Discovery of Highly Potent Solute Carrier 13 Member 5 (SLC13A5) Inhibitors for the Treatment of Hyperlipidemia

In the face of escalating metabolic disease prevalence, largely driven by modern lifestyle factors, this study addresses the critical need for novel therapeutic approaches. We have identified the sodium-coupled citrate transporter (NaCT or SLC13A5) as a target for intervention. Utilizing rational drug design, we developed a new class of SLC13A5 inhibitors, anchored by the hydroxysuccinic acid scaffold, refining the structure of PF-06649298. Among these, LBA-3 emerged as a standout compound, exhibiting remarkable potency with an IC50 value of 67 nM, significantly improving upon PF-06649298. In vitro assays demonstrated LBA-3's efficacy in reducing triglyceride levels in OPA-induced HepG2 cells. Moreover, LBA-3 displayed superior pharmacokinetic properties and effectively lowered triglyceride and total cholesterol levels in diverse mouse models (PCN-stimulated and starvation-induced), without detectable toxicity. These findings not only spotlight LBA-3 as a promising candidate for hyperlipidemia treatment but also exemplify the potential of targeted molecular design in advancing metabolic disorder therapeutics.

Phase 1, Single- and Multiple-Ascending-Dose, Food-Effect, and East Asian Subject Studies to Assess the Pharmacokinetics, Safety, and Tolerability of Bempedoic Acid, a Selective Inhibitor of Adenosine Triphosphate Citrate Lyase

Bempedoic acid is an adenosine triphosphate citrate lyase inhibitor that lowers low-density lipoprotein cholesterol by inhibiting cholesterol synthesis and upregulating hepatic low-density lipoprotein receptor expression. After oral dosing, bempedoic acid was readily absorbed, attaining maximum concentrations with a median time of 3.5 hours, and may be taken without regard to food. Steady-state oral pharmacokinetics in healthy adults receiving bempedoic acid at the approved 180 mg/day dose were characterized by mean maximum concentration of 20.6 µg/mL, area under the concentration-time curve over 24 hours of 289 µg·h/mL, and elimination half-life of 21.1 hours. Multiple-dose pharmacokinetics were linear at bempedoic acid doses of 120-220 mg/day. Circulating concentrations of the active metabolite ESP15228 were 18.0% of bempedoic acid concentrations on average. Comparisons of bempedoic acid 180 mg/day pharmacokinetics after single and multiple dosing revealed no clinically meaningful differences between Japanese, Chinese, and Western subjects. Mean estimates of bempedoic acid elimination half-life in Japanese (25.2 hours) and Chinese (20.0 hours) subjects were comparable to Western subjects (23.9 hours) following 14 days of once-daily dosing. Bempedoic acid was generally safe and well tolerated up to a dose of 220 mg/day across the study populations described herein.

Severe adverse cutaneous reactions induced by gefitinib combined with antihypertensive and antihyperlipidemic drugs in lung cancer: a case report

The incidence of lung cancer is increasing yearly worldwide, and targeted medicines are the main choice for lung cancer patients. However, there has been no relevant research about the analysis and adjustment of drug combinations for cancer patients with hypertension and hyperlipidemia until now. Here, we reported a case of medicine adjustment for a patient of lung cancer with hypertension and hyperlipidemia. The patient was diagnosed as right lung adenocarcinoma with lymph node metastasis and continued taking gefitinib tablets to maintain therapeutic efficacy after the end of chemotherapy. Severe paronychia and a high plasma concentration of gefitinib were noticed when the patient visited the hospital for reexamination. The clinical pharmacist found that the patient took nifedipine sustained-release tablets and simvastatin tablets simultaneously, and these medicines were all substrates of CYP3A4. The clinical pharmacist suggested replacing the medicines for hypertension and hyperlipidemia with valsartan capsules (Diovan) and rosuvastatin calcium tablets (Crestor), respectively. The adverse cutaneous reactions were greatly relieved, and the plasma concentration of gefitinib was decreased when another reexamination was performed. Therapeutic drug monitoring was an important method in our case and provided valuable information to develop individualized treatment strategies. For cancer patients suffering from other diseases such as hypertension and hyperlipidemia, it is necessary to pay special attention to the drug-drug interactions and metabolic pathways among drug combinations.

Bempedoic acid. Mechanism of action and pharmacokinetic and pharmacodynamic properties

Bempedoic acid acts by inhibiting adenosine triphosphate-citrate lyase (ACL) and consequently cholesterol biosynthesis, leading to increased expression of LDL receptors and increasing low-density lipoproteins (LDL-C) plasma clearence. It is a prodrug for oral administration with intracellular activation. It is activatedin liver cells and to a lesser extent in kidney cells, being absent in adipose tissue and muscle cells. Therefore, unlike statins, its potential myotoxic effect is very limited. It has recently been approved as a lipid-lowering drug in combination with diet, with statins, or with other lipid-lowering drugs in patients with hypercholesterolaemia, mixed dyslipidaemia, statin intolerance, or when these are contraindicated. The marketing of bempedoic acid implies, in clinical practice, having a new family of lipid-lowering drugs.

Effects of Renal Impairment on the Pharmacokinetics, Efficacy, and Safety of Inclisiran: An Analysis of the ORION-7 and ORION-1 Studies

OBJECTIVE

To investigate the pharmacodynamic properties of inclisiran, a small interfering RNA targeting proprotein convertase subtilisin-kexin type 9 (PCSK9), in individuals with normal renal function and renal impairment (RI).

PATIENTS AND METHODS

The analysis included participants with normal renal function and mild, moderate, and severe RI from the phase 1 ORION-7 renal study (n=31) and the phase 2 ORION-1 study (n=247) who received 300 mg of inclisiran sodium or placebo.

RESULTS

In ORION-7, PCSK9 values were reduced at day 60 in the normal renal function group (68.1%±12.4%), mild RI group (74.2%±12.3%), moderate RI group (79.8%±4.9%), and severe RI group (67.9%±16.4%) (P<.001 vs placebo in all groups). Low-density lipoprotein cholesterol levels were significantly reduced versus placebo: normal renal function, 57.6%±10.7%; mild RI, 35.1%±13.5%; moderate RI, 53.1%±21.3%; severe RI, 49.2%±26.6% (P<.001 for all). In ORION-1, PCSK9 level reductions at day 180 were 48.3% to 58.6% in the 300-mg single-dose groups and 67.3% to 73.0% in the 300-mg 2-dose groups (P<.001 vs placebo in all groups). The corresponding low-density lipoprotein cholesterol level reductions were 35.7% to 40.2% in the 300-mg single-dose groups and 50.9% to 58.0% in the 300 mg 2-dose groups (P<.001 vs placebo in all groups). In ORION-7, exposure to inclisiran was proportionally greater in individuals with increasing RI; inclisiran was undetectable in plasma 48 hours after administration in any group.

CONCLUSION

The pharmacodynamic effects and safety profile of inclisiran were similar in study participants with normal and impaired renal function. Dose adjustments of inclisiran are not required in these patients.

TRIAL REGISTRATION

clinicaltrials.gov Identifiers: NCT02597127 and NCT03159416.

Antihyperlipidemic effect of iridoid glycoside deacetylasperulosidic acid isolated from the seeds of Spermacoce hispida L. - A traditional antiobesity herb

ETHNOBOTANICAL RELEVANCE

The interest on herbal health supplements for obesity is increasing globally. Our previous ethnobotanical survey in Tiruvallur district, Tamil Nadu, India indicated the use of Spermacoce hispida L. seeds for the treatment of obesity.

AIM OF THE STUDY

This study was aimed to validate the traditional claim and to identify the antihyperlipidemic principle in the seeds of Spermacoce hispida using bioassay guided fractionation method.

METHODS

Bioassay monitored fractionation of the aqueous extract from Spermacoce hispida seeds was carried out using triton WR 1339 induced hyperlipidemic animals. It yielded deacetylasperulosidic acid (DAA) as the active ingredient. Pharmacokinetic properties of DAA were predicted using DataWarrior and SwissADME tools. In vitro antiobesity and antihyperlipidemic effects of DAA were evaluated in 3T3L1 preadipocytes and HepG2 cells, respectively. The chronic antihyperlipidemic efficacy of DAA was evaluated in high fat diet fed rats.

