Modulation of platelet activation and thrombus formation using a pan-PI3K inhibitor S14161

The phosphatidylinositol 3–kinase (PI3K) signaling pathway is critical in modulating platelet functions. In the present study, we evaluated the effect of S14161, a recently identified pan-class I PI3K inhibitor, on platelet activation and thrombus formation. Results showed that S14161 inhibited human platelet aggregation induced by collagen, thrombin, U46619, and ADP in a dose-dependent manner. Flow cytometric studies showed that S14161 inhibited convulxin- or thrombin-induced P-selectin expression and fibrinogen binding of single platelet. S14161 also inhibited platelet spreading on fibrinogen and clot retraction, processes mediated by outside-in signaling. Using a microfluidic chamber we demonstrated that S14161 decreased platelet adhesion on collagen-coated surface by about 80%. Western blot showed that S14161 inhibited phosphorylation of Akt at both Ser473 and Thr308 sites, and GSK3β at Ser9 in response to collagen, thrombin, or U46619. Comparable studies showed that S14161 has a higher potential bioavailability than LY294002, a prototypical inhibitor of pan-class I PI3K. Finally, the effects of S14161 on thrombus formation in vivo were measured using a ferric chloride-induced carotid artery injury model in mice. The intraperitoneal injection of S14161 (2 mg/kg) to male C57BL/6 mice significantly extended the first occlusion time (5.05±0.99 min, n = 9) compared to the vehicle controls (3.72±0.95 min, n = 8) (P<0.05), but did not prolong the bleeding time (P>0.05). Taken together, our data showed that S14161 inhibits platelet activation and thrombus formation without significant bleeding tendency and toxicity, and considering its potential higher bioavailability, it may be developed as a novel therapeutic agent for the prevention of thrombotic disorders.

Efficacy and safety of nebivolol and valsartan as fixed-dose combination in hypertension: a randomised, multicentre study

BACKGROUND

The fixed-dose combination of any two antihypertensive drugs from different drug classes is typically more effective in reducing blood pressure than a dose increase of component monotherapy. We assessed the efficacy and safety of a fixed-dose combination of a vasodilating β blocker (nebivolol) and an angiotensin II receptor blocker (valsartan) in adults with hypertension.

METHODS

We did an 8-week, phase 3, multicentre, randomised, double-blind, placebo-controlled, parallel-group trial at 401 US sites. Participants (age ≥18 years) with hypertension but with blood pressure less than 180/110 mm Hg were randomly assigned (2:2:2:2:2:2:2:1) by a 24-h interactive web response system in blocks of 15 to 4 weeks of double-blind treatment with nebivolol and valsartan fixed-dose combination (5 and 80 mg/day, 5 and 160 mg/day, or 10 and 160 mg/day), nebivolol (5 mg/day or 20 mg/day), valsartan (80 mg/day or 160 mg/day), or placebo. Doses were doubled in weeks 5-8; results are reported according to the final dose. Participants and research staff were masked to treatment allocation. The primary and key secondary endpoints were changes from baseline to week 8 in diastolic and systolic blood pressure, respectively. The primary statistical comparison was between the highest fixed-dose combination dose and the highest monotherapy doses; lower doses were then compared if this comparison was positive (Hochberg method for multiple testing). Efficacy analyses were by intention to treat. Safety assessments included monitoring of adverse events. Continuous efficacy parameters were analysed using an ANCOVA model; binary outcomes were analysed using a logistic regression model. This study is registered with ClinicalTrials.gov, NCT01508026.

FINDINGS

Between Jan 6, 2012, and March 15, 2013, 4161 patients were randomly assigned (277 to placebo and 554-555 to each active comparator group), 4118 of whom were included in the primary analysis. At week 8, the fixed-dose combination 20 and 320 mg/day group had significantly greater reductions in diastolic blood pressure from baseline than both nebivolol 40 mg/day (least-squares mean difference -1·2 mm Hg, 95% CI -2·3 to -0·1; p=0·030) and valsartan 320 mg/day (-4·4 mm Hg, -5·4 to -3·3; p<0·0001); all other comparisons were also significant, favouring the fixed-dose combinations (all p<0·0001). All systolic blood pressure comparisons were also significant (all p<0·01). At least one treatment-emergent adverse event was experienced by 30-36% of participants in each group.

INTERPRETATION

Nebivolol and valsartan fixed-dose combination is an effective and well-tolerated treatment option for patients with hypertension.

FUNDING

Forest Research Institute.

The effect of nebivolol on P wave duration and dispersion in patients with Behçet's disease; a prospective single-arm controlled study

OBJECTIVE

Behçet's disease (BD) is a chronic multi-system disease presenting with recurrent oral and genital ulceration, and relapsing uveitis. Left ventricular diastolic dysfunction, ventricular arrhythmia and sudden cardiac death have been documented in BD. P wave dispersion (PD) has been reported to be associated with inhomogeneous and discontinuous propagation of sinus impulses. PD has been reported to be longer in patients with BD. Nebivolol, besides its selective beta1-blocking activity, causes an endothelium dependent vasodilatation through nitric oxide release. In this study, we searched for the effects of nebivolol on P wave duration and dispersion in patients with BD.

