Toxicological evaluation of ergocalciferol, cholecalciferol, and their metabolites by a category approach

Vitamin D supplementation: Biochemical and inflammatory effects in non-pathological Wistar rats

Vitamin D3 (VD3) is shown to be a biochemical and physiological modulator of the body. Debates about route of administration, prescribed dosage and serum levels have arisen, and thus the interaction of VD3 with the body in overdose. Using an experimental model of Wistar rats of both sexes, rats were subdivided into 5 groups, which represents a control group, and 4 groups with VD3 treatments (2.500, 7.000, 14.000 and 21.000 IU/kg/week) for one month. Thereafter biochemical, hormonal, inflammatory and histological analyses were performed. Regarding the biochemical findings, there was an increase in the levels of the AST in comparison of the control group with the treatments with higher doses (14.000 IU and 21.000 IU). Furthermore, changes in the inflammatory cytokine profile were identified at doses of 14,000 IU and 21,000 IU, with an increase in inflammatory cytokines (IL-1β, IL-6, IL-8 and TNF-α) and a decrease in the anti-inflammatory IL-10. Histological evaluation of the liver tissue also revealed changes at the highest doses. Finally, in the evaluation of a murine physiological model, it showed that the supplementation of VD3 in overdoses there was an inflammatory exacerbation in the body, suggesting that the VD3 supplementation should be administered with caution, and takes into account physiological factors of the individual.

In silico and in vitro evaluation of the potential genotoxic impurities of vildagliptin

Establishing the safety of impurities in drug substances or products is crucial. The assessment of genotoxicity for these impurities and determining the acceptable limits pose considerable challenges, as recognized in recent guidelines. While the genotoxicity profile of vildagliptin-an oral hypoglycemic drug-is well established, there is limited knowledge about the genotoxic potential of its impurities. In this study, vildagliptin cyclic amidine, vildagliptin diketopiperazine, and vildagliptin amide were assessed in silico and in vitro for mutagenic and clastogenic/aneugenic potential using Ames and micronucleus tests. None of the investigated impurities showed mutagenic or clastogenic potential, thus, are considered non-mutagenic and non-clastogenic/aneugenic in vitro. These findings are consistent with negative in silico predictions for mutagenicity and clastogenicity/aneugenicity in vitro, indicating a good correlation between in silico and in vitro data. In conclusion, this study provides valuable information for the safety assessment of vildagliptin, confirming that its impurities are neither clastogenic/aneugenic nor mutagenic.

Filling data gap for nicotinic acid, nicotinate esters and nicotinamide for the determination of permitted daily exposure by a category approach

This study aimed to obtain necessary toxicological data using experimental and computational methods for the calculation of a common permitted daily exposure (PDE) which can be relevant for nicotinic acid and its esters and nicotinamide according to European Medicines Agency Guideline on setting health-based exposure limits. PDE calculation is mainly based on critical toxicological endpoints. During this procedure, critical toxicological endpoints data of an active pharmaceutical ingredient (API) may not be able to find satisfactorily. Hence, using toxicological data for another API that has a similar chemical structure can be a useful way. In this study, toxicological endpoints of nicotinic acid and its esters and nicotinamide were evaluated. Then, the data gaps in the toxicological endpoints were filledusing the read-across approach. Based on the current existing data, nicotinic acid and its esters and also nicotinamide are not genotoxic and do not have skin sensitization potential. These compounds do not present a concern for carcinogenicity and developmental/reproductive toxicity. Based on these critical endpoints and available experimental data, the final PDE of 10 mg/day was calculated for all category members. Our study showed the utility of the read-across for PDE calculation of APIs with experimental toxicological data gap.