RESULTS

DAA did not show any mutagenic and tumorigenic properties. It bound with PPARα with comparable ligand efficiency as fenofibrate. The treatment with DAA significantly lowered the proliferation of matured adipocytes, but not preadipocytes. The treatment of steatotic HepG2 cells with DAA significantly decreased the LDH leakage by 43.03% (P < 0.05) at 50 μM concentration. In triton WR 1339 induced hyperlipidemic animals, the treatment with 50 mg/kg dose significantly lowered the TC, TG and LDL-c levels by 40.27, 46.00 and 63.65% respectively. In HFD fed animals, the treatment at 10 mg/kg decreased BMI and AC/TC ratio without altering SRBG. It also improved serum lipid, transaminases and phosphatases levels of HFD fed animals. The treatment lowered adipocyte hypertrophy and steatosis of hepatocytes.

CONCLUSION

This preliminary report supported the traditional use of Spermacoce hispida for the treatment of obesity. Further detailed investigations on the long term safety, efficacy and molecular mode of action of Spermacoce hispida and DAA will throw more light on their usefulness for the management of obesity.

Impact of drug distribution into adipose on tissue function: The cholesteryl ester transfer protein (CETP) inhibitor anacetrapib as a test case

Anacetrapib is an inhibitor of cholesteryl ester transfer protein (CETP) previously under development as a lipid-modifying agent that reduces LDL-cholesterol and increases HDL-cholesterol in hypercholesterolemic patients. Anacetrapib demonstrates a long terminal half-life and accumulates in adipose tissue, which contributes to a long residence time of anacetrapib. Given our previous report that anacetrapib distributes into the lipid droplet of adipose tissue, we sought to understand whether anacetrapib affected adipose function, using a diet-induced obese (DIO) mouse model. Following 20 weeks of treatment with anacetrapib (100 mg/kg/day), levels of the drug increased to approximately 0.6 mmol/L in white adipose tissue. This level of anacetrapib was not associated with any impairment in adipose functionality as evidenced by a lack of any reduction in biomarkers of adipose functionality (plasma adiponectin, leptin, insulin; adipose adiponectin, leptin mRNA). In DIO wild-type (WT) mice treated with anacetrapib for 2 weeks and then subjected to 30% food restriction during washout to induce weight loss (18%) and fat mass loss (7%), levels of anacetrapib in adipose and plasma were not different between food restricted and ad lib-fed mice. These data indicate that despite deposition and long-term residence of ~0.6 mmol/L levels of anacetrapib in adipose tissue, adipose tissue function appears to be unaffected in mice. In addition, these data also indicate that even with severe caloric restriction and acute loss of fat mass, anacetrapib does not appear to be mobilized from the fat depot, thereby solidifying the role of adipose as a long-term storage site of anacetrapib.

Surface stabilized atorvastatin nanocrystals with improved bioavailability, safety and antihyperlipidemic potential

Atorvastatin, a favored option for hyperlipidemia exhibits the problem of poor gastric solubility and low absolute bioavailability (12%) along with higher pre-systemic clearance (>80%). Therefore, to circumvent these limitations, atorvastatin nanocrystals were prepared using poloxamer-188 as stabilizer via high pressure homogenization technique followed by lyophilization. Various variables like drug to poloxamer-188 ratio, homogenization cycle, homogenization pressure, type and concentration of cryoprotectant were optimized to achieve uniform nanosized crystals with good dispersibility. Solid state characterization by ATR-FTIR and DSC revealed no incompatible physicochemical interaction between drug and excipients in formulation while DSC and PXRD collectively corroborated the reduced crystallinity of drug in nanocrystals. Size analysis and SEM confirmed nanometric size range of nanocrystals (225.43 ± 24.36 nm). Substantial improvement in gastric solubility (~40 folds) and dissolution rate of drug in nanocrystals was observed. Pharmacokinetic study in wistar rats revealed significant improvement in oral bioavailability (~2.66 folds) with atorvastatin nanocrystals compared to pure drug. Furthermore, reduction in serum total lipid cholesterol, LDL and triglyceride content justified the effectiveness of formulation at 50% less dose of atorvastatin along with improved plasma safety profile in comparison of pure drug. In conclusion, atorvastatin nanocrystals are safe and efficacious drug delivery system confirming potent competence in treatment of hyperlipidemic conditions with ease of scalability for commercialization.

Genetic Variants in HSD17B3, SMAD3, and IPO11 Impact Circulating Lipids in Response to Fenofibrate in Individuals With Type 2 Diabetes

Individuals with type 2 diabetes (T2D) and dyslipidemia are at an increased risk of cardiovascular disease. Fibrates are a class of drugs prescribed to treat dyslipidemia, but variation in response has been observed. To evaluate common and rare genetic variants that impact lipid responses to fenofibrate in statin-treated patients with T2D, we examined lipid changes in response to fenofibrate therapy using a genomewide association study (GWAS). Associations were followed-up using gene expression studies in mice. Common variants in SMAD3 and IPO11 were marginally associated with lipid changes in black subjects (P < 5 × 10-6 ). Rare variant and gene expression changes were assessed using a false discovery rate approach. AKR7A3 and HSD17B13 were associated with lipid changes in white subjects (q < 0.2). Mice fed fenofibrate displayed reductions in Hsd17b13 gene expression (q < 0.1). Associations of variants in SMAD3, IPO11, and HSD17B13, with gene expression changes in mice indicate that transforming growth factor-beta (TGF-β) and NRF2 signaling pathways may influence fenofibrate effects on dyslipidemia in patients with T2D.

A mechanism-based pharmacokinetic model of fenofibrate for explaining increased drug absorption after food consumption

BACKGROUND

Oral administration of drugs is convenient and shows good compliance but it can be affected by many factors in the gastrointestinal (GI) system. Consumption of food is one of the major factors affecting the GI system and consequently the absorption of drugs. The aim of this study was to develop a mechanistic GI absorption model for explaining the effect of food on fenofibrate pharmacokinetics (PK), focusing on the food type and calorie content.

METHODS

Clinical data from a fenofibrate PK study involving three different conditions (fasting, standard meals and high-fat meals) were used. The model was developed by nonlinear mixed effect modeling method. Both linear and nonlinear effects were evaluated to explain the impact of food intake on drug absorption. Similarly, to explain changes in gastric emptying time for the drug due to food effects was evaluated.

RESULTS

The gastric emptying rate increased by 61.7% during the first 6.94 h after food consumption. Increased calories in the duodenum increased the absorption rate constant of the drug in fed conditions (standard meal = 16.5%, high-fat meal = 21.8%) compared with fasted condition. The final model displayed good prediction power and precision.

CONCLUSIONS

A mechanistic GI absorption model for quantitatively evaluating the effects of food on fenofibrate absorption was successfully developed, and acceptable parameters were obtained. The mechanism-based PK model of fenofibrate can quantify the effects of food on drug absorption by food type and calorie content.

The antihyperlipidemic effects of fullerenol nanoparticles via adjusting the gut microbiota in vivo

BACKGROUND

Nanoparticles (NPs) administered orally will meet the gut microbiota, but their impacts on microbiota homeostasis and the consequent physiological relevance remain largely unknown. Here, we describe the modulatory effects and the consequent pharmacological outputs of two orally administered fullerenols NPs (Fol1 C60(OH)7(O)8 and Fol113 C60(OH)11(O)6) on gut microbiota.

RESULTS

Administration of Fol1 and Fol113 NPs for 4 weeks largely shifted the overall structure of gut microbiota in mice. The bacteria belonging to putative short-chain fatty acids (SCFAs)-producing genera were markedly increased by both NPs, especially Fol1. Dynamic analysis showed that major SCFAs-producers and key butyrate-producing gene were significantly enriched after treatment for 7-28 days. The fecal contents of SCFAs were consequently increased, which was accompanied by significant decreases of triglycerides and total cholesterol levels in the blood and liver, with Fol1 superior to Fol113. Under cultivation in vitro, fullerenols NPs can be degraded by gut flora and exhibited a similar capacity of inulin to promote SCFA-producing genera. The differential effects of Fol1 and Fol113 NPs on the microbiome may be attributable to their subtly varied surface structures.

CONCLUSIONS

The two fullerenol NPs remarkably modulate the gut microbiota and selectively enrich SCFA-producing bacteria, which may be an important reason for their anti-hyperlipidemic effect in mice.

