Differential effects of OATP2B1 on statin accumulation and toxicity in a beta cell model.

An increased risk of new-onset diabetes mellitus has been recently reported for statin therapy, and experimental studies have shown reduced glucose-stimulated insulin secretion (GSIS) and mitochondrial dysfunction in beta cells with effects differing among agents. Organic anion transporting polypeptide (OATP) 2B1 contributes to hepatic uptake of rosuvastatin, atorvastatin and pravastatin, three known substrates. Since OATP2B1 is present in beta cells of the human pancreas, we investigated if OATP2B1 facilitates the local accumulation of statins in a rat beta cell model INS-1 832/13 (INS-1) thereby amplifying statin-induced toxicity. OATP2B1 overexpression in INS-1 cells via adenoviral transduction showed 2.5-, 1.8- and 1.4-fold higher cellular retention of rosuvastatin, atorvastatin and pravastatin, respectively, relative to LacZ control, while absolute intracellular concentration was about twice as high for the lipophilic atorvastatin compared to the more hydrophilic rosuvastatin and pravastatin. After 24 h statin treatment at high concentrations, OATP2B1 enhanced statin toxicity involving activation of intrinsic apoptosis (caspase 3/7 activation) and mitochondrial dysfunction (NADH dehydrogenase activity) following rosuvastatin and atorvastatin, which was partly reversed by isoprenoids. OATP2B1 had no effect on statin-induced reduction in GSIS, mitochondrial electron transport chain complex expression or caspase 9 activation. We confirmed a dose-dependent reduction in insulin secretion by rosuvastatin and atorvastatin in native INS-1 with a modest change in cellular ATP. Collectively, our results indicate a role of OATP2B1, which is abundant in human beta cells, in statin accumulation and statin-induced toxicity but not insulin secretion of rosuvastatin and atorvastatin in INS-1 cells.

Pharmacokinetic and pharmacodynamic exploration of various combinations of tegoprazan immediate and delayed-release formulations.

AIMS: The new modified-release formulation of tegoprazan, a novel potassium-competitive acid blocker, is expected to improve the management of acid-related disease, including nocturnal acid breakthrough, by prolonging the duration of acid suppression. This study aimed to explore the pharmacokinetics (PK) and pharmacodynamics (PD) of various combinations of tegoprazan with immediate-release (IR) and delayed-release (DR) formulations. METHODS: A three-cohort, open-label, randomized, single-dose, three-treatment, six-sequence, three-period crossover study was conducted. Various combinations of tegoprazan IR and DR formulations (50, 75 or 100 mg) were administered orally once per period. The 24-h intragastric pH was monitored before and after each administration. PK blood samples were collected for up to 48 h. PK and PD were compared among treatments. RESULTS: Eighteen healthy Korean subjects completed the study. All treatment groups showed intragastric pH above 4 approximately 1 h following tegoprazan administration. Among the various combinations, the IR and DR combination at a 1:1 ratio induced greater gastric acid suppression (%Time pH ≥ 4) than IR alone in each dose group, both for 24 h (50 mg; 59% vs. 52%, P = .2188, 95% confidence interval [CI] -6.92-22.27, 100 mg; 85% vs. 70%, P < .05, 95% CI 8.92-22.19) and at night (50 mg; 27% vs. 16%, P = .1563, 95% CI -11.79-37.71, 100 mg; 77% vs. 49%, P < .05, 95% CI 16.14-42.98), with similar systemic exposure. CONCLUSIONS: The combinatorial tegoprazan in the IR and DR 1:1 ratio formulation was found to induce stronger gastric acid suppression throughout the day and at night, compared to the conventional IR formulation.

Identification of a sensitive urinary biomarker, selenium-binding protein 1, for early detection of acute kidney injury.