METHODS

This study was designed as prospective single-arm controlled study. We prospectively studied 35 Behçet's patients who were diagnosed according to the International Study Group criteria. Patients received 5 mg nebivolol per day for 3 months. The patients were evaluated with 12-leads electrocardiography at baseline and after for 3-month therapy. The difference between maximum and minimum P wave durations was defined as PD. The paired samples t test, Wilcoxon test were used for statistical analysis.

RESULTS

A significant decrease was observed in PD after therapy period (62.85±21.62 vs. 44.28±18.03 msec, p=0.001). No adverse effects were observed in treatment period.

CONCLUSION

BD is associated with prolonged P wave duration and dispersion. We have shown for the first time that nebivolol causes a significant decrease in maximum P wave duration and PD in patients with BD. However, further comprehensive studies are needed to determine the long-term effects of nebivolol.

Sargachromenol from Sargassum micracanthum inhibits the lipopolysaccharide-induced production of inflammatory mediators in RAW 264.7 macrophages

During our ongoing screening program designed to determine the anti-inflammatory potential of natural compounds, we isolated sargachromenol from Sargassum micracanthum. In the present study, we investigated the anti-inflammatory effects of sargachromenol on lipopolysaccharide (LPS)-induced inflammation in murine RAW 264.7 macrophage cells and the underlying mechanisms. Sargachromenol significantly inhibited the LPS-induced production of nitric oxide (NO) and prostaglandin E₂ (PGE₂) in a dose-dependent manner. It also significantly inhibited the protein expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) in a dose-dependent manner in LPS-stimulated macrophage cells. Further analyses showed that sargachromenol decreased the cytoplasmic loss of inhibitor κBα (IκBα) protein. These results suggest that sargachromenol may exert its anti-inflammatory effects on LPS-stimulated macrophage cells by inhibiting the activation of the NF-κB signaling pathway. In conclusion, to our knowledge, this is the first study to show that sargachromenol isolated from S. micracanthum has an effective anti-inflammatory activity. Therefore, sargachromenol might be useful for cosmetic, food, or medical applications requiring anti-inflammatory properties.

Effects of nebivolol on liver fibrosis induced by bile duct ligation in Wistar rats

AIM

To study the effect of nebivolol on liver fibrosis induced by common bile duct ligation (BDL) in rats.

MATERIALS AND METHODS

After BDL, Wistar rats were divided into three groups (n=24): SO, sham-operated animals; BDL, BDL rats without treatment; BDL+N, BDL rats treated with nebivolol for five weeks. Alanine aminotransferase, aspartate aminotransferase, gamma glutamyltransferase, total bilirubin and albumin levels were assessed. Liver samples collected were stained with hematoxylin-eosin, Masson's trichrom and reticulin.

RESULTS

Mortality reached 37.5% in the BDL group, whereas no deaths were observed in the SO and BDL+N groups. The BDL group showed hepatic damage as evidenced by elevation in serum biochemical parameters and fibrosis scores. These pathophysiological changes were attenuated in the BDL+N group. However, there was no significant difference between these two groups.

CONCLUSION

Nebivolol improved the survival rate of animals with BDL, but was unable to significantly improve liver function or reduce liver fibrosis.

[Inhibition of Bcl-2 stimulates neuronal stem proliferation in organotypic cultures of mice hippocampus]

In the current study, we investigated the participation of Bcl-2 in both processes of hippocampus neuronal stem cells (NSC) proliferation and differentiation. Present experiments are performed on organotypic cultures of mice hippocampus. A selective inhibitor Bcl-2 HA14-1 (10 μM) is supplied in incubating medium and the concentration is maintained at a constant level. Our data demonstrate that per cent of surviving cells is significantly higher in the group with the supplement HA14-1 then in the control group. In additional, expressions both phospho-histone H3 and Oct3/4 significantly increase in the group with supplement HA14-1. The facts suggest about activation of NSCs proliferation. After 6 weeks incubation, formation of embryoid bodies is observed in the group with HA14-1, that also suggest about NSCs proliferation, but not their differentiation. Also we estimate the level of NSCs differentiation. Our data have shown that the level of CRMP-2 (a protein which participates in axon growth during NSCs differentiation) decreases in the group with HA14-1. We also estimate level of ERK1/2 kinase activity of the MAPK signaling pathway, which immediately regulates neuronal differentiation. Decreasing of both activities ERK1/2 and CRMP-2 indicates diminution of neuronal differentiation in the experimental group. Thus, we demonstrate that inhibition of Bcl-2 increasingly stimulates NSCs proliferation, so that, it suggests that Bcl-2 controls NSCs differentiation to neurons.