Effects of type 2 diabetes mellitus on the pharmacokinetics of berberine in rats

CONTEXT

Berberine is an active alkaloid isolated from Rhizoma coptidis [Coptis chinensis Franch. (Ranunculaceae)] that is widely used for the treatment of diabetes, hyperlipidemia and hypertension. However, the pharmacokinetics of berberine in normal rats and type 2 diabetes mellitus (T2DM) model rats are not clear.

OBJECTIVE

This study compares the pharmacokinetics of berberine between normal and T2DM model rats.

MATERIALS AND METHODS

The T2DM model rats were fed with high fat diet for 4 weeks, induced by low-dose (30 mg/kg) streptozotocin for 72 h and validated by determining the peripheral blood glucose level. Rats were orally treated with berberine at a dose of 20 mg/kg and then berberine concentration in rat plasma was determined by employing a sensitive and rapid LC-MS/MS method.

RESULTS

The significantly different pharmacokinetic behaviour of berberine was observed between normal and T2DM model rats. When compared with the normal group, C_max, t_1/2 and AUC_(0-t) of berberine were significantly increased in the model group (17.35 ± 3.24 vs 34.41 ± 4.25 μg/L; 3.95 ± 1.27 vs 9.29 ± 2.75 h; 151.21 ± 23.96 vs 283.81 ± 53.92 μg/h/L, respectively). In addition, oral clearance of berberine was significantly decreased in the model group (134.73 ± 32.15 vs 62.55 ± 16.34 L/h/kg).

DISCUSSION AND CONCLUSION

In T2DM model rats, the pharmacokinetic behaviour of berberine was significantly altered, which indicated that berberine dosage should be modified in T2DM patients.

Once-weekly administration of a long-acting fibroblast growth factor 21 analogue modulates lipids, bone turnover markers, blood pressure and body weight differently in obese people with hypertriglyceridaemia and in non-human primates

AIMS

To assess the safety, tolerability, pharmacokinetics and pharmacodynamics of PF-05231023, a long-acting fibroblast growth factor 21 (FGF21) analogue, in obese people with hypertriglyceridaemia on atorvastatin, with or without type 2 diabetes.

METHODS

Participants received PF-05231023 or placebo intravenously once weekly for 4 weeks. Safety (12-lead ECGs, vital signs, adverse events [AEs], laboratory tests) and longitudinal weight assessments were performed. Blood samples were collected for pharmacokinetic and pharmacodynamic analyses. Cardiovascular safety studies were also conducted in telemetered rats and monkeys. Blood pressure (BP; mean, systolic and diastolic) and ECGs were monitored.

RESULTS

A total of 107 people were randomized. PF-05231023 significantly decreased mean placebo-adjusted fasting triglycerides (day 25, 33%-43%) and increased HDL cholesterol (day 25, 15.7%-28.6%) and adiponectin (day 25, 1574 to 3272 ng/mL) across all doses, without significant changes in body weight (day 25, -0.45% to -1.21%). Modest decreases from baseline were observed for N-terminal propeptides of type 1 collagen (P1NP) on day 25, although C-telopeptide cross-linking of type 1 collagen (CTX-1) increased minimally. Systolic, diastolic BP, and pulse rate increased in a dose- and time-related manner. There were 5 serious AEs (one treatment-related) and no deaths. Three participants discontinued because of AEs. The majority of AEs were gastrointestinal. PF-05231023 increased BP and heart rate in rats, but not in monkeys.

CONCLUSIONS

Once-weekly PF-05231023 lowered triglycerides markedly in the absence of weight loss, with modest changes in markers of bone homeostasis. This is the first report showing increases in BP and pulse rate in humans and rats after pharmacological administration of a long-acting FGF21 molecule.

Biopharmaceutical Characterization and Bioavailability Study of a Tetrazole Analog of Clofibric Acid in Rat

In the current investigation, the physicochemical, biopharmaceutical and pharmacokinetic characterization of a new clofibric acid analog (Compound 1) was evaluated. Compound 1 showed affinity by lipophilic phase in 1 to 5 pH interval, indicating that this compound would be absorbed favorably in duodenum or jejunum. Also, Compound 1 possess two ionic species, first above of pH 4.43 and, the second one is present over pH 6.08. The apparent permeability in everted sac rat intestine model was 8.73 × 10-6 cm/s in duodenum and 1.62 × 10-5 cm/s in jejunum, suggesting that Compound 1 has low permeability. Elimination constant after an oral administration of 50 μg/kg in Wistar rat was 1.81 h-1, absorption constant was 3.05 h-1, Cmax was 3.57 μg/mL at 0.33 h, AUC0-α was 956.54 μ/mL·h and distribution volume was 419.4 mL. To IV administration at the same dose, ke was 1.21 h-1, Vd was 399.6 mL and AUC0-α was 747.81 μ/mL·h. No significant differences were observed between pharmacokinetic parameters at every administration route. Bioavailability evaluated was 10.4%. Compound 1 is metabolized to Compound 2 probably by enzymatic hydrolysis, and it showed a half-life of 9.24 h. With these properties, Compound 1 would be considered as a prodrug of Compound 2 with potential as an antidiabetic and anti dyslipidemic agent.

In Silico and Wet Lab Studies Reveal the Cholesterol Lowering Efficacy of Lauric Acid, a Medium Chain Fat of Coconut Oil

The coconut oil (CO) contains 91 % of saturated fatty acids in which 72 % are medium chain fatty acids (MCFAs) like lauric, capric and caprylic acids. In contrast to animal fat, coconut oil has no cholesterol. Despite this fact, CO is sidelined among other vegetable oils due to the health hazards attributed to the saturated fatty acids. Though various medicinal effects of CO have been reported including the hypolipidemic activity, people are still confused in the consumption of this natural oil. In silico analyses and wet lab experiments have been carried out to identify the hypolipidemic properties of MCFAs and phenolic acids in CO by using different protein targets involved in cholesterol synthesis. The molecular docking studies were carried out using CDOCKER protocol in Accelery's Discovery Studio, by taking different proteins like HMG- CoA reductase and cholesterol esterase as targets and the different phytocompounds in coconut as ligands. Molecular docking highlighted the potential of lauric acid in inhibiting the protein targets involved in hyperlipidemics. Further, validation of in silico results was carried out through in vivo studies. The activity of key enzymes HMG- CoA reductase and lipoprotein lipase were found reduced in animals fed with lauric acid and CO.

Evaluation of the impact of 16-dehydropregnenolone on the activity and expression of rat hepatic cytochrome P450 enzymes

16-dehydropregnenolone (DHP) is a promising novel antihyperlipidemic agent developed and patented by Central Drug Research Institute (CDRI), India. The purpose of the present study was to investigate whether DHP influences the activities and mRNA expression of hepatic drug-metabolizing cytochrome P450 (CYP) enzymes (CYP1A2, CYP2C11, CYP2D2, CYP2E1 and CYP3A1) in Sprague-Dawley (SD) rats. A cocktail suspension of CYP probe substrates which contained caffeine (CYP1A2), tolbutamide (CYP2C11), dextromethorphan (CYP2D2), chlorzoxazone (CYP2E1) and dapsone (CYP3A1) was administered orally on eighth- or fifteenth-day to rats pre-treated with DHP intragastrically at a dose of 36 and 72mg/kg for one week and two weeks. The concentrations of probe drugs in plasma were estimated by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Alongside, the effect of DHP on CYPs activity and mRNA expression levels were assayed in isolated rat liver microsomes and by real-time reverse transcription-polymerase chain reaction (RT-PCR), respectively. DHP had significant inducing effects on CYP1A2, 2C11, 2D2 and 2E1 with no effect on CYP3A1 in dose- and time-dependent manner, as revealed from the pharmacokinetic profiles of the probe drugs in rats. In-vitro microsomal activities and mRNA expression results were in good agreement with the in-vivo pharmacokinetic results. Collectively, the results unveiled that DHP is an inducer of rat hepatic CYP enzymes. Hence, intense attention should be paid when DHP is co-administered with drugs metabolized by CYP1A2, 2C11, 2D2 and 2E1, which might result in drug-drug interactions and therapeutic failure.

