Pharmacokinetics and Drug-Drug Interaction of Allisartan Isoproxil and Indapamide Sustained-Release Formulation.

Allisartan isoproxil (AI) is an angiotensin II type 1 receptor blocker and be converted into the active substance EXP3174 in vivo. We evaluated the drug-drug interactions of AI and an indapamide sustained-release (Ind SR) preparation, as well as the pharmacokinetic characteristics and safety of AI and Ind SR in healthy subjects. The trial was set up in 6 sequences and 3 cycles, and each cycle contained a 7-day washout period. Subjects received 3 different trial drugs (A, AI; B, Ind SR; C, AI + Ind SR) during 3 different cycles. Twenty-four subjects were enrolled in the clinical trial. Of these, 22 completed the study, 2 subjects dropped out due to adverse events (AEs). For subjects given AI alone or combined with Ind SR, the pharmacogenetic parameters Cmax and the geometric mean ratio of steady state (combined/single) of EXP3174 was 130%. The geometric mean ratio of area under the concentration-time curve over the dosing interval at steady state (combined/single use) was 144.5%. Therefore, the combination of Ind SR had an impact on the pharmacokinetics of AI. Then, the results indicated that the AI combination had no effect on the pharmacokinetics of Ind SR. Serious AEs did not occur. The AEs in this clinical trial were the same as those for AI and Ind SR. Combined administration resulted in 2 cases (2 subjects) of Grade 3 hypotension and 1 case of Grade 3 hypotension with AI alone. Considering that this trial included healthy volunteers, the risk of hypotension was expected to be manageable.

A novel small molecule, (E)-5-(2,4-di-tert-butyl-6-((2,4-dioxothiazolidin-5-ylidene)methyl)phenyl)-5'-methyl-7,7'-dimethoxy-4,4'-bibenzo[d][1,3]dioxole-5,5'-dicarboxylate (7k), alleviates the development of D-galactosamine/lipopolysaccharide-induced acute liver failure by inhibiting macrophage infiltration and regulating cytokine expression.

Acute liver failure (ALF) is a relatively rare liver disorder that leads to the massive death of hepatocytes. Our previous study reported that a novel small-molecule agent, (E)-5-(2,4-di-tert-butyl-6-((2,4-dioxothiazolidin-5-ylidene)methyl)phenyl)-5'-methyl-7,7'-dimethoxy-4,4'-bibenzo[d][1,3]dioxole-5,5'-dicarboxylate (7k), possessed potent anti-inflammatory activity. In the present study, we further evaluated the therapeutic effects of 7k on lipopolysaccharide (LPS)-induced ALF and investigated the mechanisms of action. Our results demonstrated that 7k inhibited the migration of RAW264.7 macrophages, blocked the activity of nuclear factor-κB protein, and dose-dependently down-regulated the production of interleukin (IL)-1ß, tumor necrosis factor-α, and IL-6 as well as their corresponding mRNAs in RAW264.7 cells. Oral administration of 7k at a dose of 50 mg/kg significantly suppressed the serum level of enzyme activity and prevented the damage of liver tissue in D-galactosamine/LPS-induced ALF. Treatment with 7k also remarkably blocked the increase in the number of CD11b(+)- and CD68(+)-positive cells in the liver, and in vivo nuclear factor-κB activity, known to regulate inflammatory responses in many cell types, was effectively inhibited. The serum concentrations and hepatic mRNA expression of proinflammatory cytokines tumor necrosis factor-α, IL-1ß, and IL-6 were markedly down-regulated in mice by the treatment of 7k. In summary, 7k alleviated the development and progression of D-galactosamine/LPS-induced ALF by inhibiting macrophage infiltration and regulating the expression of cytokines.

(Z)2-(5-(4-methoxybenzylidene)-2, 4-dioxothiazolidin-3-yl) acetic acid protects rats from CCl(4) -induced liver injury.