Hypotriglyceridemic potential of fermented mixed tea made with third-crop green tea leaves and camellia (Camellia japonica) leaves in Sprague-Dawley rats

Fermented mixed tea made with third-crop green tea leaves and camellia leaves by a tea-rolling process has been developed. The objective of this study was to investigate hypotriglyceridemic potential of the mixed tea in rats. The mixed tea contained theasinensins and theaflavins. Rats fed the mixed tea extract at the level of 1% exerted significantly lower body weight and adipose tissue weight compared to animals fed third-crop green tea or camellia tea extract alone for 4 weeks. Serum and hepatic triglyceride was significantly and dose-dependently decreased by the mixed tea. This decrease was associated with lowered lipogenic enzyme activities in the liver. Furthermore, an oral administration of 4 or 8% of the mixed tea extract followed by fat emulsion suppressed the increment of serum triglyceride level. These results suggest that the mixed tea has hypotriglyceridemic action, partially via delaying triglyceride absorption in the small intestine and repressing hepatic lipogenic enzymes.

Enhanced transdermal drug delivery of zaltoprofen using a novel formulation

Zaltoprofen is a non-steroidal anti-inflammatory drug (NSAID) belonging to the propionic acid class. It has strong inhibitory effects on acute and chronic inflammation. Although zaltoprofen is well tolerated orally compared to other NSAIDs, it has to be administered in three to four doses per day and was associated with ulcerogenicity, bellyache and indigestion. This makes administration of zaltoprofen unsuitable for patients with gastric ulcer and is also associated with drug interactions. Therefore, it is important to develop an alternative dosage form which is easier to administer and avoids first-pass metabolism. The transdermal route meets all the above advantages. In this study, zaltoprofen gels were prepared using carbomer with mixture solution of polyethylene glycol (PEG) 400, Tween 80 and (2-hydroxypropyl)-β-cyclodextrin (HPCD) (called as T2), subsequently oleic acid as a penetration enhancer was added. Zaltoprofen gel containing T2 and oleic acid could promote the percutaneous absorption of zaltoprofen and increase AUC by 183% compared to zaltoprofen gel without T2 and oleic acid. Also, there was a finding zaltoprofen gel containing T2 and oleic acid did not cause dermal irritations in an experimental animal.

Placebo effect and efficacy of nebivolol in patients with hypertension not controlled with lisinopril or losartan: a phase IV, randomized, placebo-controlled trial

BACKGROUND

Most patients with hypertension require more than one antihypertensive to achieve blood pressure (BP) control.

OBJECTIVE

The purpose of this trial was to assess the efficacy and tolerability of add-on nebivolol, a vasodilatory β-blocker, in patients with untreated or poorly controlled hypertension, receiving stable therapy with lisinopril (an angiotensin-converting enzyme inhibitor) or losartan (an angiotensin II receptor blocker).

STUDY DESIGN

This was a phase IV double-blind, placebo-controlled trial conducted from August 2008 to March 2010 (ClinicalTrials.gov identifier: NCT00734630). Patients entered a 2-week, single-blind, placebo-only washout phase, followed by a 3- to 4-week open-label lead-in phase (lisinopril, 10-20 mg/day, or losartan, 50-100 mg/day), and a 12-week randomized, double-blind add-on treatment phase with placebo or nebivolol (5-40 mg/day).

SETTING

This study was conducted at 76 outpatient centers in the United States.

PATIENTS

Participants were men and women aged 18-85 years with a diagnosis of primary hypertension and seated trough systolic BP (SBP) at screening in the range of 170-200 mmHg if untreated, 155-180 mmHg if taking 1 antihypertensive medication, or 140-170 mmHg if taking 2 antihypertensive medications.

INTERVENTION

The intervention was 12 weeks' treatment with nebivolol 5-40 mg/day added to a background therapy of lisinopril 10-20 mg/day or losartan 50-100 mg/day.

MAIN OUTCOME MEASURES

Primary and secondary efficacy parameters were changes from baseline in seated trough cuff SBP and diastolic BP (DBP) at Week 12, respectively. Tolerability was assessed by monitoring treatment-emergent adverse events (TEAEs).