Effects of phospholipid complexes of total flavonoids from Persimmon (Diospyros kaki L.) leaves on experimental atherosclerosis rats

The total flavonoids from Persimmon leaves (PLF), extracted from the leaves of Diospyros kaki L. Dispryosl and Ebenaceae, is reported to possess many beneficial health effects. However, the oral bioavailability of PLF is relatively low due to its poor solubility. In the present study, the phospholipid complexes of total flavonoids from Persimmon leaves (PLF-PC) was prepared to enhance the oral bioavailability of PLF and to evaluate its antiatherosclerotic properties in atherosclerosis rats in comparison to PLF. A HPLC-MS method was developed and validated for the determination of quercetin and kaempferol in rats plasma to assess the oral bioavailability of PLF-PC. The effect of PLF (50mg/kg/d) and PLF-PC (equivalent to PLF 50mg/kg/d) on atherosclerosis rats induced by excessive administration of vitamin D (600,000IU/kg) and cholesterol (0.5g/kg/d) was assessed after orally administered for 4 weeks. The relative bioavailabilities of quercetin and kaempferol in PLF-PC relative to PLF were 242% and 337%, respectively. The levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), apolipoprotein A1 (ApoA1) and apolipoprotein B (ApoB) in serum were measured by an automatic biochemistry analyzer. The morphological changes of aorta were observed with optical microscopy. According to the levels of biochemical parameters in serum and the morphological changes of aorta, PLF-PC showed better therapeutic efficacy compared to PLF. Thus, PLF-PC holds a promising potential for increasing the oral bioavailability of PLF. Moreover, PLF-PC exerts better therapeutic potential in the treatment of atherosclerotic disease than PLF.

The clinical relevance of omega-3 fatty acids in the management of hypertriglyceridemia

Hypertriglyceridemia (triglycerides > 150 mg/dL) affects ~25 % of the United States (US) population and is associated with increased cardiovascular risk. Severe hypertriglyceridemia (≥ 500 mg/dL) is also a risk factor for pancreatitis. Three omega-3 fatty acid (OM3FA) prescription formulations are approved in the US for the treatment of adults with severe hypertriglyceridemia: (1) OM3FA ethyl esters (OM3EE), a mixture of OM3FA ethyl esters, primarily eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (Lovaza®, Omtryg™, and generics); (2) icosapent ethyl (IPE), EPA ethyl esters (Vascepa®); and (3) omega-3 carboxylic acids (OM3CA), a mixture of OM3FAs in free fatty acid form, primarily EPA, DHA, and docosapentaenoic acid (Epanova®). At approved doses, all formulations substantially reduce triglyceride and very-low-density lipoprotein levels. DHA-containing formulations may also increase low-density lipoprotein cholesterol. However, this is not accompanied by increased non-high-density lipoprotein cholesterol, which is thought to provide a better indication of cardiovascular risk in this patient population. Proposed mechanisms of action of OM3FAs include inhibition of diacylglycerol acyltransferase, increased plasma lipoprotein lipase activity, decreased hepatic lipogenesis, and increased hepatic β-oxidation. OM3CA bioavailability (area under the plasma concentration-time curve from zero to the last measurable concentration) is up to 4-fold greater than that of OM3FA ethyl esters, and unlike ethyl esters, the absorption of OM3CA is not dependent on pancreatic lipase hydrolysis. All three formulations are well tolerated (the most common adverse events are gastrointestinal) and demonstrate a lack of drug-drug interactions with other lipid-lowering drugs, such as statins and fibrates. OM3FAs appear to be an effective treatment option for patients with severe hypertriglyceridemia.

Metabolic Alterations of Toxic and Nonessential Elements by the Treatment of Sempervivum tectorum Extract in a Hyperlipidemic Rat Model

A hyperlipidemic rat model was used to examine the therapeutic effect of Sempervivum tectorum plant extract on the metabolic alterations of Al, As, B, Ba, Cd, Hg, Ni, Pb, and Ti in the liver and bile. Hyperlipidemia was produced by lipogenic diet and alcohol and verified by morphological investigation of the liver with the aid of light and an electron microscope. Element concentration in the liver and bile were determined by inductively coupled plasma optical emission spectrometry (ICP-OES). The concentration values in the liver higher than the detection limit (Al, Ba, Ni, Ti) were unambiguous. Significant differences were found for the four groups at p < 0 .05 level (ANOVA). A significant difference was observed between Al and B concentration in the bile fluids of the 4 groups ( p < 0 .05). The excretion of Al and Ti into the bile fluid increased significantly ( p < 0 .05). Following the administration of S. tectorum extract to rats with hyperlipidemia, the excretion of Al, B and Ba increased, whereas the excretion of Ti decreased significantly ( p < 0 .05). The favorable action of the extract (protecting the liver in hyperlipidemic rats) was verified by morphological studies, and its detoxicating property was shown by the elimination of Al, Ba, Ni, and Ti from the liver.

Lack of an Effect of Ritonavir Alone and Lopinavir-Ritonavir on the Pharmacokinetics of Fenofibric Acid in Healthy Volunteers

STUDY OBJECTIVE

Because we previously observed a significant 41% reduction in gemfibrozil exposure after 2 weeks of lopinavir-ritonavir administration, we sought to determine the influence of lopinavir-ritonavir and ritonavir alone on the pharmacokinetics of fenofibric acid, an alternative to gemfibrozil for the treatment of elevated triglyceride levels.

DESIGN

Open-label, single-sequence pharmacokinetic study.

SETTING

Clinical Research Center at the National Institutes of Health.

SUBJECTS

Thirteen healthy adult volunteers.

INTERVENTION

Subjects received a single oral dose of fenofibrate 145 mg during three study phases: before ritonavir administration, after 2 weeks of administration of ritonavir 100 mg twice/day, and after 2 weeks of administration of lopinavir 400 mg-ritonavir 100 mg twice/day.

MEASUREMENTS AND MAIN RESULTS

Serial blood samples were collected over 120 hours for determination of fenofibric acid concentrations. Fenofibric acid pharmacokinetic parameter values were compared before and after concomitant ritonavir or lopinavir-ritonavir administration. The geometric mean ratios (90% confidence intervals) for fenofibric acid area under the plasma concentration-time curve were 0.89 (0.77-1.01) after 14 days of ritonavir alone compared with baseline (p>0.05) and 0.87 (0.69-1.05) after 14 days of lopinavir-ritonavir compared with baseline (p>0.05). Study drugs were generally well tolerated; all adverse events were mild or moderate, transient, and resolved without intervention.

CONCLUSION

In contrast to a significant interaction between gemfibrozil and lopinavir-ritonavir, neither lopinavir-ritonavir nor ritonavir alone altered the pharmacokinetics of fenofibric acid in healthy volunteers. These data suggest that fenofibrate remains an important option in human immunodeficiency virus-infected patients receiving common ritonavir-boosted therapy.

[Hypolipidemic activity of N-cholinergic antagonist Benzohexonium in the experiments ]

Methods: Experiments were carried out on outbred albino male rats (n = 150, 230-250 g). For modeling dislipoproteinemia (DLP) we used 3 models: single intraperitoneal injection of the detergent triton WR-1339; administration of ethanol; maintenance on a special hypercholesterolaemic diet (HD) during 21 days. Animals were divided into four groups: normal control, model group, gemfibrozil (Gfb) group, benzohexonium (Benz) group. Rats received per os benzohexonium (20mg/kg), reference drug gemfibrozil (50 mg/kg). We determined content of total cholesterol (TCh), triglycerides (TG) in samples of blood serum and liver, TCh in aorta. TCh, TG and Ch-HDL were analyzed spectrophotometrically using of standardized methods. Results: Compared with model group the contents of TCh, TG in serum and liver were significantly decreased in model + Benz group, whereas Ch-HDL was raised in rats fed special HD (P<0.05). Calculated index of atherogenity (TCh - Ch-HDL) / (Ch-HDL) showed the positive effect. Conclusion: The results obtained were shown the hypolipidemic activity of N-cholinergic antagonist Benzohexonium (20 mg/kg) lowered the content of lipids in blood, liver, and aorta.