BACKGROUND AND AIM: (Z)2-(5-(4-methoxybenzylidene)-2, 4-dioxothiazolidin-3-yl) acetic acid (MDA) is an aldose reductase (AR) inhibitor. Recent studies suggest that AR contributes to the pathogenesis of inflammation by affecting the nuclear factor κB (NF-κB)-dependent expression of cytokines and chemokines and therefore could be a novel therapeutic target for inflammatory pathology. The current study evaluated the in vivo role of MDA in protecting the liver against injury and fibrogenesis caused by CCl(4) in rats, and the underlying mechanisms. METHODS: A single injection of CCl(4) induced acute hepatitis, and repeated injections were used to induce hepatic fibrosis in rats. Therapeutic efficacy was assessed by comparison of the severity of hepatic injury and fibrosis in MDA-treated rats versus untreated controls. RESULTS: MDA significantly protected the liver from injury by reducing the activity of serum alanine aminotransferase, and improving the histological architecture of the liver. MDA modulated NF-κB-dependent activation of inflammatory cytokines by reducing hepatic mRNA levels of tumor necrosis factor-α, interleukin-1ß, inducible nitric oxide (NO) synthase and transforming growth factor-ß. In addition, MDA attenuated oxidative stress by increasing the content of hepatic glutathione. These favorable changes were associated with suppressed hepatic NF-κB activation by MDA. MDA treatment improved liver fibrosis in rats that received repeated CCl(4) injections. In vitro, MDA attenuated phosphorylation of IκB and activation of NF-κB, and thus prevented biosynthesis of NO in lipopolysaccharide-activated RAW264.7 cells. CONCLUSIONS: The present study suggests that AR is a novel therapeutic anti-inflammatory target for the treatment of hepatitis and liver fibrosis.

Synthesis and evaluation of 5-benzylidenethiazolidine-2,4-dione derivatives for the treatment of non-alcoholic fatty liver disease.

Twenty-two 5-benzylidenethiazolidine-2,4-dione derivatives (TZDs) were synthesized and evaluated for their potency on adipogenesis of 3T3-L1 adipocytes by measuring the expression of adiponectin protein. Among them, compared to rosiglitazone, 3V was found to upregulate the adiponectin protein expression and downregulate the secretion of leptin protein in 3T3-L1 adipocytes at a respective concentration of 10 µM. With respect to high-fat/high-calorie (HF/HC) diet-induced non-alcoholic fatty liver disease (NAFLD) in Wistar rats, oral administration of 3V could reduce liver weight, visceral fat, and improve serum levels of biochemical markers. H&E staining of liver sections validated 3V as a potent hepatoprotective agent for reducing fat deposition against NAFLD.

Pharmacokinetics and Safety of a Single Dose and Multiple Doses of Allisartan Isoproxil, an Angiotensin II Receptor Blocker, in Healthy Chinese People.

Allisartan isoproxil (AI) is a blocker of the angiotensin II type 1 receptor. We evaluated the safety and pharmacokinetics of single- and multiple-dose AI in healthy Chinese individuals. Participants were assigned to receive AI or placebo. Plasma concentration of EXP3174 (carboxylic acid derivative) was measured using liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were determined by noncompartmental methods. Twelve subjects were enrolled, and the ratio of men to women was 5:1. Main pharmacokinetic parameters of EXP3174 after single and multiple doses of AI were a mean maximum concentration in plasma (Cmax ) of 2242 ± 1037 ng/mL and median time to reach Cmax (Tmax ) of 3.5 hours (2.5-8 hours). The median Tmax, at steady state was 4.0 hours (1.5-8 hours). The mean Cmax at steady state (Cmax, SS ) was 2047 ± 1050 ng/mL. In terms of EXP3174, there was no significant difference in the Cmax, SS , area under the curve from time zero to 24 hours of quantifiable concentration at steady state (AUC0-24 SS ), and AUC0-72 after multiple doses of AI. Serious adverse events did not occur. These data suggest that AI is safe and well tolerated in healthy Chinese individuals at a single dose of 480 or 480 mg once daily for 7 days.

Discovery of a Potent, Selective Renal Sodium-Dependent Glucose Cotransporter 2 (SGLT2) Inhibitor (HSK0935) for the Treatment of Type 2 Diabetes.

A new class of potent and highly selective SGLT2 inhibitors is disclosed. Compound 31 (HSK0935) demonstrated excellent hSGLT2 inhibition of 1.3 nM and a high hSGLT1/hSGLT2 selectivity of 843-fold. It showed robust urinary glucose excretion in Sprague-Dawley (SD) rats and affected more urinary glucose excretion in Rhesus monkeys. Finally, an efficient synthetic route has been developed featuring a ring-closing cascade reaction to incorporate a double ketal 1-methoxy-6,8-dioxabicyclo[3.2.1]octane ring system.

