Development of an LC-DAD-MS-Based Method for the Analysis of Hydroxyanthracene Derivatives in Food Supplements and Plant Materials

Products based on plants containing hydroxyanthracene derivatives (HADs)-such as Rheum, Cassia, and Aloe species-are widely used in food supplements or nutraceuticals due to their laxative effects. A more restricted control of HAD contents in food supplements has been implemented by EU Regulation 2021/468, in order to increase the safety of these preparations. Due to their toxicity, aloin A, aloin B, aloe emodin, emodin, and the synthetic derivative danthron have been listed as prohibited substances in food supplements, being tolerated in amounts < 1 mg kg(-1) in marketed products. In this work, we report the development of a sensitive and fast LC-DAD-MS-based procedure for the determination of these five compounds in food supplements and plant materials or extracts. The entire procedure includes a simple sample preparation step, where target analytes are concentrated by means of solvent extraction and evaporative concentration (solid samples), or by lyophilisation (liquid samples). The average LOQ of 0.10 mg/L, LOD of 0.03 mg/L, accuracy, and precision with CVs below 12.72 were obtained for the studied analytes. This method is suitable for assessing the compliance of commercial products and raw materials with EU Regulation 2021/468. Furthermore, the proposed method can represent a starting point for the development of a unique and standardised analytical approach for the determination of other HADs under the attention of EU authorities

3D human foreskin model for testing topical formulations of sildenafil citrate

: Sildenafil citrate is an approved drug used for the treatment of erectile dysfunction and premature ejaculation. Despite a widespread application, sildenafil citrate shows numerous adverse cardiovascular effects in high-risk patients. Local transdermal drug delivery of this drug is therefore being explored as an interesting and noninvasive alternative administration method that avoids adverse effects arised from peak plasma drug concentrations. Although human and animal skin represents the most reliable models to perform penetration studies, they involve a series of ethical issues and restrictions. For these reasons new in vitro approaches based on artificially reconstructed human skin or "human skin equivalents" are being developed as possible alternatives for transdermal testing. There is little information, however, on the efficiency of such new in vitro methods on cutaneous penetration of active ingredients. The objective of the current study was to investigate the sildenafil citrate loaded in three commercial transdermal vehicles using 3D full-thickness skin equivalent and compare the results with the permeability experiments using porcine skin. Our results demonstrated that, while the formulation plays an imperative role in an appropriate dermal uptake of sildenafil citrate, the D coefficient results obtained by using the 3D skin equivalent are comparable to those obtained by using the porcine skin when a simple drug suspension is applied (1.17 × 10-10 ± 0.92 × 10-10 cm2/s vs 3.5 × 102 ± 3.3 × 102 cm2/s), suggesting that in such case, this 3D skin model can be a valid alternative for ex-vivo skin absorption experiments

Loss of CDKN1B induces an age‐related clonal hematopoietic disorder via Notch2 activity dysregulation

No abstract availabl

Melatonin MT1 receptors as a target for the psychopharmacology of bipolar disorder: a translational study

The treatment of bipolar disorder (BD) still remains a challenge. Melatonin (MLT), acting through its two receptors MT1 and MT2, plays a key role in regulating circadian rhythms which are dysfunctional in BD. Using a translational approach, we examined the implication and potential of MT1 receptors in the pathophysiology and psychopharmacology of BD. We employed a murine model of the manic phase of BD (Clock mutant (ClockΔ19) mice) to study the activation of MT1 receptors by UCM871, a selective partial agonist, in behavioral pharmacology tests and in-vivo electrophysiology. We then performed a high-resolution Nuclear Magnetic Resonance study on isolated membranes to characterize the molecular mechanism of interaction of UCM871. Finally, in a cohort of BD patients, we investigated the link between clinical measures of BD and genetic variants located in the MT1 receptor and CLOCK genes. We demonstrated that: 1) UCM871 can revert behavioral and electrophysiological abnormalities of ClockΔ19 mice; 2) UCM871 promotes the activation state of MT1 receptors; 3) there is a significant association between the number of severe manic episodes and MLT levels, depending on the genetic configuration of the MT1 rs2165666 variant. Overall, this work lends support to the potentiality of MT1 receptors as target for the treatment of BD

Biochemical and cellular mechanism of protein kinase CK2 inhibition by deceptive curcumin

Protein kinase CK2 is an antiapoptotic cancer-sustaining protein. Cur-cumin, reported previously as a CK2 inhibitor, is too bulky to be accom-modated in the CK2 active site and rapidly degrades in solution generatingvarious ATP-mimetic inhibitors; with a detailed comparative analysis, bymeans of both protein crystallography and enzymatic inhibition, ferulicacid was identified as the principal curcumin degradation product responsi-ble for CK2 inhibition. The other curcumin derivatives vanillin, feruloyl-methane and coniferyl aldehyde are weaker CK2 inhibitors. The highinstability of curcumin in standard buffered solutions flags this compound,which is included in many commercial libraries, as a possible source of mis-leading interpretations, as was the case for CK2. Ferulic acid does notshow any cytotoxicity and any inhibition of cellular CK2, due to its poorcellular permeability. However, curcumin acts as a prodrug in the cellularcontext, by generating its degradation products inside the treated cells, thusrescuing CK2 inhibition and consequently inducing cell death. Through theintracellular release of its degradation products, curcumin is expected toaffect various target families; here, we identify the first bromodomain ofBRD4 as a new target for those compounds

Bergamot (Citrus bergamia) peel extract as new hypocholesterolemic agent modulating PCSK9 expression

Citrus bergamia extracts have been studied for the management of hypercholesterolemia disorders. Up to now limited information is available concerning the activity of its main phytoconstituents towards the main targets of the cholesterol homeostasis. In the present study, the effects of bergamot peel extract and isolated constituents, namely glycosidic and non-glycosidic flavonoids, one coumarin and one limonoid on the low-density lipoprotein receptor (LDLR) and proprotein convertase subtilisin/kexin type 9 (PCSK9) were evaluated by using cultured HuH7 cell line. Furthermore, for the first time the effects of bergamot peel extract were studied to describe a potential hypolipidemic action. Significant differences were observed due to glycosylation and different substitution on flavanone moiety (O-methylation). Considering the thirteen isolated compounds, both naringenin-7-O-rutinoside (NA-rut) and apigenin-6,8-C-glicoside induced the expression of the LDLR while no effect was observed on PCSK9. However, hesperetin (HE) and its derivatives, hesperetin-7-O-glucoside and hesperetin-7-O-neohesperidoside (HE-glu, HE-neo) and eriodictyol (ER) showed a statin-like effect since a significant increase of both LDLR and PCSK9 expression were detected. Furthermore, bergamot peel extract (BE) firstly demonstrated a significant reduction of PCSK9 expression, indicating a potential adjuvant action to statins. BE, HE-neo, and NA-rut reduced intracellular sterols and the expression of PCSK9 transcription factor HNF1-α. BE also significantly improved the LDL uptake u Huh7 cells. Based on the present data, bergamot peel constituents can play a role in the management of hypercholesterolemia, on one hand they may produce an adjuvant action in combination with statins, while on the other hand they may have a statin-like effect. Additionally, BE may be a good candidate as an adjuvant to statins action