RESULTS

A total of 491 patients were randomized to receive nebivolol (n=258) or placebo (n=233). Efficacy analyses were conducted for 256 nebivolol and 232 placebo patients (intent-to-treat population); completion rates were 88.8% and 85.8%, respectively. Mean baseline SBP/DBP values were 163.1/98.2 mmHg (nebivolol) and 162.4/96.8 mmHg (placebo). Nebivolol was associated with a non-significant mean±SD reduction in SBP (-10.1±16.9 mmHg) versus placebo (-7.3±15.9 mmHg, P=0.093) and significant mean DBP reduction (-7.8±10.1 mmHg vs -3.5±10.6 mmHg, P<0.001). Subgroup analysis suggested a significant effect on DBP for patients receiving background losartan treatment (-8.1±9.2 mmHg vs -3.1±9.4 mmHg, P<0.001), but not for those receiving lisinopril (-7.6±10.8 mmHg vs -3.8±11.6 mmHg, P=0.076). A total of 28% nebivolol-treated and 22% placebo-treated patients reported a TEAE, the most frequent being upper respiratory tract infection (4.3% and 2.1%, respectively), bradycardia (2.7% and 0%), headache (2.3% and 2.1%), and nasopharyngitis (2.3% and 0.9%).

CONCLUSION

These data suggest that nebivolol, when added to lisinopril or losartan, results in an additional BP reduction; however, only the effect on DBP reached statistical significance. A subanalysis suggests that the effect on DBP may be stronger in losartan-treated than lisinopril-treated patients. A relatively strong placebo effect may limit data interpretation. Nebivolol was well tolerated, as there was no difference in TEAEs between nebivolol and placebo.

FUNDING

This trial (NCT00734630) was funded by Forest Laboratories, Inc.

Single oral dose pharmacokinetics of decursin, decursinol angelate, and decursinol in rats

Decursin and decursinol angelate are the major components in the alcoholic extract of the root of Angelica gigas Nakai. Our previous work convincingly demonstrated that both decursin and decursinol angelate were rapidly converted to decursinol in mice after administration by either oral gavage or i. p. injection. In the current study, we compared for the first time the plasma profiles of decursinol, when equal moles of decursin/decursinol angelate or decursinol were given to rats by oral gavage, and investigated the effect of different formulas and other chemicals in Angelica gigas extract on the bioavailability of decursinol. Our results show that gavage of decursinol led to a faster attainment of plasma decursinol peak (Tmax ~ 0.7 h) and much higher peak levels than an equal molar amount administered as decursin/decursinol angelate mixture or as Angelica gigas ethanol extract, resulting in 2-3 fold higher bioavailability as estimated by the area under the curve of the respective regimens (65 012 vs. 27 033 h · ng/mL for decursinol and decursin/decursinol angelate treatment groups, respectively). Compared to a formula based on ethanol-PEG400-Tween80, carboxyl methyl cellulose was a less optimized vehicle. In addition, we detected peak levels of decursin and decursinol angelate in the plasma of rats administered with decursin/decursinol angelate or Angelica gigas extract in the nM range (Tmax ~ 0.5 h) with a newly established sensitive UHPLC-MS/MS method. Furthermore, our data support the liver, instead of intestine, as a major organ site where decursin and decursinol angelate were hydrolyzed to decursinol with a S9 microsomal in vitro metabolism assay. Taken together, our study provided important PK, LC-MS/MS methodology, formulation and metabolism insights in a rodent model for the rational design of in vivo efficacy studies of the corresponding chemicals in the future.

Nebivolol monotherapy for patients with systolic stage II hypertension: results of a randomized, placebo-controlled trial

BACKGROUND

Elevated systolic blood pressure (SBP) is an independent risk factor for cardiovascular events and mortality.

OBJECTIVE

The goal of this study was to assess whether nebivolol (NEB), a vasodilatory β(1)-selective blocker, is a safe and efficacious monotherapy for individuals with systolic stage II hypertension.

METHODS

In this multicenter trial, 18- to 64-year-olds who had not used antihypertensive treatment for at least 4 weeks and had SBP/diastolic blood pressure (DBP) of 160 to 180/90 to 110 mm Hg were randomized to receive double-blind medication for 6 weeks (NEB, n = 290; placebo [PBO], n = 142). Depending on response, the starting dose (5 mg/d) could be increased directly to 20 mg/d. Primary parameters were baseline-end point changes in trough seated SBP and DBP (intent-to-treat [ITT] population); the Hochberg method was used to control the type I error (α = 0.05). Responder analysis was also performed. Safety and tolerability assessment included monitoring of adverse events (AEs).

RESULTS

Mean age at baseline (ITT) was 50.7 years, and the mean SBP/DBP values were 167/101 mm Hg; 202 (47.3%) participants were women, 276 (63.9%) had body mass index ≥30 kg/m(2), 152 (35.2%) were black, and 161 (37.3%) were Hispanic. Completion rates were 79.7% (PBO) and 90.3% (NEB). After 2 weeks of treatment, 92% and 95% participants in the NEB and PBO groups, respectively, had SBP in the range of 130 to 180 mm Hg and were titrated to the 20-mg/d NEB dose or its matching PBO tablet. After 6 weeks of treatment, the NEB group experienced significant mean reductions compared with the PBO group for both SBP (-18.2 vs -12.3 mm Hg; P < 0.001) and DBP (-12.3 vs -5.7 mm Hg; P < 0.001), down to mean SBP/DBP values of 149/89 mm Hg and 155/95 mm Hg, respectively, and had a significantly higher percentage of individuals who achieved BP control (SBP/DBP <140/90 mm Hg, 30.6% vs 17.3%; P = 0.004). Post hoc analyses suggest that NEB was not efficacious in reducing SBP in black participants. Mean changes in pulse rate were -12.8 beats/min for the NEB group and -1.6 beats/min for the PBO group (P < 0.001). Rates of discontinuations due to an AE (NEB vs PBO) were 1.4% in both groups, rates of any treatment-emergent AEs were 19.7% versus 19.0%, and rates of serious AEs were 0.3% versus 2.1%. The most common AEs (NEB vs PBO) were headache (2.1% vs 2.8%) and hypertension (0.7% vs 2.1%).