Rational design, synthesis, and pharmacological properties of pyranochalcone derivatives as potent anti-inflammatory agents.

24 derivatives (5a-x) derived from natural pyranochalcones (I and II) were designed and evaluated for their inhibitory potency on the production of nitric oxide (NO) in LPS-stimulated RAW264.7 cells. Among them, four compounds (5b, 5d, 5f, and 5h) exhibited more potent inhibitory effects on iNOS activity and iNOS-mediated NO production than a positive control indomethacin. Furthermore, 5b could significantly suppress the progression of carrageenan-induced hind paw edema compared to indomethacin at a dosage of 10 mg/kg/day, and dose-dependently ameliorated the development of adjuvant-induced arthritis (AIA) validated by arthritic scores and H&E staining of joints. In addition, docking study confirmed that 5b was an iNOS inhibitor with binding to the active site of murine iNOS.

(Z)-5-(4-methoxybenzylidene)thiazolidine-2,4-dione protects rats from carbon tetrachloride-induced liver injury and fibrogenesis.

AIM: To evaluate the hepatoprotective roles of (Z)-5-(4-methoxybenzylidene)thiazolidine-2,4-dione (SKLB010) against carbon tetrachloride (CCl4)-induced acute and chronic liver injury and its underlying mechanisms of action. METHODS: In the first experiment, rats were weighed and randomly divided into 5 groups (five rats in each group) to assess the protective effect of SKLB010 on acute liver injury. For induction of acute injury, rats were administered a single intraperitoneal injection of 2 mL/kg of 50% (v/v) CCl4 dissolved in olive oil (1:1). Group 1 was untreated and served as the control group; group 2 received CCl4 for induction of liver injury and served as the model group. In groups 3, 4 and 5, rats receiving CCl4 were also treated with SKLB010 at doses of 25, 50 and 100 mg/kg, respectively. Blood samples were collected at 6, 12 and 24 h after CCl4 intoxication to determine the serum activity of alanine amino transferase. Tumour necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) were determined using enzyme-linked immunosorbent assay. At 24 h after CCl4 injection, liver fibrogenesis was evaluated by hematoxylin-eosin (HE) staining and immunohistochemical analyses. Cytokine transcript levels of TNF-α, IL-1ß and inducible nitric oxide synthase in the liver tissues of rats were measured using a reverse transcriptase reverse transcription-polymerase chain reaction technique. In the second experiment, rats were randomly divided into 2 groups (15 rats in each group), and liver injury in the CCl4-administered groups was induced by a single intraperitoneal injection of 2 mL/kg of 50% (v/v) CCl4 dissolved in olive oil (1:1). The SKLB010-treated groups received oral 100 mg/kg SKLB010 before CCl4 administration. Five rats in each group were sacrificed at 2 h, 6 h, 12 h after CCl4 intoxication and small fortions of livers were rapidly frozen for extraction of total RNA, hepatic proteins and glutathione (GSH) assays. In the hepatic fibrosis model group, rats were randomly divided into 2 groups (5 rats each group). Rats were injected intraperitoneally with a mixture of CCl4 (1 mL/kg body weight) and olive oil [1:1 (v/v)] twice a week for 4 wk. In the SKLB010-treated groups, SKLB010 (100 mg/kg) was given once daily by oral gavage for 4 wk after CCl4 administration. The rats were sacrificed one week after the last injection and the livers from each group were harvested and fixed in 10% formalin for HE and immunohistochemical staining. RESULTS: In this rat acute liver injury model, oral administration of SKLB010 blocked liver tissue injury by down-regulating the serum levels of alanine aminotransferase, suppressing inflammatory infiltration to liver tissue, and improving the histological architecture of liver. SKLB010 inhibited the activation of NF-κB by suppressing the degradation of IκB, and prevented the secretion of pro-inflammatory mediators such as tumor necrosis factor-α, interleukin-1ß, and the reactive free radical, nitric oxide, at the transcriptional and translational levels. In this chronic liver fibrosis model, treatment with 100 mg/kg per day SKLB010 attenuated the degree of hepatic fibrosis and area of collagen, and blocked the accumulation of smooth-muscle actin-expressed cells. CONCLUSION: These results suggest that SKLB010 is a potent therapeutic agent for the treatment of CCl4-induced hepatic injury.

