Design and synthesis of novel glycyrrhetin ureas as anti-inflammatory agents for the treatment of acute kidney injury

GC/MS and 2D NMR-based approach to evaluate the chemical profile of hydroalcoholic extract from Agaricus blazei Murill and its anti-inflammatory effect on human neutrophils

ETHNOPHARMACOLOGICAL RELEVANCE

Agaricus blazei Murill (AbM) is one of the main mushrooms used for medicinal purposes. The use of AbM in the preparation of teas is widespread mainly in Asian countries, while in Brazil it is used as a functional food to combat inflammatory diseases and cancer.

AIM OF THE STUDY

The main focus of this study was the characterization of the chemical profile of the hydroalcoholic extract of Agaricus blazei Murill (AbE), as well as the evaluation of its cytotoxic and anti-inflammatory potential using human neutrophils.

MATERIALS AND METHODS

The extract was prepared by dynamic maceration using a mixture of ethanol and water (70/30, v v-1) as solvent. The chemical profile characterization was carried out by 2D NMR and GC-MS techniques. The cytotoxicity of AbE was evaluated through studies of hemolytic potential, cell viability and membrane integrity. The anti-inflammatory activity was analyzed by a PMA-induced neutrophil degranulation assay.

RESULTS

Chemical analysis of AbE revealed the presence of 28 metabolites in its composition, with mannitol as the major compound. AbE at 1-200 μg mL-1 and mannitol at 4-160 μg mL-1, showed low hemolytic and cytotoxic potential against human red blood cells and neutrophils. Furthermore, both were able to significantly reduce the release of myeloperoxidase.

CONCLUSIONS

These results indicate that AbE is a promising natural product to be incorporated into pharmaceutical dosage forms intended for the adjuvant treatment of inflammatory diseases.

A review of typical biological activities of glycyrrhetinic acid and its derivatives

Glycyrrhetinic acid, a triterpenoid compound primarily sourced from licorice root, exhibits noteworthy biological attributes, including anti-inflammatory, anti-tumor, antibacterial, antiviral, and antioxidant effects. Despite these commendable effects, its further advancement and application, especially in clinical use, have been hindered by its limited druggability, including challenges such as low solubility and bioavailability. To enhance its biological activity and pharmaceutical efficacy, numerous research studies focus on the structural modification, associated biological activity data, and underlying mechanisms of glycyrrhetinic acid and its derivatives. This review endeavors to systematically compile and organize glycyrrhetinic acid derivatives that have demonstrated outstanding biological activities over the preceding decade, delineating their molecular structures, biological effects, underlying mechanisms, and future prospects for assisting researchers in finding and designing novel glycyrrhetinic acid derivatives, foster the exploration of structure-activity relationships, and aid in the screening of potential candidate compounds.

Fusion of Michael-acceptors enhances the anti-inflammatory activity of ginsenosides as potential modulators of the NLRP3 signaling pathway

Ginsenosides are a promising group of secondary metabolites for developing anti-inflammatory agents. In this study, Michael acceptor was fused into the aglycone A-ring of protopanoxadiol (PPD)-type ginsenosides (MAAG), the main pharmacophore of ginseng, and its liver metabolites to produce novel derivatives and assess their anti-inflammatory activity in vitro. The structure-activity relationship of MAAG derivatives was assessed based on their NO-inhibition activities. Of these, a 4-nitrobenzylidene derivative of PPD (2a) was the most effective and dose-dependently inhibited the release of proinflammatory cytokines. Further studies indicated that 2a-induced downregulation on lipopolysaccharide (LPS)-induced iNOS protein expression and cytokine release may be related to its inhibitory effect on MAPK and NF-κB signaling pathways. Importantly, 2a almost completely inhibited LPS-induced production of mitochondrial reactive oxygen species (mtROS) and LPS-induced NLRP3 upregulation. This inhibition was higher than that by hydrocortisone sodium succinate, a glucocorticoid drug. Overall, the fusion of Michael acceptors into the aglycone of ginsenosides greatly enhanced the anti-inflammatory activities of the derivatives, and 2a alleviated inflammation considerably. These findings could be attributed to the inhibition of LPS-induced mtROS to block abnormal activation of the NLRP3 pathway.

