will highlight how Galleria larvae can be used to assess the efficacy of novel antimicrobial therapies (photodynamic therapy, phage therapy, metal-based drugs, triazole-amino acid hybrids) and for determining the in vivo toxicity of compounds (e.g., food preservatives, ionic liquids) and/or solvents (polysorbate 80). In addition, the disease development processes are associated with a variety of pathogens (e.g., Staphylococcus aureus, Listeria monocytogenes, Aspergillus fumigatus, Madurella mycotomatis) in mammals are also present in Galleria larvae thus providing a simple in vivo model for characterising disease progression. The use of Galleria larvae offers many advantages and can lead to an acceleration in the development of novel antimicrobials and may be a prerequisite to mammalian testing.

The zebrafish embryo as an in vivo model for screening nanoparticle-formulated lipophilic anti-tuberculosis compounds

With the increasing emergence of drug-resistant Mycobacterium tuberculosis strains, new and effective antibiotics against tuberculosis (TB) are urgently needed. However, the high frequency of poorly water-soluble compounds among hits in high-throughput drug screening (HTS) campaigns is a major obstacle in drug discovery. Moreover, in vivo testing using conventional animal TB models such as mice is time-consuming and costly, and represents a major bottleneck in lead compound discovery and development. Here, we report the use of the zebrafish embryo TB model, to evaluate the in vivo toxicity and efficacy of five poorly water-soluble nitronaphthofuran derivatives, which were recently identified to possess anti-tuberculosis activity in vitro. To aid solubilization compounds were formulated in biocompatible polymeric micelles (PM). Three of the five PM-formulated nitronaphthofuran derivatives showed low toxicity in vivo, significantly reduced bacterial burden and improved survival in infected zebrafish embryos. We propose the zebrafish embryo TB-model as a quick and sensitive tool for evaluating in vivo toxicity and efficacy of new anti-TB compounds during early stages of drug development. Thus, this model is well suited to pinpoint promising compounds for further development.

Preparation and in vivo toxicity study of allantoin incorporated hyaluronic acid-L-cysteine oral solution: A future treatment for mucositis

Background: Thiolated hyaluronic acid (HA) with interesting properties, such as muco-adhesiveness, enzyme inhibitory, permeation enhancing, and release controlling properties can be applied for drug delivery in various diseases like mucositis. The purpose of this study was to evaluate the stability and toxicity of thiol modified HA by the aid of L-cysteine ethyl ester hydrochloride (Cys) named (HA-Cys) and allantoin (Alla) incorporated HA-Cys (HA-Cys-Alla) to reveal their potential for the future treatment of mucositis. Methods: The HA modification and drug incorporation were investigated using FTIR spectroscopy. The evaluation of in vitro cytotoxicity on Caco-2 cell line by means of MTT assay and in vivo toxicity by measuring the hematological and biochemical parameters in rats were performed. The appearance stability of HA-Cys and HA-Cys-Alla was evaluated at room and refrigerator temperatures over time. In addition, the stability of HA-Cys and HA-Cys-Alla subjected to heating and cooling, freeze-thaw, centrifugal forces, as well as the pH stability under the above-mentioned conditions were also investigated. Results: The results indicated that the synthesized HA-Cys and HA-Cys-Alla with pseudo-plastic rheological behavior demonstrated excellent stability at refrigerator temperature. Although HA-Cys showed good stability, the HA-Cys-Alla revealed color change at room temperature. Moreover, despite no much resistance of HA-Cys and HA-Cys-Alla against the heating-cooling test, the samples exhibited good resistance against freeze-thaw and centrifugal forces. Also, convenient pH stability and high in vitro and in vivo biocompatibility were observed. Conclusions: The low in vitro and in vivo toxicity and convenient stability of HA-Cys-Alla has introduced it as a proper candidate for future clinical applications.

Phytochemical composition, antifungal activity, in vitro and in vivo toxicity of Syzygium cumini (L.) Skeels leaves extract

This study determined phytochemical composition, antifungal activity and toxicity in vitro and in vivo of Syzygium cumini leaves extract (Sc). Thus, was characterized by gas chromatography coupled to mass spectrometry and submitted to determination of Minimum Inhibitory (MIC) and Fungicidal concentrations (MFC) on reference and clinical strains of Candida spp. and by growth kinetics assays. Toxicity was verified using in vitro assays of hemolysis, osmotic fragility, oxidant and antioxidant activity in human erythrocytes and by in vivo acute systemic toxicity in Galleria mellonella larvae. Fourteen different compounds were identified in Sc, which showed antifungal activity (MIC between 31.25-125 μg/mL) with fungistatic effect on Candida. At antifungal concentrations, it demonstrated low cytotoxicity, antioxidant activity and neglible in vivo toxicity. Thus, Sc demonstrated a promising antifungal potential, with low toxicity, indicating that this extract can be a safe and effective alternative antifungal agent.