Preparation, characterization, pharmacokinetics, and bioactivity of honokiol-in-hydroxypropyl-ß-cyclodextrin-in-liposome.

Entrapping inclusion complexes in liposomes has been proposed to increase the entrapment efficiency (EE) and stability of liposomes compared with conventional liposomes. In the present study, a stable honokiol-in-hydroxypropyl-ß-cyclodextrin-in-liposome (honokiol-in-HP-ß-CD-in-liposome) was developed as honokiol delivery system by a novel method. The final molar ratio of honokiol/HP-ß-CD/lipid was selected as 1:2:2. The mean particle size was 123.5 nm, the zeta potential was -25.6 mV, and the EE was 91.09 ± 2.76%. The release profile in vitro demonstrated that honokiol is released from honokiol-in-HP-ß-CD-in-liposome with a sustained and slow speed. Crystallographic study indicated that honokiol was first bound within HP-ß-CD and then the inclusion complex was encapsulated within liposomes. Honokiol-in-HP-ß-CD-in-liposome without freeze dry kept stable for at least 6 months at 4°C. Pharmacokinetic study revealed that honokiol-in-HP-ß-CD-in-liposome significantly retarded the elimination and prolonged the residence time in circulating system. The data of bioactivity showed that honokiol-in-HP-ß-CD-in-liposome remained similar antiproliferative activity in A549 and HepG2 tumor cells compared to free honokiol. These results suggested that we had successfully prepared honokiol-in-HP-ß-CD-in-liposome. The novel honokiol formulation was easy to push industrialization forward and might be a potential carrier for honokiol delivery in tumor chemotherapy.

A novel agonist of PPAR-γ based on barbituric acid alleviates the development of non-alcoholic fatty liver disease by regulating adipocytokine expression and preventing insulin resistance.

Non-alcoholic fatty liver disease (NAFLD) is a frequent kind of metabolic syndrome, which included a wide spectrum of liver damage and closely associated with insulin resistance and other metabolic syndromes such as obesity, type II diabetes, hyperglycemia, etc. Recently, a new series of PPARγ ligands based on barbituric acid has been designed, in which 5-(4-(benzyloxy)benzylidene)pyrimidine-2,4,6(1H,3H,5H)-trione (SKLB102) showed a high affinity with PPARγ. The current study aimed to evaluate the protective effect of SKLB102 on NAFLD and investigate the underlying mechanisms. In vivo, oral administration of SKLB102 prevented the pathological development, as demonstrated by reducing liver weight and visceral fat effectively, decreasing the serum levels of alanine transaminase, TNF-α and glucose, diminishing the hepatic triglyceride and malondialdehyde content and recovering the abnormal down-regulation of LDL. Histological examination of liver sections by Oil Red O and H&E staining confirmed the protective effect of SKLB102 on NAFLD. Furthermore, SKLB102 elevated the serum level of adiponectin, reduced the serum level of leptin and prevented insulin resistance. Western blots indicated that SKLB102 increased the hepatic AMPK activities and CPT-1 expression. In vitro, SKLB102 showed the ability of significantly enhancing adiponectin expression and inhibiting leptin expression in 3T3-L1 adipocytes. Furthermore, SKLB102 could promote glucose consumption in HepG2 cells in the presence of 0.1 µM insulin. In conclusion, our current study provided strong evidence that SKLB102 had potent ability to reduce fat deposition and protect liver against NAFLD through regulating adipocytokine expression and preventing insulin resistance, which might be of protective value for the prevention of NAFLD.

Honokiol crosses BBB and BCSFB, and inhibits brain tumor growth in rat 9L intracerebral gliosarcoma model and human U251 xenograft glioma model.

