Pharmacokinetics and tissue distribution of hydrazinocurcumin in rats

BACKGROUND

Curcumin, a natural polyphenol from Curcuma longa, is known to possess diversified pharmacological roles including anti-inflammatory, antioxidant, antiproliferative and antiangiogenic properties; however, its bioavailability is severely limited due to its poor solubility, poor absorption, rapid metabolism, and significant elimination. Hydrazinocurcumin (HZC), a novel analogue of curcumin has been reported to overcome the limitations of curcumin and also possesses multiple pharmacological activities. The present study aimed to evaluate the unexplored pharmacokinetic profile of this agent in experimental rats.

METHODS

Drug formulations were administered to the experimental animals via oral, intravenous and intraperitoneal routes. Blood samples were collected at different pre-determined time intervals to determine the pharmacokinetic parameters. To understand the biodistribution profile of HCZ, tissue samples were isolated from different groups of Sprague-Dawley rats at different time points. The pharmacokinetic parameters of HZC were evaluated after administration through oral (100 mg/kg), intraperitoneal (100 mg/kg) and intravenous (10 mg/kg) routes.

RESULTS

Significantly (p < 0.05) higher total AUC along with maximum concentration were evident with intraperitoneal administration when compared to the results of oral administration at a similar dose. In addition, shorter time to peak was observed with intraperitoneal administration. These results revealed a faster rate and longer duration of absorption with intraperitoneal administration, which further resulted in enhanced absolute bioavailability of HZC (29.17%) when compared to 5.1% upon oral dosing. The obtained data from the pharmacokinetic study indicated that HZC was instantaneously distributed and moderately eliminated from body fluids.

CONCLUSION

Based on the findings, it could be concluded that absorption of HZC is much higher via intraperitoneal route of administration compared to the oral administration.

Development and validation of bioanalytical method for the determination of hydrazinocurcumin in rat plasma and organs by HPLC-UV

Hydrazinocurcumin is a semi-synthetic analogue of curcumin with superior anticancer and anti-angiogenic activities. In the present work a simple and sensitive reverse phase high performance liquid chromatography (RP-HPLC) method for quantitative evaluation of hydrazinocurcumin in plasma and various organs of rats including liver, kidneys, brain, heart, lungs and spleen was developed. Hydrazinocurcumin was separated using octadecylsilane (Inertsil-ODS-3V) column in an isocratic mode using mobile phase consisting of methanol-acetonitrile- water (36:27:37 v/v) with flow rate of 1.0 ml/min. Ultra violet (UV) detection of hydrazinocurcumin and internal standard was carried out in dual-wavelength mode at 332 nm and 380 nm, respectively. The linearity of hydrazinocurcumin was found in the range 0.05-5 µg/ml with a correlation coefficient of r² > 0.999. The developed bioanalytical method shown higher inter-day accuracy (98.04-105.94%) and precision (0.89-10.24). The average recoveries of hydrazinocurcumin from rat plasma and various organs were in the range of 96-101.75% and 92.25-99.0%, respectively. The bioanalytical samples shows good stability of hydrazinocurcumin at different storage and handling conditions. In conclusion, this validated HPLC-UV method could be applied effectively for evaluation of hydazinocurcumin for the pharmacokinetic and organ distribution studies.

Hydrazinocurcumin and 5-fluorouracil enhance apoptosis and restrain tumorigenicity of HepG2 cells via disrupting the PTEN-mediated PI3K/Akt signaling pathway

Hydrazinocurcumin (HZC), a curcumin analogue, serves as a tumor suppressor in breast cancer and lung cancer. In this study, we investigate the role and mechanism of HZC in regulating HepG2 cell apoptosis and tumorigenicity, and its synergistic effects with 5-fluorouracil (5-Fu). HepG2 cells were treated with HZC and/or 5-Fu to analyze the possible synergistic effects on cell proliferation, apoptosis and cell cycle distribution in vitro using EdU staining, Hoechst staining and flow cytometry, respectively. For mechanistic investigation we used pic, a phosphatase and tensin homolog (PTEN) inhibitor, and in other studies assessed the expression pattern of PTEN and PI3K/Akt signaling pathway-related genes. Additionally, we tested in vivo effects of HZC and 5-Fu treatment on growth of HepG2 cell tumors in nude mice. We found that HZC or 5-Fu induced apoptosis and repressed proliferation of HepG2 cells by upregulating the expression of PTEN and disrupting the PI3K/Akt signaling pathway activation. Moreover, HZC had a higher pro-apoptotic effect than 5-Fu. HZC and 5-Fu induced HepG2 cell apoptosis and inhibited their tumorigenicity in vivo. Inhibition of PTEN expression activated the PI3K/Akt signaling pathway and reversed the protective effects of HZC or 5-Fu. Thus, HZC and 5-Fu increase PTEN, which blocks the PI3K/Akt signaling pathway, ultimately inducing HepG2 cell apoptosis. Importantly, the synergistic combination of HZC and 5-Fu may present promising strategy for the treatment of HCC.