Novel benzothiazole‒urea hybrids: Design, synthesis and biological activity as potent anti-bacterial agents against MRSA

Novel benzothiazole‒urea hybrids were designed, synthesized and evaluated their anti-bacterial activity. They only exhibited anti-bacterial activity against Gram-positive bacteria, including clinical methicillin-resistant S. aureus (MRSA), compounds 5f, 5i, 8e, 8k and 8l exhibited potent activity (MIC = 0.39 and 0.39/0.78 μM against SA and MRSA, respectively). Crystal violet assay showed that compounds 5f, 8e and 8l not only inhibited the formation of biofilms but also eradicated preformed biofilms. Compound 8l had membrane disruption, little propensity to induce resistance, benign safety and in vivo anti-MRSA efficacy in a mouse model of abdominal infection. Therefore, our data demonstrated the potential to advance benzothiazole‒urea hybrids as a new class of antibiotics.

Elaboration of novel urea bearing schiff bases as potent in vitro anticancer candidates with low in vivo acute oral toxicity

A novel series of urea Schiff base derivatives were synthesized via the condensation of o-phenylenediamine, naphthyl isocyanate and appropriate aryl aldehyde. The results of the in vitro cytotoxic activities of compounds 5a–h against cancer cells lines PC3, SKOV-3 and HeLa, revealed that almost all compounds exhibited good to moderate activities Compound 5g owing bromine atom at p-position displayed higher activity compared to homolog 5b possessing chlorine atom due to adequate diameter of bromine which is more favourable than chlorine for the inhibition activity. In addition, compound 5h is the best candidate of this series exhibiting excellent activity for three cancer cells lines. Compound 5h demonstrated also an excellent activity with IC50 value of 0.6±0.3μg/mL for prostate cancer cell line PC3 and it is considered more effective than the standard drug doxorubicin Dox (IC50 = 2.6±0.03μg/mL). The most active compound 5h displayed the best activity against ovarian cancer cell line SKOV3 with IC50 = 1.8±0.2μg/mL. This results are higher than clinically used drug Dox (IC50. 2.2±0.02μg/mL). The results of screening activities cytotoxic effect toward cervix cancer cell line HeLa, affirm that compound 5h manifest an activity with IC50 value of 2.2±0.4μg/mL comparable to Dox (IC50. 1.9±0.04μg/mL). In the current study, in vivo acute oral toxicity assessment of urea Schiff base hybrid compounds 5a – h indicated that there was no mortality on treated female mice during 14 days assessment test compared with the vehicle-treated group confirming the safety with LD50 greater than 2000 mg/kg. In the actual study, the results affirmed that compounds 5a–h manifested in vivo no toxicity to saint cells, the compounds 5b, 5g and 5h presented higher anticancer activities against three cancer cells which authorizes promoters to use them as candidate anticancer agents.

Renal Nano-drug delivery for acute kidney Injury: Current status and future perspectives

Acute kidney injury (AKI) causes considerable morbidity and mortality, particularly in the case of post-cardiac infarction or kidney transplantation; however, the site-specific accumulation of small molecule reno-protective agents for AKI has often proved ineffective due to dynamic fluid and solute excretion and non-selectivity, which impedes therapeutic efficacy. This article reviews the current status and future trajectories of renal nanomedicine research for AKI management from pharmacological and clinical perspectives, with a particular focus on appraising nanosized drug carrier (NDC) use for the delivery of reno-protective agents of different pharmacological classes and the effectiveness of NDCs in improving renal tissue targeting selectivity and efficacy of said agents. This review reveals the critical shift in the role of the small molecule reno-protective agents in AKI pharmacotherapy - from prophylaxis to treatment - when using NDCs for delivery to the kidney. We also highlight the need to identify the accumulation sites of NDCs carrying reno-protective agents in renal tissues during in vivo assessments and detail the less-explored pharmacological classes of reno-protective agents whose efficacies may be improved via NDC-based delivery. We conclude the paper by outlining the challenges and future perspectives of NDC-based reno-protective agent delivery for better clinical management of AKI.