CONCLUSIONS

NEB monotherapy was an efficacious and well-tolerated treatment option for these study individuals with systolic stage II hypertension, but most of them would need combination therapy to achieve BP control.

A (S)-(+)-decursin derivative, (S)-(+)-3-(3,4-dihydroxy-phenyl)-acrylic acid 2,2-dimethyl-8-oxo-3,4-dihydro-2H,8H-pyrano[3,2-g]-chromen-3-yl-ester, attenuates the development of atopic dermatitis-like lesions in NC/Nga mice

(S)-(+)-decursin is a biological coumarin compound isolated from Angelica gigas Nakai. (S)-(+)-decursin and its analogue have a variety of pharmacological activities. In the present study, the anti-inflammatory effect of a (S)-(+)-decursin derivative, (S)-(+)-3-(3,4-dihydroxy-phenyl)-acrylic acid 2,2-dimethyl-8-oxo-3,4-dihydro-2H,8H-pyrano [3,2-g]-chromen-3-yl-ester (Compound 6, C6), on in vitro and in vivo atopic dermatitis was investigated. C6 suppressed the secretion of IL-6, IL-8, and monocyte chemotactic protein-1 increase by the house dust mite extract in the eosinophilic leukemia cell line and THP-1 cells. C6 inhibited the production of TARC, IL-6, and IL-8 increase by IFN-γ and TNF-α in the human keratinocyte cell line. In the in vivo experiment, NC/Nga mice were sensitized to 2,4-dinitrochlorobenzene, and then C6 or dexamethasone (Dex) were orally and dorsally administered for three weeks. C6 treatment reduced the skin severity score compared with that of the control group. C6 inhibited the thickening of the epidermis and inflammatory cell infiltration into the dermis by evaluating the histological examination. The serum immunoglobulin E (IgE) level decreased in the C6-treated group compared with that of the control group. The inhibitory effect of C6 on IgE concentration was similar to that of Dex. The levels of IL-4, IL-5, IL-13, and eotaxin increased after treatment with concanavalin A in mouse splenocytes. The cytokine levels of the C6-treated group were lower than those of the control group. Taken together, C6 may attenuate atopic dermatitis-like lesions through its anti-inflammatory effect, such as inhibition of IgE and inflammatory cytokines, and it may be valuable as a therapeutic drug for the treatment of atopic dermatitis.

Chebulic acid attenuates ischemia reperfusion induced biochemical alteration in diabetic rats

CONTEXT

Diabetic nephropathy is one of the important microvascular complications of diabetes; however, the main problem remains is the control of progression of nephropathy in diabetes. Chebulic acid was selected, as tannins from Terminalia chebula are used as antidiabetic, renoprotective, antioxidant, hypotensive and an α-glucosidase inhibitor.

OBJECTIVE

In this study, we evaluated the effect of chebulic acid on ischemia reperfusion induced biochemical alteration in diabetic rats.

MATERIALS AND METHODS

Chebulic acid (CA) was isolated from T. chebula; LD(50) and acute toxicity studies of CA were done. Renal ischemia and reperfusion technique was used to induce nephropathy in diabetic rats. Glibenclamide (10 mg/kg) was used as diabetic standard; CA at doses of 25 and 50 mg/kg were administered for 28 days and various biochemical parameters were monitored.

RESULTS

The LD(50) was found to be 251 mg/kg; 25 and 50 mg/kg doses were selected as no toxic symptoms were observed at both doses, except slight diarrhea. CA significantly (p < 0.001) reduced the glucose, creatinine, urea nitrogen, glycosylated hemoglobulin, proteinuria, urine albumin excretion, glomerular filtration rate (GFR), and increased serum insulin and glycogen level. CA also restored glucose 6-phosphate dehydrogenase, glutathione, superoxide dismutase, catalase and malondialdehyde levels. Improvement in kidney was also noted in histopathological studies.

CONCLUSIONS

The statistical data indicated that chebulic acid at both doses (25 and 50 mg/kg) improves biochemical alterations caused by renal ischemia in diabetic rats.

