Preparation and evaluation of a coated smectite clay-based material modified with epichlorohydrin-dimethylamine for the diclofenac removal

Efficient adsorptive removal of used drugs during the COVID-19 pandemic from contaminated water by magnetic graphene oxide/MIL-88 metal-organic framework/alginate hydrogel beads

Currently, the presence of drugs used in the COVID-19 pandemic in water bodies is worrisome due to their high toxicity, which necessitates their critical removal by developing highly efficient adsorbents. Hence, in this study, alginate hydrogel beads of magnetic graphene oxide@MIL-88 metal-organic framework (GO@Fe3O4@MIL-88@Alg) were prepared for the first time and then utilized as a new absorption system for the removal of COVID-19 drugs such as doxycycline (DOX), hydroxychloroquine (HCQ), naproxen (NAP), and dipyrone (DIP) from aqueous solutions by batch adsorption manner. The effects of different experimental factors, such as adsorbent dosage, contact time, pH, drug concentration, temperature, ionic strength, presence of an external magnetic field (EMF), and magnet distance from the adsorption flask were optimized for the removal of COVID-19 drugs. The adsorption equilibrium isotherm proved that the adsorption process of DOX, HCQ, NAP, and DIP drugs on GO@Fe3O4@MIL-88@Alg hydrogel beads conformed to the Langmuir model and followed the pseudo-second-order adsorption kinetics. The maximum adsorption capacities of DOX, HCQ, NAP, and DIP drugs obtained for GO@Fe3O4@MIL-88@Alg hydrogel beads with the Langmuir model were 131.57, 79.92, 55.55, and 49.26 mg/g at 298 K, respectively. The thermodynamic study suggested a spontaneous endothermic adsorption process. Also, the conclusion from this study confirmed the validity of GO@Fe3O4@MIL-88@Alg hydrogel beads for excellent removal of COVID-19 drugs from water samples. It was also found that the GO@Fe3O4@MIL-88@Alg hydrogel beads could be reused with satisfactory removal efficiency in six cycles. Based on the study, the GO@Fe3O4@MIL-88@Alg hydrogel beads could be considered a sustainable, simple, economical, environmentally friendly absorption system for the removal of pharmaceutical contaminants from water.

Jian-Pi-Yin decoction attenuates lactose-induced chronic diarrhea in rats by regulating GLP-1 and reducing NHE3 ubiquitination and phosphorylation

Objectives

Jian-Pi-Yin decoction (JPY), a prescription derived from the traditional Chinese medicine Shen-Ling-Bai-Zhu-San, has shown good clinical efficacy in the treatment of diarrhea caused by lactose intolerance. However, the mechanism of action of JPY in the treatment of diarrhea is not fully understood.

Design

In this study, a rat diarrhea model was induced by high lactose feeding combined with standing on a small platform to investigate the ameliorating effect of JPY on hyper lactose-induced diarrhea in rats and its possible mechanism.

Methods

The rat model of hyper lactose diarrhea was given high, medium, and low doses of JPY and the positive control drug Smida by gavage for 1 week. At the same time, NA+-H+ exchanger 3 (NHE3) inhibitor Tenapanor was administered orally for 3 weeks. Body weight, food intake, water intake, grip strength, and severity of diarrhea symptoms were measured in rats throughout the study. The serum, colon, and jejunum tissues of the model and drug-treated rats were collected for histopathological examination and analysis of relevant indicators.

Results

JPY significantly alleviated the symptoms of fatigue, diet reduction and diarrhea in the model group. Glucagon-like peptide-1 (GLP-1) and cyclic adenosine monophosphate (cAMP) expression were also down-regulated after JPY treatment. JPY can significantly promote NHE3 in intestinal tissues of rats with diarrhea, and the mechanism is related to the decrease of GLP-1, inhibition of cAMP/PKA pathway activation, an increase of ubiquitin-specific protease 7 (USP7) and USP10 expression, and decrease of NHE3 ubiquitination and phosphorylation.

Conclusion

JPY can reduce the expression of GLP-1, reduce the ubiquitination and phosphorylation of NHE3, regulate the expression of NHE3, at least partly improve ion transport in the intestinal epithelium, and improve the imbalance of electrolyte absorption, thus significantly reducing the diarrhea symptoms of rats with high lactose combined with small platform standing.

Innovation

In this study, we explored the mechanism of intestinal GLP-1 activation of cAMP/PKA signaling pathway from multiple dimensions, and increased its expression by reducing phosphorylation and ubiquitination of NHE3, thereby treating chronic diarrhea associated with lactose intolerance.