Acute kidney injury (AKI) is associated with increased mortality rate in patients but clinically available biomarkers for disease detection are currently not available. Recently, a new biomarker, selenium-binding protein 1 (SBP1), was identified for detection of nephrotoxicity using proteomic analysis. The aim of this study was to assess the sensitivity of urinary SBP1 levels as an early detection of AKI using animal models such as cisplatin or ischemia/reperfusion (I/R). Sprague-Dawley rats were injected with cisplatin (6 mg/kg, once i.p.) and sacrificed at 1, 3, or 5 days after treatment. Ischemia was achieved by bilaterally occluding both kidneys with a microvascular clamp for 45 min and verified visually by a change in tissue color. After post-reperfusion, urine samples were collected at 9, 24, and 48 hr intervals. Urinary excretion of protein-based biomarkers was measured by Western blot analysis. In cisplatin-treated rats, mild histopathologic alterations were noted at day 1 which became severe at day 3. Blood urea nitrogen (BUN) and serum creatinine (SCr) levels were significantly increased at day 3. Levels of urinary excretion of SBP1, neutrophil gelatinase-associated lipocalin (NGAL), and a tissue inhibitor of metalloproteinase-1 (TIMP-1) were markedly elevated at day 3 and 5 following drug treatment. In the vehicle-treated I/R group, serum levels of BUN and SCr and AST activity were significantly increased compared to sham. Urinary excretion of SBP1 and NGAL rose markedly following I/R. The urinary levels of SBP1, NGAL, TIMP-1, and KIM-1 proteins excreted by AKI patients and normal subjects were compared. Among these proteins, a marked rise in SBP1 was observed in urine of patients with AKI compared to normal subjects. Based upon receiver-operator curves (ROC), SBP1 displayed a higher area under the curve (AUC) scores than levels of SCr, BUN, total protein, and glucose. In particular, SBP1 protein was readily detected in small amounts of urine without purification. Data thus indicate that urinary excretion of SBP1 may be useful as a reliable biomarker for early diagnosis of AKI in patients.

Development of a Fast Onset Proton Pump Inhibitor: Comparison of Fixed-Dose Combination of Rabeprazole and Sodium Bicarbonate (YPI-011) to the Conventional Enteric-Coated Rabeprazole.

Purpose: Proton pump inhibitors (PPIs) are the first-line therapy for gastroesophageal reflux disorder (GERD). Unlike conventional PPIs, non-enteric coated PPIs with antacid salt enable a faster acid suppression through the rapid absorption of the PPI. YPI-011 is a newly developed fixed-dose combination of a rabeprazole with sodium bicarbonate (NaHCO3). This study compared the pharmacokinetics (PKs) and pharmacodynamics (PDs) of YPI-011 to the conventional enteric-coated rabeprazole (Pariet®). Materials and Methods: A randomized, open-label, two-treatment, two-sequence crossover study was conducted with two different doses (10 and 20 mg) and 44 subjects in each group. They randomly received either a test or reference treatment for 7 days in the first period and the other treatment in the second period. Blood samples for the PK analysis were taken after the single- and multiple-dose. Intragastric pH monitoring for the PD analysis was implemented for baseline and after the single- and multiple-dose. Results: Gastric acid suppression evaluated by the percentage decrease from baseline in the integrated gastric acidity for a 24-hour interval after the multiple-dose was similar between the treatments in both dose groups. The systemic exposure of rabeprazole at steady state after the multiple-dose was also similar between the treatments in both dose groups. The time to reach the maximum rabeprazole concentration was faster in the test treatment. The PK-PD relationship of PPI is well known, and the faster absorption of rabeprazole resulted in a more rapid mode of action in acid suppression. Conclusion: The fixed dose combination of rabeprazole with NaHCO3 showed a faster absorption and consequently, a more rapid gastric acid suppression with a similar systemic exposure of rabeprazole at steady state compared to the conventional enteric-coated rabeprazole.

Comparative Pharmacokinetics/Pharmacodynamics of Fixed-Dose Combination of Esomeprazole and Calcium Carbonate (AD-206) to the Conventional Esomeprazole.