[Effect of monotherapy with nebivolol, bisoprolol, carvedilol on the state of vegetative nervous system and sexual function in men with arterial hypertension]

Aim of the study was to assess effect of monotherapy with nebivolol, bisoprolol, carvedilol for 2 months on sexual function in men with arterial hypertension (AH). Men with 1-2 degree of AH (n=75, age 35-55 years, mean age 48+/-3,5 years) received monotherapy with these drugs for 2 months. Registration of parameters of heart rate variability (HRV), Dopplerography of penile arteries, and the Vasilchenko questionnaire were implemented at the end of 4 months of placebo period and after 2 months of therapy with a study drug. Therapy with bisoprolol, carvedilol, and nebivolol was associated with significant elevation of parasympathetic part of vegetative nervous system tone, improvement of systolic blood flow in cavernous and dorsal arteries. Analysis of data obtained by Vasilchenko questionnaire demonstrated improvement of psychic and erectile components of sexual function. Thus bisoprolol, carvedilol, and nebivolol did not worsen sexual function of men with AH, improved spectral parameters of HRV and vascular blood flow in arteries of cavernous bodies.

Protective effect of chromene isolated from Sargassum horneri against UV-A-induced damage in skin dermal fibroblasts

Skin homoeostasis is interrupted during UV-A irradiation. How the UV-A-altered skin components influences photoageing of skin should be investigated using human in vitro models that are important for understanding skin ageing. In this study, chromene compound, sargachromenol, was isolated from Sargassum horneri, and its potency on inhibition of photoageing was investigated in UV-A-irradiated dermal fibroblasts. Effects of sargachromenol on the prevention of photoageing were evaluated by measuring ROS production, membrane protein oxidation, lipid peroxidation and ageing-related gene expression in UV-A-irradiated human skin dermal fibroblasts. The results indicated that treatment with sargachromenol suppressed the collagenase matrix metalloproteinases (MMPs), MMP-1, MMP-2 and MMP-9 expression without any cytotoxicity and phototoxicity. It was further found that these inhibitions were because of increase in the expression of TIMP-1 and TIMP-2 genes. Furthermore, we confirmed that the UV-A-induced transcriptions of AP-1 signalling pathway were regulated by sargachromenol treatment in UV-A-irradiated dermal fibroblasts.

Anti-inflammatory effect of sargachromanol G isolated from Sargassum siliquastrum in RAW 264.7 cells

A study on the anti-inflammatory activity of brown alga Sargassum siliquastrum led to the isolation of sargachromanol G (SG). In this study, the anti-inflammatory effect and the action mechanism of SG have been investigated in murine macrophage cell line RAW 264.7. SG dosedependently inhibited the production of inflammatory markers [nitric oxide (NO), inducible nitric oxide synthase (iNOS), prostaglandin E(2) (PGE(2)), and cyclooxygenase-2 (COX-2)] and pro-inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6] induced by LPS treatment. To further elucidate the mechanism of this inhibitory effect of SG, we studied LPS-induced nuclear factor-κB (NF-κB) activation and mitogen-activated protein kinases (MAPKs) phosphorylation. SG inhibited the phosphorylation IκB-α and NF-κB (p65 and p50) and MAPK (ERK1/2, JNK, and p38) in a dose dependent manner. These results suggest that the anti-inflammatory activity of SG results from its modulation of pro-inflammatory cytokines and mediators via the suppression of NF-κB activation and MAPK phosphorylation.

Protective effects of nebivolol against anthracycline-induced cardiomyopathy: a randomized control study

BACKGROUND

We aimed to evaluate the effect of prophylactic nebivolol use on prevention of antracycline-induced cardiotoxicity in breast cancer patients.

METHODS

In this small, prospective, double-blind study, we randomly assigned 45 consecutive patients with breast cancer and planned chemotheraphy to receive nebivolol 5mg daily (n=27) or placebo (n=18). Echocardiographic measurements and N-terminal pro-brain natriuretic peptide (NT-pro-BNP) levels were obtained at baseline and at 6-month of chemotherapy.

RESULTS

Both studied groups had comparable echocardiographic variables and NT-pro-BNP levels at baseline. At 6-month, the left ventricular (LV) end-systolic and end-diastolic diameters increased in the placebo group (LVESD: 29.7 ± 3.4 to 33.4 ± 4.5mm; LVEDD: 47.2 ± 3.8 to 52.0 ± 4.6mm, p=0.01 for both) but remained unchanged in the nebivolol group (LVESD: 30.4 ± 3.5 to 31.0 ± 3.6mm, p=0.20; LVEDD: 47.0 ± 4.4 to 47.1 ± 4.0mm, p=0.93). The placebo group also had lower LVEF than the nebivolol group (57.5 ± 5.6% vs. 63.8 ± 3.9%, p=0.01) at 6-month. NT-pro-BNP level remained static in the nebivolol group (147 ± 57 to 152 ± 69 pmol/l, p=0.77) while it increased in the placebo group (144 ± 66 to 204 ± 73 pmol/l, p=0.01).