Development of a LC-MS/MS method for the estimation of clinofibrate in human urine

A highly sensitive and rapid liquid chromatography-tandem mass spectrometry method was developed for the determination of clinofibrate in human urine. The analyte and IS were extracted through a simple protein precipitation by the mixture of acetonitrile and 1 mol/L hydrochloric acid (95:5, v/v) and separated on an Inspire C18 (150 mm x 4.6 mm I.D., 5 μm particle size) column using isocratic elution with methanol and water containing 0.1% formic acid and 10 mM ammonium acetate (90:10, v/v). Mass spectrometric detection was performed in electrospray positive ionization MRM mode. The mass transition was m/z 486.3-->175.0 for clinofibrate and m/z 361.1-->233.1 for IS, respectively. The flow rate was 0.6 mL/min and the column oven temperature was set at 35 °C. The total run time was 6.5 min. Good linear relationships were obtained for all analytes over the concentrations ranging of 0.1002-10.02 μg/mL (r2 = 0.9991) and the limit of quantification was 0.1002 μg/mL. The extraction recovery was larger than 87.4% and intra- and inter-batch precision and accuracy with RSD were all less than 6.5%. The total amount of unchanged clinofibrate excreted in urine was less than 0.34%. This method was successfully applied to the pharmacokinetic study of clinofibrate in human urine.

A metabolomic and pharmacokinetic study on the mechanism underlying the lipid-lowering effect of orally administered berberine

Clinical and animal studies demonstrated that orally administered berberine had a distinct lipid-lowering effect. However, pharmacokinetic studies showed that berberine was poorly absorbed into the body so the levels of berberine in the blood and target tissues were far below the effective concentrations revealed. To probe the underlying mechanism, the effect of berberine on the biological system was studied on a high-fat-diet-induced hamster hyperlipidemia model. Our results showed that intragastrically-administered berberine was poorly absorbed into circulation and most berberine accumulated in gut content. Although the bioavailability of intragastrically administered berberine was much lower than that of intraperitoneally administered berberine, it had a stronger lipid-lowing effect, indicating that the gastrointestinal tract is a potential target for the hypolipidemic effect of berberine. A metabolomic study on both serum and gut content showed that orally administered berberine significantly regulated molecules involved in lipid metabolism, and increased the generation of bile acids in the hyperlipidemic model. DNA analysis revealed that the orally administered berberine modulated the gut microbiota, and berberine showed a significant inhibition of the 7α-dehydroxylation conversion of cholic acid to deoxycholic acid, indicating a decreased elimination of bile acids in the gut. However, in model hamsters, elevated bile acids failed to downregulate the expression and function of CYP7A1 in a negative feedback loop. It was suggested that the hypocholesterolemic effect of orally administered berberine involves modulating the turnover of bile acids and the farnesoid X receptor signal pathway.

The in vitro and in vivo evaluation of fenofibrate with a self- microemulsifying formulation

Fenofibrate is virtually insoluble in water and is highly lipophilic, which leads to poor oral bioavailability. The purpose of this approach is to develop self-microemulsifying drug delivery system (SMEDDS) for oral bioavailability enhancement of fenofibrate. The in vitro dissolution test and pharmacokinetic behavior in beagle dogs were conducted to assess the formulation of fenofibrate in selfmicroemulsifying systems. The concentrations of fenofibrate were determined by HPLC. A crossover fashion study was performed in six fasted beagle dogs with SMEDDS formulation and commercial capsules. The results showed that SMEDDS formulation provides a good drug release with more than 90% of fenofibrate dissoluted from self-emulsifying formulations while less than 10% from the commercial capsules was released within 20min. The mean particle size of SMEDDS formulation after dispersion was about 33.7nm In pharmacokinetic parameters of SMEDDS formulation, the area under the plasma concentration-time curve (AUC) was significantly higher and was approximately 7-fold greater than that obtained when commercial capsule of the same dose of fenofibrate was administered. Also, the maximum absorption was advanced (2h to 1.25h) with SMEDDS formulation. The self-microemulsifying drug delivery systems can significantly increase fenofibrate dissolution in vitro and absorption in vivo.

Comparative pharmacokinetic investigation on baicalin and wogonoside in type 2 diabetic and normal rats after oral administration of traditional Chinese medicine Huanglian Jiedu decoction

ETHNOPHARMACOLOGICAL RELEVANCE

Huanglian Jiedu decoction (HLJDD) is used traditionally in China for the treatment of diabetes mellitus in clinical practice, which has been proved to be effective. The purpose of this study was to investigate the pharmacokinetic characteristics (especially the area under the curve, AUC) of baicalin and wogonoside in type 2 diabetic rats after oral administration of HLJDD extract and to explore its possible mechanism.

MATERIALS AND METHODS

HLJDD extract and Radix scutellariae extract were prepared and the contents of baicalin and wogonoside contained in two extracts were assayed with high performance liquid chromatography (HPLC). Type 2 diabetic rats were induced by high fat diet and intraperitoneal injection of streptozotocin. Pharmacokinetics of baicalin and wogonoside in type 2 diabetic and normal control rats after oral administration of HLJDD extract or Radix scutellariae extract were investigated. Pharmacokinetics of baicalin in type 2 diabetic and normal rats after oral administration of pure baicalin was also investigated.

RESULTS

The pharmacokinetic parameters (especially AUCs) of baicalin and wogonoside in type 2 diabetic rats after oral administration of HLJDD extract were remarkably different from those in normal rats. And the alterations of the AUCs of baicalin and wogonoside in type 2 diabetic rats after oral administration of Radix scutellariae extract were similar to those after oral administration of HLJDD extract. Moreover, the increase of the AUC of baicalin in type 2 diabetic rats after oral administration of pure baicalin was similar to that after oral administration of HLJDD extract or Radix scutellariae extract.

CONCLUSION

The pharmacokinetic behaviors of baicalin and wogonoside (especially the systemic exposure [AUCs] of baicalin and wogonoside) were significantly altered in type 2 diabetic rats after orally administrated HLJDD extract. And the increased AUCs of baicalin and wogonoside in type 2 diabetic rats after oral administration of HLJDD extract resulted from neither the effects of other herbs contained in HLJDD nor the effects of other components contained in Radix scutellariae. It might result from the effects of the pathological status of type 2 diabetes mellitus.

Biopharmaceutical modeling of drug supersaturation during lipid-based formulation digestion considering an absorption sink

PURPOSE

In vitro lipolysis is widely utilized for predicting in vivo performance of oral lipid-based formulations (LBFs). However, evaluation of LBFs in the absence of an absorption sink may have limited in vivo relevance. This study aimed at employing biopharmaceutical modeling to simulate LBF digestion and drug supersaturation in a continuous absorptive environment.

METHODS

Three fenofibrate-loaded LBFs were characterized in vitro (dispersion and lipolysis) and drug precipitation was monitored using in-line Raman spectroscopy. In vitro data were combined with pharmacokinetic data derived from an in vivo study in pigs to simulate intestinal LBF transit. This biopharmaceutical model allowed calculation of lipolysis-triggered drug supersaturation while drug and lipolysis products are absorbed from the intestine.

RESULTS

The biopharmaceutical model predicted that, in a continuous absorption environment, fenofibrate supersaturation was considerably lower compared to in vitro lipolysis (non-sink). Hence, the extensive drug precipitation observed in vitro was predicted to be unlikely in vivo. The absorption of lipolysis products increased drug supersaturation, but drug precipitation was unlikely for highly permeable drugs.

CONCLUSIONS

Biopharmaceutical modeling is a valuable approach for predicting LBFs performance in vivo. In the absence of in vitro tools simulating absorptive conditions, modeling strategies should be further considered.

Bone mineral density in statin users: a population-based analysis from a Spanish cohort

We studied 2,315 subjects (1,422 women and 893 men) from the Camargo Cohort and analyzed the differences in BMD between statin or non-statin users. We also studied effects of the type of statin, dose, pharmacokinetic properties, and length of treatment on bone mineral density (BMD). Of the subjects, 478 (21 %) were taking statins (256 women and 222 men). Overall, they had higher BMD than non-users (p < 0.0001). In adjusted multivariate models, women taking statins had higher BMD at femoral neck (p = 0.002) and total hip (p = 0.04) than non- users. No differences were found in men. Women taking simvastatin had higher increases in BMD than non-statin users at femoral neck (p = 0.02) and total hip (p = 0.009), those taking fluvastatin had lower BMD values at lumbar spine (p = 0.028), and those receiving lovastatin had higher increases at femoral neck (p = 0.006). In men, only atorvastatin was associated with higher femoral neck BMD than non-statin use (p = 0.029). Comparing with non-statin users, only women receiving lipophilic statins had greater BMD at femoral neck (p = 0.003). According to drug potency, women on high- or lower-potency agents showed higher BMD values at femoral neck than non-users (p = 0.028 and 0.022, respectively). In men, only high-potency statins were associated with higher femoral neck BMD than non-use (p = 0.021). No differences between dose or length of statin therapy were noted regarding BMD in either sex. In summary, in a large population-based cohort, women on statins had higher BMD at the hip than non-users. Overall, this increase in BMD was more evident in subjects on lipophilic or high-potency statins.

