Nephrotoxicity induced by natural compounds from herbal medicines - a challenge for clinical application

Dose-related effects of eugenol: Exploring renal functionality and morphology in healthy Wistar rats

Eugenol has pharmacological properties, but its impact on renal function is limitedly studied. Thus, this study evaluated the effects of eugenol at 10, 20, and 40 mg kg-1, administered via gavage for 60 days, on histological, biochemical, oxidative, and proteomic parameters in rat kidneys. Adult Wistar rats treated with 10 mg kg-1 of eugenol had kidneys with low total antioxidant capacity, high nitric oxide content, and high percentual of blood vessels, with no damage to renal function or morphology. The kidney proteome revealed an upregulation of proteins associated with energy metabolism, oxidative stress, and mitochondrial function. Eugenol at 20 mg kg-1 did not alter kidney histology but inhibited Na+/K+ ATPase activity. This dose elicited an upregulation of proteins associated with mitochondrial function and cellular defense. Finally, 40 mg kg-1 eugenol had more pronounced effects on the kidney, increasing serum sodium, potassium, and chloride levels, inhibiting Na+/K+ ATPase activity, triggering an adaptive response to oxidative stress, and showing apical brush border thinness in proximal tubules. We concluded that eugenol exerted dose-dependent effects on kidney function and morphology. These findings highlight the importance of careful consideration of eugenol's dosage in therapeutic applications.

Unraveling the metabolomic profile and acute toxicity of ethanolic extract from Mimosa tenuiflora (Willd.) Poir. root bark

Mimosa tenuiflora (Fabaceae) is popularly known in Brazil as "Jurema preta". From the bark of its root, "jurema wine" is obtained, a psychedelic drink used in Indigenous religious rituals in Northeastern Brazil. This work aimed to investigate the chemical composition and acute oral toxicity of the ethanolic extract of the root bark from M. tenuiflora (EEMt). EEMt was analyzed by UPLC-QToF-MS/MS and DI-ESI-IT-MSn. Oral administration of EEMt was performed once at doses of 300 and 2000 mg/kg in female Swiss mice. Signs and symptoms of intoxication, as well as mortality were monitored for 14 days. Thirteen compounds were annotated in EEMt: eight type B proanthocyanidins, three alkaloids, a glycosylated flavonol, and a dihydrochalcone derivative. The acute administration of 300 and 2000 mg/kg of EEMt did not show mortality. It also did not change the food intake or body weight of the animals. However, the relative weights of the kidneys were significantly changed for both doses. Changes in hematological and biochemical parameters were found. In addition, histopathological changes were also observed in the heart, liver, and kidneys. Thus, based on our findings, EEMt presented an LD50 greater than 2000 mg/kg and was therefore classified in category 5 of the Globally Harmonized Classification System (GHS). EEMt showed acute oral toxicity by altering hematological, biochemical and histological parameters.

Comprehensive HRMS Screening and Risk Assessments of Aristolochic Acid Analogues in Asari Radix et Rhizoma and Related Commercial Health Products

Aristolochic acid analogues (AAAs) are well-known toxins. We performed the first comprehensive screening on AAAs in Asari Radix et Rhizoma (underground part of Asarum heterotropoides Schmidt), the only Aristolochiaceae plant widely used in clinical practice. LC-HRMS revealed 70 trace AAAs using polygonal mass defect filtering and precursor ion list strategies, 38 of which were newly discovered in A. heterotropoides. UHPLC-QTrap-MS/MS was then utilized for quantitative/semiquantitative analysis of 26 abundant compounds. Seventeen AAAs were detected from 91 batches of A. heterotropoides and 20 AAAs from 166 consumable products. For 141 Asari-containing proprietary products, aristolactam I and aristolactam II-glucoside exhibited the widest distribution, present in 98% products. AA IVa was the most abundant, detected in 91%. Notably, 60% of the products contained AA I (0.03-0.79 ppm). The safety was assessed using linear extrapolation, permitted daily exposure, cumulative amount, and the margin of exposure. It is recommended that AA I content be limited to 3 ppm.

Rational design of a ratiometric fluorescent aptasensor for patulin in traditional Chinese medicine through the studies of the interaction mechanism between its DNA aptamer and the target molecule

Patulin (PAT) is a kind of mycotoxin which must be monitored for the sake of quality and safety in traditional Chinese medicine (TCM) owing to its harm to human health. On this account, a rationally designed ratiometric fluorescent aptasensor was developed based on the studies of the interaction mechanism between PAT and its aptamer (PAT-APT). First, CD spectroscopy, molecular docking, and molecular dynamic simulation were applied to investigate the details on how PAT-APT binds with its target molecule. The results indicated that the structure of PAT-APT changed to a certain extent and was stabilized after binding with PAT. C-11, C-37 and C-38 were the key sites for the recognition and interaction between PAT-APT and its target. Second, based on these results, a ratiometric aptasensor was designed using fluorescence resonance energy transfer (FRET) and synchronous fluorescence spectroscopy. A complementary sequence (cDNA) to the aptamer with an appropriate length and hybridization position was obtained through rational design and optimization. Both PAT-APT and cDNA were labeled using a pair of fluorophores, which could generate FRET when the two single-stranded oligonucleotides hybridized. The accurate detection of PAT could be realized according to the change ratio of the fluorescence intensity at the corresponding wavelengths of the two fluorophores before and after the assay. The aptasensor achieved an ultralow limit of detection of 0.16 nM, perfect selectivity, and satisfactory practicability in complex TCM samples. To our knowledge, this is the first aptasensor for PAT designed through the interaction mechanism between its aptamer and the target molecule. Moreover, the assay for PAT is cost-effective, does not need complicated pretreatment and only takes less than an hour. In summary, this study makes a contribution to the safety control of TCM and provides a thinking mode from mechanism to rational design to conquer the problem of sensitive aptasensing of one component in a complex system.

Potential therapeutic effects of Chinese meteria medica in mitigating drug-induced acute kidney injury

Drug-induced acute kidney injury (DI-AKI) is one of the leading causes of kidney injury, is associated with high mortality and morbidity, and limits the clinical use of certain therapeutic or diagnostic agents, such as antineoplastic drugs, antibiotics, immunosuppressants, non-steroidal anti-inflammatory drugs, and contrast media. In recent years, numerous studies have shown that many Chinese meteria medica, metabolites derived from botanical drugs, and Chinese medicinal formulas confer protective effects against DI-AKI by targeting a variety of cellular or molecular mechanisms, such as oxidative stress, inflammatory, cell necrosis, apoptosis, and autophagy. This review summarizes the research status of common DI-AKI with Chinese meteria medica interventions, including cisplatin, gentamicin, contrast agents, methotrexate, and acetaminophen. At the same time, this review introduces the metabolites with application prospects represented by ginseng saponins, tetramethylpyrazine, panax notoginseng saponins, and curcumin. Overall, this review provides a reference for the development of promising nephroprotectants.