CONCLUSIONS

Prophylactic use of nebivolol treatment may protect the myocardium against antracycline-induced cardiotoxicity in breast cancer patients.

First-pass metabolism of decursin, a bioactive compound of Angelica gigas, in rats

Decursin is considered the major bioactive compound of Angelica gigas roots, a popular Oriental herb and dietary supplement. In this study, the pharmacokinetics of decursin and its active metabolite, decursinol, were evaluated after the administration of decursin in rats. The plasma concentration of decursin decreased rapidly, with an initial half-life of 0.05 h. It was not detectable at 1 h after intravenous administration at an area under the plasma concentration-time curve of 1.20 µg · mL-1·h, whereas the concentration of decursinol increased rapidly reaching a maximum concentration of 2.48 µg · mL-1 at the time to maximum plasma concentration of 0.25 h and an area under the plasma concentration-time curve of 5.23 µg · mL-1·h. Interestingly, after oral administration of decursin, only decursinol was present in plasma, suggesting an extensive hepatic first-pass metabolism of decursin. The extremely low bioavailability of decursin after its administration via the hepatic portal vein (the fraction of dose escaping first-pass elimination in the liver, FH = 0.11) is indicative of extensive hepatic first-pass metabolism of decursin, which was confirmed by a tissue distribution study. These findings suggest that decursin is not directly associated with the bioactivity of A. gigas and that it may work as a type of natural prodrug of decursinol.

Anti-hyperglycemic effect of chebulagic acid from the fruits of Terminalia chebula Retz

In the present study, we firstly compared rat intestinal α-glucosidase inhibitory activity by different ethanol-aqueous extractions from the dried fruits of Terminalia chebula Retz. The enzymatic assay showed that the 80% ethanol extract was more potent against maltase activity than both 50% and 100% ethanol extracts. By HPLC analysis, it was determined that the 80% ethanol extract had a higher content of chebulagic acid than each of 50% or 100% ethanol extract. Next, we investigated how efficiently chebulagic acid could inhibit sugar digestion by determining the glucose level on the apical side of the Caco-2 cell monolayer. The result showed that the maltose-hydrolysis activity was down-regulated by chebulagic acid, which proved to be a reversible inhibitor of maltase in Caco-2 cells. On the other hand, chebulagic acid showed a weak inhibition of sucrose-hydrolysis activity. Meanwhile, chebulagic acid did not have an obvious influence on intestinal glucose uptake and was not effective on glucose transporters. Further animal studies revealed that the oral administration of chebulagic acid (100 mg/kg body weight) significantly reduced postprandial blood glucose levels by 11.1% in maltose-loaded Sprague-Dawley (SD) rats compared with the control group, whereas the oral administration of chebulagic acid did not show a suppressive effect on postprandial hyperglycemia in sucrose- or glucose-loaded SD-rats. The results presented here suggest that chebulagic acid from T. chebula can be used to control blood glucose and manage type 2 diabetes, although clinical trials are needed.

Persistence with nebivolol in the treatment of hypertension: a retrospective claims analysis

OBJECTIVE

Examine drug persistence by evaluating the hazard of discontinuation and of switching to different antihypertensive drugs in patients initiating treatment with a recently approved β-blocker, nebivolol, versus other β-blockers.

METHODS

This retrospective analysis included all patients diagnosed with hypertension in the MarketScan Database (January 2007 - December 2008) with at least two medical claims and no prior β-blocker prescriptions within 6 months of the initial prescription date. Multivariate Cox proportional hazard models (adjusted for baseline differences in demographics, previous use of other antihypertensive medications, initial doses and supply of medication, and number of distinct prescriptions at baseline) were used to assess the hazard of discontinuation, defined as the first prescription gap of ≥30 days, and to assess the hazard of switching to another antihypertensive drug, defined as a prescription fill for another antihypertensive drug within 15 days before and 30 days after discontinuation of the initial β-blocker.

RESULTS

Of the 173,200 patients included in the study population, the adjusted hazard of discontinuation for nebivolol-initiated patients was 8-20% lower than that of patients who initiated treatment with atenolol (hazard ratio [HR] 0.82, p < 0.001), metoprolol (HR 0.91, p < 0.001), carvedilol (HR 0.92, p < 0.001), or other β-blockers (HR 0.80, p < 0.001). The adjusted hazard of nebivolol-treated patients switching to a different antihypertensive medication was 12-22% lower than that of the other four β-blocker cohorts (atenolol: HR 0.80, p < 0.001; metoprolol: HR 0.86, p < 0.001; carvedilol: HR 0.88, p < 0.001; other β-blockers: HR 0.78, p < 0.001). Sensitivity analyses defined discontinuation as prescription gaps of ≥45 days and ≥60 days and showed a lower hazard of discontinuation among patients initiating nebivolol than among patients initiating all other drug cohorts (p < 0.001).

