Chromatographic study of sitagliptin and ertugliflozin under quality-by-design paradigm

Abstract The present study entails the systematic development and validation of a stability-indicating RP-HPLC method for the analysis of sitagliptin and ertugliflozin in a fixed-dose combination. Analytical quality by design (AQbD) concepts were used to define critical method variables, employing Pareto risk assessment and a Placket-Burman screening design, preceded by a Box-Behnken design with response surface analysis to optimise critical method parameters such as % acetonitrile (X1), buffer pH (X2) and column oven temperature (X3). Multiple response optimisation (Derringer's desirability) of variables was accomplished by studying critical analytical attributes, such as resolution, retention time and theoretical plates. The title analytes were separated effectively on a PRONTOSIL C18 column at 37 °C using a mobile phase of acetonitrile:acetate buffer, pH 4.4 (36:64 percent v/v), pumped at a flow rate of 1 mL/min, and UV detection at 225 nm. Linearity was observed over a concentration range of 25-150 µg/mL and 3.75-22.5 µg/mL at retention times of 2.82 and 3.92 min for sitagliptin and ertugliflozin, respectively. The method obeyed all validation parameters of the ICH Q2(R1) guidelines. The proposed robust method allows the study of the selected drugs in pharmaceutical dosage forms as well as in drug stability studies under various stress conditions.

Effects of treatment with sitagliptin on hepatotoxicity induced by acetaminophen in mice

Up to date, the management of hepatotoxicity induced by a suicidal or unintentional overdose of acetaminophen (APAP) remains a therapeutic challenge. The present study aimed to elucidate the potential effect of sitagliptin, a DPP-4 inhibitor, to ameliorate the acute injurious effects of acetaminophen on the liver. APAP toxicity was induced in mice by an intraperitoneal injection of APAP (400 mg/kg). The effect of treatment with sitagliptin, initiated 5 days prior to APAP injection, was evaluated. Serum indices of hepatotoxicity, oxidative stress markers in liver tissues, serum IL-1ß, and TNF-α in addition to hepatic- NF-E2-related factor-2 (Nrf2) were determined. Our results showed that APAP induced marked hepatic injury as evidenced by an increase in serum levels of ALT and AST, in addition to the deterioration of histological grading. Oxidative stress markers, serum TNF-α, and IL-1ß were also elevated. Sitagliptin successfully ameliorated the histological changes induced by APAP, improving liver function tests and liver oxidant status accompanied with a marked increase in Nrf2 level in hepatic tissues. Thus, the hepatoprotective effects of sitagliptin in this animal model seem to involve Nrf2 modulation, coincidental with its anti-inflammatory and antioxidant effects