RESUMEN
Purpose: In China, herbal preparation is commonly administered transdermally for treating pediatric diarrhea. However, few studies have probed into their antidiarrheal mechanisms. This study was designed to investigate the antidiarrheal effect of Renzhu ointment (Renzhuqigao, RZQG) and its underlying mechanisms via transdermal administration. Methods: The main components of RZQG were confirmed by gas chromatography-mass spectrometry (GC-MS). The effect of RZQG on L-type voltage-dependent calcium channel (L-VDCC) was evaluated by CaCl2- and ACh-induced contraction in isolated colon. The antidiarrheal efficacy of RZQG was further investigated by the senna-induced diarrhea mice based on the frequency of loose stools, diarrhea rate and index, fecal moisture content, and the basal tension of the colon. Additionally, the protein expression of CACNA1C, CACNA1D, cAMP, and PKA were detected with Western blot and immunohistochemistry (IHC). Results: GC-MS analysis determined 14 components in RZQG. In vitro, RZQG relaxed the CaCl2- and ACh-induced tension, while nifedipine (a L-VDCC inhibitor) and H-89 (a PKA inhibitor) decreased the relaxation. In vivo, animal model showed that transdermal administration of RZQG exhibited a significant reduction in the frequency of loose stools, diarrhea rate and index, fecal moisture content and the basal tension. Compared to the model group, the colon of mice treated with RZQG showed lower expression of CACNA1C, CACNA1D, cAMP, and PKA. IHC results showed that cAMP was downregulated in colonic smooth muscle after RZQG treatment. Conclusion: RZQG improved diarrhea symptoms and down-regulated the expression of CACNA1C and CACNA1D via transdermal administration, which is closely associated with the cAMP/PKA signaling pathway in colonic smooth muscle.
Asunto(s)
Antidiarreicos , Canales de Calcio Tipo L , Animales , Ratones , Administración Cutánea , Antidiarreicos/farmacología , Cloruro de Calcio , Pomadas , Senósidos , Diarrea/inducido químicamente , Diarrea/tratamiento farmacológico , Fármacos Gastrointestinales , Modelos Animales de EnfermedadRESUMEN
Purpose: Renzhu ointment (Renzhuqigao, RZQG) is a patented herbal drug derived from Chinese traditional medicine formula and modern clinical experience for the transdermal treatment of non-infectious infantile diarrhoea. The safety of RZQG in preclinical studies has not been reported.Materials and methods: In this study, the pups of parent rats were examined for sub-chronic toxicity and developmental toxicity. After 21 days of birth, they were exposed to RZQG through their abdominal skin at doses of 0.1, 0.3, and 0.9 g/kg/day for 4 weeks and then were observed for another four weeks during their recovery period.Results: During the administration period, RZQG had no significant toxicological effect on body weight, food consumption, external eye examination, urinalysis, bone marrow examination, histopathology, central nervous system, reproductive system, or skeletal development. However, in the 0.9 g/kg/day group, the skin of some rats became dry and cracked, red and swollen, forming a white scab, while the white blood cells (WBC) count in female rats was lower and cholesterol (CHOL), triglycerides (TG), and glutamyl-transferase (GGT) were higher (p < 0.05).Conclusions: Rats receiving 0.9 g/kg/day exhibited skin irritation and were suspected to have a mild liver injury. There was no evidence of delayed toxicity four weeks after withdrawal. Therefore, the no-observed adverse effect level of RZQG was 0.3 g/kg/day (30 times the clinical dose planned and 4.92 times the human equivalent dose).
Asunto(s)
Medicina Tradicional China , Administración Cutánea , Animales , Femenino , Humanos , Nivel sin Efectos Adversos Observados , Pomadas/toxicidad , Ratas , Ratas Sprague-DawleyRESUMEN
A facile approach is proposed herein to fabricate YMn2O5 powders with the hydrothermal method with oxygen as an oxidant. The structure and morphology of the as-synthesized YMn2O5 powders were characterized by XRD, SEM, and high-resolution transmission electron microscopy (HRTEM). The results manifested that the main factors that affected the formation of the rod-like YMn2O5 structures were the stirring time, hydrothermal temperature, and hydrothermal time. The oxidation time in the air had a remarkable effect on the final product by oxidizing Mn2+ ions to Mn3+ ions and Mn4+ ions. The obtained YMn2O5 powder was single crystalline and possessed a nanorod morphology, where the growth direction was along the c axis. The possible formation mechanism involved a dissolution-crystallization mechanism. Under the 397 nm excitation, the Mn4+ ions exhibited an intense orange emission at 596 nm. The energy bandgap of YMn2O5 powders was 1.18 eV.