BACKGROUND: Gliosarcoma is one of the most common malignant brain tumors, and anti-angiogenesis is a promising approach for the treatment of gliosarcoma. However, chemotherapy is obstructed by the physical obstacle formed by the blood-brain barrier (BBB) and blood-cerebrospinal fluid barrier (BCSFB). Honokiol has been known to possess potent activities in the central nervous system diseases, and anti-angiogenic and anti-tumor properties. Here, we hypothesized that honokiol could cross the BBB and BCSFB for the treatment of gliosarcoma. METHODOLOGIES: We first evaluated the abilities of honokiol to cross the BBB and BCSFB by measuring the penetration of honokiol into brain and blood-cerebrospinal fluid, and compared the honokiol amount taken up by brain with that by other tissues. Then we investigated the effect of honokiol on the growth inhibition of rat 9L gliosarcoma cells and human U251 glioma cells in vitro. Finally we established rat 9L intracerebral gliosarcoma model in Fisher 344 rats and human U251 xenograft glioma model in nude mice to investigate the anti-tumor activity. PRINCIPAL FINDINGS: We showed for the first time that honokiol could effectively cross BBB and BCSFB. The ratios of brain/plasma concentration were respectively 1.29, 2.54, 2.56 and 2.72 at 5, 30, 60 and 120 min. And about 10% of honokiol in plasma crossed BCSFB into cerebrospinal fluid (CSF). In vitro, honokiol produced dose-dependent inhibition of the growth of rat 9L gliosarcoma cells and human U251 glioma cells with IC(50) of 15.61 µg/mL and 16.38 µg/mL, respectively. In vivo, treatment with 20 mg/kg body weight of honokiol (honokiol was given twice per week for 3 weeks by intravenous injection) resulted in significant reduction of tumor volume (112.70±10.16 mm(3)) compared with vehicle group (238.63±19.69 mm(3), P = 0.000), with 52.77% inhibiting rate in rat 9L intracerebral gliosarcoma model, and (1450.83±348.36 mm(3)) compared with vehicle group (2914.17±780.52 mm(3), P = 0.002), with 50.21% inhibiting rate in human U251 xenograft glioma model. Honokiol also significantly improved the survival over vehicle group in the two models (P<0.05). CONCLUSIONS/SIGNIFICANCE: This study provided the first evidence that honokiol could effectively cross BBB and BCSFB and inhibit brain tumor growth in rat 9L intracerebral gliosarcoma model and human U251 xenograft glioma model. It suggested a significant strategy for offering a potential new therapy for the treatment of gliosarcoma.

Synthesis and biological evaluation of novel dimethyl[1,1'-biphenyl]-2,2'-dicarboxylate derivatives containing thiazolidine-2,4-dione for the treatment of concanavalin A-induced acute liver injury of BALB/c mice.

In this paper, we reported the synthesis of bifendate derivatives and evaluation of anti-inflammatory activity by detecting the production of the Nitric Oxide (NO) in the lipopolysaccharide(LPS)-stimulated RAW 264.7 cell lines. Among the newly derivatives, compound 7k was the most potent one and two other compounds (7e and 7f) also exhibited greater anti-inflammatory activity than bifendate. Further in vivo studies confirmed that 7k significantly and dose-dependently inhibited carrageenan-induced paw edema and decreased the serum levels of alanine aminotransaminase, and aspartate aminotransaminase in concanavalin A-induced hepatitis model. Histopathological evaluation demonstrated that 7k has better hepatoprotective effect on acute liver injury induced by concanavalin A than bifendate, suggesting that 7k is a potential drug candidate for the treatment of hepatic injuries.

Improved solubility and pharmacokinetics of PEGylated liposomal honokiol and human plasma protein binding ability of honokiol.

PEGylated liposomal honokiol had been developed with the purpose of improving the solubility and pharmacokinetics compared with free honokiol. Human plasma protein binding ability of honokiol was also investigated. PEGylated liposomal honokiol was prepared by thin film evaporation-sonication method. Its mean particle size was 98.68 nm, mean zeta potential was -20.6 mV and encapsulation efficiency were 87.68±1.56%. The pharmacokinetics of PEGylated liposomal honokiol was studied after intravenous administration in Balb/c mice. There were significant differences of parameters T(1/2ß) and AUC(0→∞) between them and liposome lengthened T(1/2ß) and AUC(0→∞) values. The mean T(1/2ß) value of PEGylated liposomal honokiol and free honokiol were 26.09 min and 13.46 min, respectively. The AUC(0→∞) ratio of PEGylated liposomal honokiol to free honokiol was about 1.85-fold (219.24 µg/mL min/118.68 µg/mL min) (P=0.000). Examination of protein binding ability showed that honokiol with 0.5, 8.0 and 20 µg/mL concentrations in human plasma achieved the percent of bound between 60% and 65%. The results suggested that PEGylated liposomal honokiol improved the solubility, increased the drug concentration in plasma, and withstanded the clearance. Besides, the percent of protein bound of honokiol in human plasma was between 60% and 65%.