[Hypoglycemic activity of hypolipidemic preparations]

The system of glucose metabolism regulation is millions of years older than the insilin system and locomotor function. For this reason, the hypoglycemic activity of the hormone is mediated through fatty acid (FA) metabolism. Insulin blocks the ability of mitochondria to oxidize ketone bodies, short-, medium- and long-chain FA and makes them oxidize glucose, i.e. a physiologically unoptimal substrate. The relationship between FA and glucose in the Rnadle cycle is apparent only on the autocrine level (in the cell); they determine alternation of nutritive function (trophology) and biological exo/endo-reactions (after and without feeding respectively). Most antidiabetic medicines exhibit hypoglycemic activity, like insulin; they reduce the level of lipid substrates of oxidation in cytosol and mitochondria have to oxidize glucose. In these conditions, insulin increases glucose uptake by the cells mediated through GLUT4 transporters. Sulfonylurea derivatives enhance secretion of insulin by beta-cell. Biguanides covalently and irreversibly bind ketone bodies thereby preventing their oxidation by mitochondria. Fibrates, glitazones, flavonides, flavones, lipoic thio-FA, endogenous eicosanoids, derivatives of Ω-3 and Ω-6 essential polyenic FA, and conjugated unsaturated FA are agonists of peroxisome proliferator-activated receptors. They stimulate α-, β-, and Ω-oxidation of all exogenous a physiological FA and excessive palmitic saturated FA in peroxisomes which leads to cytosol hypolipidemia. Hypoglycemic preparations with the activity of oxidation beta-blockers arrest FA uptake by mitochondria. Hypoglycemic Ω-3 essential polyenoic FA activate GLUT4 function. Type 2 diabetes in middle-aged patients is a symptom of atherosclerosis, i.e. deficit of essential polyenoic FA caused by disturbed phospholipid synthesis and GLUT4 function. Diabetes should be in the first place considered as pathological FA metabolism and only in the second place as glucose pathology. This inference needs to be taken into account in the treatment of diabetes and in strategic programs of its prophylaxis.

[A fixed-dose lisinopril and amlodipine combination in conjunction with rosuvastatin in patients with hypertensive disease and coronary heart disease]

AIM

To evaluate the efficacy and safety of a fixed-dose combination of the angiotensin-converting enzyme inhibitor lisinopril 10 mg and the calcium antagonist amlodipine 5 mg (ekvator) in conjunction with rosuvastatin (mertenil).

SUBJECTS AND METHODS

The investigation enrolled 50 patients (mean age 57.9 years) with essential hypertension. All the patients received the fixed-dose antihypertensive combination. Stable Functional Class I or II exertional angina was in 46% of the patients. The remaining 54% were found to have brachiocephalic atherosclerosis. All the patients had dyslipidemia and were given rosuvastatin.

RESULTS

The mean systolic blood pressure (SBP) initially reached 164.26 mm Hg. During the whole follow-up, the reduction in mean SBP generally accounted for 22.6% (p = 0.000). At the study inclusion, the mean diastolic blood pressure (DBP) reached 99.38 mm Hg. The total decline in mean DBP was 19.3% (p = 0.000). The mean level of total cholesterol (TC) decreased significantly by 32.1% (p = 0.000); that of triglycerides (TG) also fell significantly by 31.8% (p = 0.04); that of high-density lipoproteins increased insignificantly by 11.1% (p = 0.599); that of low-density lipoproteins (LDL) dropped significantly by 47.5% (p = 0.000).

CONCLUSION

Being safe, the fixed-dose lisinopril and amlodipine combination is effective in lowering blood pressure in patients with hypertensive disease (HD) concurrent with coronary heart disease (CHD) or atherosclerotic changes in the carotid artery. The use of rosuvastatin in patients with HD concurrent with CHD during 2 months causes positive changes in the blood lipid composition as a significant reduction in the-levels of (TC), LDL, and TG.

GSK256073, a selective agonist of G-protein coupled receptor 109A (GPR109A) reduces serum glucose in subjects with type 2 diabetes mellitus

AIMS

This clinical trial assessed whether a potent, selective GPR109A agonist, GSK256073, could, through inhibition of lipolysis, acutely improve glucose homeostasis in subjects with type 2 diabetes mellitus.

METHODS

Thirty-nine diabetic subjects were enrolled in the randomized, single-blind, placebo-controlled, three-period crossover trial. Each subject received placebo and two of four regimens of GSK256073 for 2 days. GSK256073 was dosed 5 mg every 12 h before breakfast and supper (BID), 10 mg every 24 h before breakfast (QD), 25 mg BID and 50 mg QD.

RESULTS

The change from baseline weighted mean glucose concentration for an interval from 24 to 48 h after the initial drug dose was significantly reduced for all GSK256073 regimens, reaching a maximum of -0.87 mmol/l (-1.20, -0.52) with the 25 mg BID dose. Sustained suppression of non-esterified fatty acid (NEFA) and glycerol concentrations was observed with all GSK256073 doses throughout the 48-h dosing period. Serum insulin and C-peptide concentrations fell in concert with glucose concentrations and calculated HOMA-IR scores decreased 27-47%, consistent with insulin sensitization. No marked differences were evident between either 10 and 50 mg total daily doses or QD versus BID dosing.

CONCLUSIONS

Administration of a GPR109A agonist for 2 days significantly decreased serum NEFA and glucose concentrations in diabetic subjects. Glucose improvements were associated with decreased insulin concentrations and measures of enhanced insulin sensitivity. Improved glucose control occurred with GSK256073 doses that were generally safe and not associated with events of flushing or gastrointestinal disturbances.

Liraglutide suppresses postprandial triglyceride and apolipoprotein B48 elevations after a fat-rich meal in patients with type 2 diabetes: a randomized, double-blind, placebo-controlled, cross-over trial

AIMS

Postprandial triglyceridaemia is a risk factor for cardiovascular disease (CVD). This study investigated the effects of steady-state liraglutide 1.8 mg versus placebo on postprandial plasma lipid concentrations after 3 weeks of treatment in patients with type 2 diabetes mellitus (T2DM).

METHODS

In a cross-over trial, patients with T2DM (n = 20, 18-75 years, BMI 18.5-40 kg/m²) were randomized to once-daily subcutaneous liraglutide (weekly dose escalation from 0.6 to 1.8 mg) and placebo. After each 3-week period, a standardized fat-rich meal was provided, and the effects of liraglutide on triglyceride (primary endpoint AUC(0-8h)), apolipoprotein B48, non-esterified fatty acids, glycaemic responses and gastric emptying were assessed. ClinicalTrials.gov ID: NCT00993304.

FUNDING

Novo Nordisk A/S.

RESULTS

After 3 weeks, mean postprandial triglyceride (AUC(0-8h) liraglutide/placebo treatment-ratio 0.72, 95% CI [0.62-0.83], p = 0.0004) and apolipoprotein B48 (AUC(0-8h) ratio 0.65 [0.58-0.73], p < 0.0001) significantly decreased with liraglutide 1.8 mg versus placebo, as did iAUC(0-8h) and C(max) (p < 0.001). No significant treatment differences were observed for non-esterified fatty acids. Mean postprandial glucose and glucagon AUC(0-8h) and C(max) were significantly reduced with liraglutide versus placebo. Postprandial gastric emptying rate [assessed by paracetamol absorption (liquid phase) and the ¹³C-octanoate breath test (solid phase)] displayed no treatment differences. Mean low-density lipoprotein and total cholesterol decreased significantly with liraglutide versus placebo.

