Changes in Expression and Function of Placental and Intestinal P-gp and BCRP Transporters during Pregnancy

Differential absorption and metabolic characteristics of organic acid components in pudilan xiaoyan oral liquid between young rats and adult rats

ETHNOPHARMACOLOGICAL RELEVANCE

Pudilan Xiaoyan Oral Liquid (PDL) is a proprietary Chinese medicinal preparation approved by the State for treating acute pharyngitis in both adults and children (Approval No. Z20030095). It is worth noting that children exhibit unique physiopathological characteristics compared to adults. However, the in vivo regulatory characteristics of PDL in treating acute pharyngitis in children remain incompletely understood.

AIM OF THE STUDY

The differential absorption and metabolism characteristics of the main pharmacological components in PDL in young and adult rats were investigated with a view to providing a reference for preclinical data of PDL in medication for children.

MATERIALS AND METHODS

This study utilized UPLC-Q-TOF-MS to investigate the pharmacodynamic material basis of PDL. The focus was on the gastrointestinal digestion and absorption characteristics of organic acid components in PDL (PDL-OAC), known as the primary pharmacodynamic components in this formulation. The research combined in vitro dynamic simulation and a Quadruple single-pass intestinal perfusion model to examine these characteristics. The permeability properties of PDL-OAC were evaluated using an artificial parallel membrane model. Additionally, an acute pharyngitis model was established to evaluate the histopathological condition of the pharynx in young rats using H&E staining. The levels of IL-1β, TNF-α, IL-6, and IL-10 in blood and pharyngeal tissue homogenates of young rats were quantified using ELISA kits.

RESULTS

A total of 91 components were identified in PDL, including 33 organic acids, 24 flavonoids, 14 alkaloids, 5 terpenoids and coumarins, 3 sugars, and 12 amino acids. The PDL-OAC exhibited a significant reduction in IL-1β, TNF-α, IL-6, and IL-10 levels in the pharyngeal tissues of young rats with acute pharyngitis. Results from dynamic simulation studies of gastrointestinal fluids revealed that the PDL-OAC (Specifically chlorogenic acid (CGA), gallic acid (GA), chicoric acid (CRA), and caffeic acid (CA)) were effectively stabilized in the gastrointestinal fluids of both children and adults in vitro. Young rats, characterized by thinner intestinal walls and higher permeability, efficiently absorbed the four organic acids across the entire intestinal segment. The absorption of CGA, GA, and CRA followed a concentration-dependent pattern, with CGA and GA absorption being influenced by exocytosis.

CONCLUSION

The efficacy of the PDL-OAC in treating acute pharyngitis was demonstrated in young rats. The absorption rate of these components was observed to be faster in young rats compared to adult rats, underscoring the need for dedicated studies on the drug's usage in children. This research provides valuable insights for the appropriate clinical use of PDL in pediatric patients.

Novel betulin derivatives as multidrug reversal agents targeting P-glycoprotein

Chemotherapy is a powerful means of cancer treatment but its efficacy is compromised by the emergence of multidrug resistance (MDR), mainly linked to the efflux transporter ABCB1/P-glycoprotein (P-gp). Based on the chemical structure of betulin, identified in our previous work as an effective modulator of the P-gp function, a series of analogs were designed, synthesized and evaluated as a source of novel inhibitors. Compounds 6g and 6i inhibited rhodamine 123 efflux in the P-gp overexpressed leukemia cells, K562/Dox, at concentrations of 0.19 µM and 0.39 µM, respectively, and increased the intracellular accumulation of doxorubicin at the submicromolar concentration of 0.098 µM. Compounds 6g and 6i were able to restore the sensitivity of K562/Dox to Dox at 0.024 µM and 0.19 µM, respectively. Structure-activity relationship analysis and molecular modeling revealed important information about the structural features conferring activity. All the active compounds fitted in a specific region involving mainly transmembrane helices (TMH) 4-6 from one homologous half and TMH 7 and 12 from the other, also showing close contacts with TMH 6 and 12. Compounds that bound preferentially to another region were inactive, regardless of their free energy of binding. It should be noted that compounds 6g and 6i were devoid of toxic effects against peripheral blood mononuclear normal cells and erythrocytes. The data obtained indicates that both compounds might be proposed as scaffolds for obtaining promising P-gp inhibitors for overcoming MDR.

Glucocorticoids and intrauterine programming of nonalcoholic fatty liver disease

Accumulating epidemiological and experimental evidence indicates that nonalcoholic fatty liver disease (NAFLD) has an intrauterine origin. Fetuses exposed to adverse prenatal environments (e.g., maternal malnutrition and xenobiotic exposure) are more susceptible to developing NAFLD after birth. Glucocorticoids are crucial triggers of the developmental programming of fetal-origin diseases. Adverse intrauterine environments often lead to fetal overexposure to maternally derived glucocorticoids, which can program fetal hepatic lipid metabolism through epigenetic modifications. Adverse intrauterine environments program the offspring's glucocorticoid-insulin-like growth factor 1 (GC-IGF1) axis, which contributes to postnatal catch-up growth and disturbs glucose and lipid metabolism. These glucocorticoid-driven programming alterations increase susceptibility to NAFLD in the offspring. Notably, after delivery, offspring often face an environment distinct from their in utero life. The mismatch between the intrauterine and postnatal environments can serve as a postnatal hit that further disturbs the programmed endocrine axes, accelerating the onset of NAFLD. In this review, we summarize the current epidemiological and experimental evidence demonstrating that NAFLD has an intrauterine origin and discuss the underlying intrauterine programming mechanisms, focusing on the role of overexposure to maternally derived glucocorticoids. We also briefly discuss potential early life interventions that may be beneficial against fetal-originated NAFLD.