PURPOSE: Proton pump inhibitors (PPIs) are used for the treatment of acid-related disorders. Demands for enhanced stability and faster onset led to the development of AD-206, a fixed-dose combination of a PPI (esomeprazole) with an antacid salt (calcium carbonate). This study compared the pharmacokinetics (PKs) and pharmacodynamics (PDs) of AD-206 (Addpharma) with conventional esomeprazole (Nexium®, AstraZeneca). MATERIALS AND METHODS: A randomized, open-label, two-treatment, two-sequence crossover study was conducted with 2 different doses of esomeprazole at 20 and 40 mg with a fixed calcium carbonate dose of 600 mg in AD-206. Forty-four subjects were included in each dose group and randomly received either AD-206 or the conventional esomeprazole for 7 consecutive days in each period. After a single- and multiple-dose, blood samples for the PK analysis were analyzed, and 24-hour intragastric pH monitoring was conducted. RESULTS: The systemic exposure of esomeprazole after a multiple-dose of AD-206 was similar to that of the conventional esomeprazole in both doses, but the time to reach the peak concentration was faster in AD-206. The percentage decrease from baseline in the integrated gastric acidity for a 24-hour interval after the dose was not significantly different between the AD-206 and the conventional esomeprazole after a single- and multiple-dose for both doses, and the time to reach pH 4 was faster for AD-206. CONCLUSION: AD-206 showed a similar systemic exposure and suppression of gastric acid secretion after a multiple-dose compared to the conventional esomeprazole.

Acaricidal activity of butylidenephthalide identified in Cnidium officinale rhizome against dermatophagoides farinae and dermatophagoides pteronyssinus (Acari: Pyroglyphidae).

The acaricidal activity of materials derived from the rhizome of Cnidium officinale against adults of Dermatophagoides farinae and Dermatophagoides pteronyssinus was examined using direct contact application and fumigation methods and compared with that of benzyl benzoate and N,N-diethyl-m-toluamide (DEET). The active constituent of the Cnidium rhizome was identified as butylidenephthalide by spectroscopic analyses. Responses varied with dose. On the basis of 24-h LD(50) values, the acaricidal activity of butylidenephthalide (6.77 microg/cm(2)) against D. farinae adults was comparable to that of benzyl benzoate (8.54 microg/cm(2)). Very low activity was observed with DEET (37.59 microg/cm(2)). Against D. pteronyssinus adults, butylidenephthalide (6.46 microg/cm(2)) and benzyl benzoate (6.68 microg/cm(2)) were equitoxic. DEET (17.98 microg/cm(2)) was relatively inactive. The typical poisoning symptom of butylidenephthalide was lethargy of treated mites, leading to death without knockdown, whereas benzyl benzoate and DEET caused death following uncoordinated behavior. In a fumigation test with both mite species, butylidenephthalide was much more effective in closed containers than open ones. Naturally occurring C. officinale rhizome-derived materials merit further study as potential house dust mite control agents or lead compounds.

Acaricidal activity of Cnidium officinale rhizome-derived butylidenephthalide against Tyrophagus putrescentiae (Acari: Acaridae).

The acaricidal activity of materials derived from the rhizome of Cnidium officinale Makino against Tyrophagus putrescentiae Schrank adults was examined using direct contact application and fumigation methods, and compared with that of benzyl benzoate and N,N-diethyl-m-toluamide (DEET). The biologically active constituent of the Cnidium rhizome was identified as butylidenephthalide by spectroscopic analyses. On the basis of 24-h LD50 values, acaricidal activity was more pronounced with butylidenephthalide (5.80 microg cm(-2)) than with benzyl benzoate (9.75 microg cm(-2)) and DEET (16.26 microg cm(-2)). In typical poisoning symptoms, butylidenephthalide resulted in lethargy of treated mites, leading to death without knockdown, whereas benzyl benzoate and DEET caused death associated with uncoordinated behaviour. In a fumigation test with T. putrescentiae adults, butylidenephthalide was much more effective in closed containers than in open ones, indicating that the effects of this compound were largely due to action in the vapour phase. Naturally occurring C. officinale rhizome-derived materials merit further study as potential T. putrescentiae control agents or as lead compounds.