CONCLUSIONS

Liraglutide treatment in patients with T2DM significantly reduced postprandial excursions of triglyceride and apolipoprotein B48 after a fat-rich meal, independently of gastric emptying. Results indicate liraglutide's potential to reduce CVD risk via improvement of postprandial lipaemia.

Metabolism of fenofibrate in beagle dogs: new metabolites identified and metabolic pathways revealed

Fenofibrate is a prototypical agonist of peroxisome proliferator-activated receptor alpha (PPARalpha) which is well known to be associated with species related carcinogenesis. Important species differences have been reported in its metabolism and elimination pattern. Its new metabolites have been revealed in Cynomolgus monkeys and Sprague-Dawley rats. However in beagle dogs, several polar metabolites of fenofibrate have not been identified yet. In this study, beagle dogs were orally dosed with fenofibrate mixed with feeds. Urine and plasma samples were collected and subject to LC-MS/MS by comparison with authentic compounds and confirmed using an API 4000 Q-TRAP system. In vitro cultured primary hepatocytes were used to reveal metabolic pathways and confirm the data in vivo. Seven new metabolites of fenofibrate in dogs were identified, and their metabolic pathways were revealed. Fenofibrate in beagle dogs was found to be more prone to be metabolized into other secondary metabolites than fenofibric acid, compared with that in rats.

Monocyte-suppressing effects of simvastatin in patients with isolated hypertriglyceridemia

BACKGROUND

No previous study investigated statin action on monocyte cytokine release and systemic inflammation in patients with isolated hypertriglyceridemia.

METHODS

Our study included 43 subjects with isolated hypertriglyceridemia and peripheral artery stenosis randomly allocated to one of two groups, treated for 12 weeks with either simvastatin (40 mg twice daily) or placebo. Plasma lipids, glucose homeostasis markers, plasma C-reactive protein and monocyte cytokine release were determined on the day of allocation and at the end of the treatment period.

RESULTS

Simvastatin, but not placebo, reduced monocyte release of tumor necrosis factor-α, interleukin-6, interleukin-1β and monocyte chemoattractant protein-1, as well decreased plasma levels of C-reactive protein.

CONCLUSIONS

Our study shows that simvastatin reduces monocyte secretory function and has systemic anti-inflammatory properties in patients with isolated hypertriglyceridemia.

[Experience with simvastatin therapy for the achievement of osteoprotective effects in women with hyperlipidemia]

The aim of the work was to study the influence of statins on the functional and metabolic state of bone tissue during correction of type IIA and IIB hyperlipidemia in women with osteopenia. 53 of the 83 patients aged 45-50 years were treated with statins (20 mg/d) and low-fat diet. Bone mineral density (BMD) was measured in the lumbar spine region (LII-LIV) and femoral neck by DEXA. Simultaneously the lipid profile and serum bone metabolism markers (osteocalcin, beta-CrossLaps CL) were detected. Simvastatin therapy led to normalization of osteocalcin level (p<0.01) within 6 months. In the control group, it remained unaltered and tended to decrease after 12 months (p>0.05). The level of bone resorption marker (CL) dropped within 3 months after the onset of therapy (p<0.050) and continued to decrease by the 12th month (p<0.05). It was significantly lower than in controls (p<0.05) both after 6 and 12 months. BMD in the femoral neck and LII-LIV increased by 2.2 and 2.6% respectively after 12 months of simvastatin therapy and by 1.4 and 1.7% after consumption of low-fat diet. It is concluded that simvaststin therapy (20 mg/d) during 12 months has positive effect on bone metabolism during treatment of atherogenic hyperlipidemia in patients with osteopenia.

HDL-cholesterol: perfection is the enemy of good?

An inverse relationship between the plasma concentration of high-density lipoprotein (HDL)-cholesterol and the risk of having a cardiovascular event has been shown in several epidemiologic studies. It is likely that this relationship is causal because HDL has several intrinsic properties that can potentially reverse atherosclerosis. However, this has not been conclusively shown in humans, and trying to achieve perfection with pharmacotherapy is possibly the enemy of good (ie, a healthy lifestyle). Patients with low HDL should be advised to change their lifestyle, including smoking cessation, weight reduction, and regular exercise.

Novel developments in omega-3 fatty acid-based strategies

PURPOSE OF REVIEW

Omega-3 polyunsaturated fatty acids (n-3 PUFAs) have been attributed with several health benefits, including triglyceride lowering and cardiovascular disease risk reduction. This review focuses on new prescription omega-3 fatty acid products in development and recently published data regarding omega-3 fatty acid effects on arrhythmias, heart failure, and platelet inactivation.

RECENT FINDINGS

A free fatty acid form of n-3 PUFA was found to produce a four-fold higher area under the plasma n-3 PUFA curve than prescription omega-3-acid ethyl esters in patients on a low-fat diet. Eicosapentaenoic acid ethyl esters reduced triglyceride without significantly elevating LDL cholesterol in patients with severe hypertriglyceridemia and in those with mixed dyslipidemia. Recent investigations of n-3 PUFA effects on ventricular and atrial arrhythmias, including studies in patients with implanted defibrillators, failed to demonstrate a significant benefit. However, increased fatty fish or n-3 PUFA consumption was associated with a lower rate of hospitalization in heart failure patients. A further important finding was potentiation of the antiplatelet response when n-3 PUFAs were added to aspirin + clopidogrel.

SUMMARY

Although n-3 PUFA therapy continues to show promise in the prevention and management of cardiovascular diseases, further research is necessary to more fully elucidate its role in specific disorders.

IVIVR in oral absorption for fenofibrate immediate release tablets using dissolution and dissolution permeation methods

In a previous study it has been demonstrated that a dissolution/permeation (D/P) system can discriminate between different immediate release fenofibrate formulations. The fractions permeated were correlated with fenofibrate's in vivo exposure in rats following p.o. administration. In the present study more detailed investigations are presented using data from six fenofibrate tablets tested in vivo in humans. In these pharmacokinetic studies no significant differences between formulations in AUC but in Cmax were found. Differences between the Cmax values were not explained by the dissolution characteristics of the tablets but were rationalized on the basis of micellar entrapment and diminished mobility of the active ingredient by surfactants in the formulations. This was demonstrated by a permeation system using dialysis membranes. Thus a permeation step in addition to dissolution measurement may significantly improve the establishment of an IVIV relationship.

[Association of a polymorphic marker Trp719Arg of KIF6 gene with effects of atorvastatin and simvastatin in patients with early ischemic heart disease]

Action of statins is characterized by pronounced variability what is caused by effects of a multitude of factors. Main of these factors appears to be genetic peculiarity of patients. We studied influence of polymorphic marker Trp719Arg of KIF6 gene on lipid and nonlipid effects of atorvastatin and simvastatin. The studied genetic marker is associated with risk of development of ischemic heart disease and myocardial infarction as well as efficacy of therapy with statins according to data of a number of large multicenter studies. We examined 60 men with ischemic heart disease which had manifested in young age when genetic factors were most expressed and had special significance. Efficacy of 40 mg/day simvastatin did not depend on genotypes of polymorphic marker Trp719Arg of KIF6. Therapy with 10 mg/day atorvastatin was more effective in carriers of polymorphic marker Trp719Arg of KIF6 gene by action on dynamics of changes of high sensitivity C-reactive protein and dispersion of high density lipoprotein response. Increase of atorvastatin dose to 80 mg/day abolished influence of genotypes. Thus for the first time we discovered influence of polymorphic marker Trp719Arg of KIF6 gene on individual response to therapy with 10 mg/day of atorvastatin, while and apoA1, structural protein of high density lipoproteins can be considered as a marker of "fast response".

IVIVR in oral absorption for fenofibrate immediate release tablets using dissolution and dissolution permeation methods

In a previous study it has been demonstrated that a dissolution/permeation (D/P) system can discriminate between different immediate release fenofibrate formulations. The fractions permeated were correlated with fenofibrate's in vivo exposure in rats following p.o. administration. In the present study more detailed investigations are presented using data from six fenofibrate tablets tested in vivo in humans. In these pharmacokinetic studies no significant differences between formulations in AUC but in Cmax were found. Differences between the Cmax values were not explained by the dissolution characteristics of the tablets but were rationalized on the basis of micellar entrapment and diminished mobility of the active ingredient by surfactants in the formulations. This was demonstrated by a permeation system using dialysis membranes. Thus a permeation step in addition to dissolution measurement may significantly improve the establishment of an IVIV relationship.