LIMITATIONS

Comparisons of non-randomized treatment groups may be confounded by unobserved differences in patients' baseline characteristics.

CONCLUSIONS

Initiation with nebivolol was associated with greater persistence than initiation with atenolol, carvedilol, metoprolol, or other β-blockers.

The use of beta blocker Nebivolol in patients with chronic obstructive pulmonary disease in association with arterial hypertension

There were investigated 22 patients with chronic obstructive pulmonary disease in association with arterial hypertension initially and after 5 weeks of treatment with beta-blocker Nebivolol 5 mg/day. There were not detected any negative changes on bronchial permeability after treatment. Considerable improvement of endothelial function (from 7-12% to 17-35%, p < 0.05) in parallel with decreasing of pulmonary artery, systolic (44.5 +/- 5.5 mmHg vs. 32.8 +/- 4.1 mmHg, p < 0.05) and mean pressure (26.3 +/- 4.2 mmHg vs. 21.1 +/- 2.1 mmHg, p < 0.05)--were observed after treatment. Thus, Nebilet is well-tolerated and highly effective in patients with chronic obstructive pulmonary disease in association with arterial hypertension.

[Use of nebivolol in patients with idiopathic pulmonary hypertension: results of the pilot study]

AIM

To study the impact of 24-week therapy with nebivolol in a dose of 5 mg/day on the clinical and functional status of patients with idiopathic pulmonary hypertension (IPH), echocardiographic parameters, and blood levels of vasoactive mediators and nitric oxide (NO) metabolite.

SUBJECTS AND METHODS

During continuous standard therapy comprising dihydropyridine calcium antagonists, warfarin, and diuretics, 12 patients with IPH and functional class (FC) II-III received nebivolol in a dose of 5 mg/day for 24 weeks. According to the data of right heart catheterization, all the patients had a positive acute pharmacological test with a vasodilator (NO). Six-minute walk test (6'WT), estimation of the Borg dyspnea index (BDI) and FC, transthoracic echocardiography (EchoCG), and measurements of the levels of NO metabolites, endothelin-1, (ET-1), thromboxane B2 (TxB2), and 6-keto-prostaglandin F1alpha (6-ketoPG F1alpha) were done at baseline and after 12 and 24 weeks of the therapy.

RESULTS

Following 24-week nebivolol treatment, there was a statistically significant increase in 6'WT distance (from 473 +/- 47.6 to 516.7 +/- 58.4 m; p < 0.0001) and a drop in BDI (from 3.4 +/- 2.2 to 1.1 +/- 0.7; p < 0.05) and FC (from 2.9 +/- 0.4 to 1.7 +/- 0.2; p < 0.05). Doppler EchoCG showed that pulmonary artery systolic pressure statistically significantly decreased (91.6 +/- 30 to 78.3 +/- 39 mm Hg; p = 0.05) at 12 weeks and slightly increased up to 83.2 +/- 32.4 mm Hg at 24 weeks. After 24-week treatment, the anteroposterior dimensions of the right ventricle (RV) statistically significantly reduced (from 4.4 +/- 0.6 to 3.8 +/- 1.2 cm; p < 0.05). The other EchoCG parameters remained substantially unchanged. There was a statistically reduction in the level of ET-1 (from 2.99 +/- 1.1 to 2.17 +/- 0.8 micromol/l; p < 0.05). The concentrations of 6-ketoPG Fla, TxB2, and NO metabolite remained substantially unchanged at 24 weeks of treatment with nebivolol. There were no adverse reactions requiring that the dose of the drug be discontinued or reduced. Heart rate tended to be lower at a 24-week follow-up. All the patients continued taking nebivolol after completion of the study.

CONCLUSION

Therapy with nebivolol in a dose of 5 mg/day for 24 weeks led to a significant functional improvement in the patients with IPH and reductions in RV dimensions and blood ET-1 levels. The therapy did not cause adverse reactions.

[Analysis of variability of cardiac rhythm and sexual function in men with arterial hypertension during therapy with biosporolol and nebivolol]

The aim of the work was to study effect of bisoprolol and nebivolol therapy on the sexual function of men with AH. 20 men aged 35-55 (48 +/- 3.5) yr with grade I and II AH received either drug for 2 months. Cardiac rhythm variability (CRV) was estimated in the end of the 4-week placebo period and after 2-month monotherapy. Dopplerography of penile arteries and a questionnaire study (as described by Vasilchenko) were conducted. Both drugs significantly increased the tone of the parasympathetic component of the vegetative nervous system, improved systolic blood flow in cavernous and dorsal arteries. The questionnaire study failed to revel significant changes of the sexual function. It is concluded that biosporolol and nebivolol did not compromise the sexual function of men with AH; they improve spectral CRV characteristics and blood flow in cavernous arteries.