Effect of medication burden on persistent use of lipid-lowering drugs among patients with hypertension

OBJECTIVE

To determine the effect of medication burden on persistent use of newly added lipid-lowering (LL) drugs among patients with hypertension.

STUDY DESIGN

This retrospective database study used medical and pharmacy claims from a mid-Atlantic managed care organization. The cohort was obtained from continuous member enrollment in pharmacy and medical benefits from January 1, 2003, to December 31, 2005.

METHODS

Prescription claims were obtained for 18 months following the date of the first filled LL prescription (ie, index date). Patients were stratified into patients who changed LL drug or strength (group 1) and patients who did not change LL drug or strength (group 2). The primary outcome measure was persistence to newly added LL therapy. Persistence was defined by the length of time a member remained on therapy following the index date. The secondary outcome measure was the medication possession ratio (MPR). The MPR was calculated as the ratio of the sum of the days' supply of prescription filled divided by the number of days filled, plus the days' supply for the final prescription fill. Associations between the daily medication burden, defined as the number of unique drug products, and the outcome measures were analyzed.

RESULTS

In the cohort of 3058 patients, the mean medication burden was 2.9 medications. Medication burden was positively associated with persistence and MPR through 18 months. Patients who had greater medication burden had longer persistence (P <.001). Likewise, patients who had greater medication burden had higher MPRs and were more likely to be considered adherent (MPR, >80%) (P < .001 for both).

CONCLUSIONS

Patients with higher medication burden had greater adherence to newly added LL therapy. Medication burden should not deter clinicians from adding LL therapy. Among patients with added LL therapy, more attention should focus on patients who have changes to their LL regimen compared with patients who continue on the same LL prescription.

A study of the pharmacokinetic interactions of the direct renin inhibitor aliskiren with metformin, pioglitazone and fenofibrate in healthy subjects

OBJECTIVE

Hypertension and type 2 diabetes are common comorbidities, thus many patients receiving antihypertensive medication require concomitant therapy with hypoglycemic or lipid-lowering drugs. The aim of these three studies was to investigate the pharmacokinetics, safety and tolerability of aliskiren, a direct renin inhibitor for the treatment of hypertension, co-administered with the glucose-lowering agents metformin or pioglitazone or the lipid-lowering agent fenofibrate in healthy volunteers.

METHODS

In three open-label, multiple-dose studies, healthy volunteers (ages 18 to 45 years) received once-daily treatment with either metformin 1000 mg (n = 22), pioglitazone 45 mg (n = 30) or fenofibrate 200 mg (n = 21) and aliskiren 300 mg, administered alone or co-administered in a two-period study design. Blood samples were taken frequently on the last day of each treatment period to determine plasma drug concentrations.

RESULTS

Co-administration of aliskiren with metformin decreased aliskiren area under the plasma concentration- time curve during the dose interval (AUC(tau)) by 27% (geometric mean ratio [GMR] 0.73; 90% confidence interval [CI] 0.64, 0.84) and maximum observed plasma concentration (C(max)) by 29% (GMR 0.71; 90% CI 0.56, 0.89) but these changes were not considered clinically relevant. Co-administration of aliskiren with fenofibrate had no effect on aliskiren AUC (GMR 1.05; 90% CI 0.96, 1.16) or C(max) (GMR 1.05; 90% CI 0.80, 1.38); similarly, co-administration of aliskiren with pioglitazone had no effect on aliskiren AUC(tau) (GMR 1.05; 90% CI 0.98, 1.13) or C(max) (GMR 1.01; 90% CI 0.84, 1.20). All other AUC and C(max) GMRs for aliskiren, metformin, pioglitazone, ketopioglitazone, hydroxypioglita-zone and fenofibrate were close to unity and the 90% CI were contained within the bioequivalence range of 0.80 to 1.25.

CONCLUSION

Co-administration of aliskiren with metformin, pioglitazone or fenofibrate had no significant effect on the pharmacokinetics of these drugs in healthy volunteers. These findings indicate that aliskiren can be co-administered with metformin, pioglitazone or fenofibrate without the need for dose adjustment.

Preformulative assessment of preformed complexes of gemfibrozil, with cyclodextrins

The aim of this study is to carry out preformulative investigations on preformed inclusion complexes of the poorly water-soluble, lipid-lowering agent gemfibrozil and naturally occurring cyclodextrins (CDs). Phase solubility studies showed a linear AL- type diagram with alpha, beta, and y cyclodextrins, indicating the formation of inclusion complexes in a 1:1 molar ratio with all the three CDs. beta-CD-gemfibrozil complex having a maximum stability constant of 148.88 M(-1) was selected for preparation of preformed inclusion complex by kneading, co-precipitation, co-evaporation, and freeze-drying and compared with the physical mixture. The kneaded product was subjected to microwave-drying, with this mode of drying studied as an alternative method for preparation of the complex. The prepared complexes were assessed by equilibrium solubility analysis and intrinsic dissolution rate studies. Further characterization was done by differential scanning calorimetry, X-ray powder diffractometry, Fourier transform infrared spectroscopy, and scanning electron microscopy. The freeze-dried product was identified as the inclusion complex having the maximum intrinsic dissolution rate and hence was assessed for changes in permeability characteristics. pH partition studies and partial in vivo permeability studies showed no changes in the permeability of the freeze-dried product when compared to the pure drug.

Multiple Inhibition Mechanisms and Prediction of Drug–Drug Interactions: Status of Metabolism and Transporter Models as Exemplified by Gemfibrozil–Drug Interactions

PURPOSE

To assess the consequences of multiple inhibitors and differential inhibition mechanisms on the prediction of 12 gemfibrozil drug-drug interactions (DDIs). In addition, qualitative zoning of transporter-related gemfibrozil and cyclosporine DDIs was investigated.

METHODS

The effect of gemfibrozil and its acyl-glucuronide on different enzymes was incorporated into a metabolic prediction model. The impact of CYP2C8 time-dependent inhibition by gemfibrozil acyl-glucuronide was assessed using repaglinide, cerivastatin, loperamide, rosiglitazone and pioglitazone DDIs. Gemfibrozil and cyclosporine inhibition data obtained in human embryonic kidney cells expressing OATP1B1 and hepatic input concentration ([I]in) were used for qualitative zoning of 14 transporter-mediated DDIs.

RESULTS

Incorporation of time-dependent inhibition by gemfibrozil glucuronide showed no significant improvement in the prediction, as CYP2C8 contributed <65% to the overall elimination of the victim drugs investigated. Qualitative zoning of OATP1B1 DDIs resulted in no false negative predictions; yet the magnitude of observed interactions was significantly over-predicted.

CONCLUSIONS

Time-dependent inhibition by gemfibrozil glucuronide is only important for victim drugs eliminated predominantly (>80%) via CYP2C8. Qualitative zoning of OATP1B1 inhibitors based on [I]in/K (i) is valid in drug screening to avoid false negatives. Refinement of the transporter model by incorporating the fraction of drug transported by a particular transporter is recommended.

Pharmacokinetic properties of crocin (crocetin digentiobiose ester) following oral administration in rats

This study investigated the pharmacokinetic properties of crocin following oral administration in rats. After a single oral dose, crocin was undetected while crocetin, a metabolite of crocin, was found in plasma at low concentrations. Simultaneously, crocin was largely present in feces and intestinal contents within 24h. After repeated oral doses for 6 days, crocin remained undetected in plasma and plasma crocetin concentrations were comparable to the corresponding data obtained after the single oral dose. Furthermore, the absorption characteristics of crocin were evaluated in situ using an intestinal recirculation perfusion method. During recirculation, crocin was undetected and low concentrations of crocetin were detected in plasma. The concentrations of crocin in the perfusate were reduced through different intestinal segments, and the quantities of drug lost were greater throughout the colon. These results indicate that (1) orally administered crocin is not absorbed either after a single dose or repeated doses, (2) crocin is excreted largely through the intestinal tract following oral administration, (3) plasma crocetin concentrations do not tend to accumulate with repeated oral doses of crocin, and (4) the intestinal tract serves as an important site for crocin hydrolysis.