Ibuprofen arginate retains eNOS substrate activity and reverses endothelial dysfunction: implications for the COX-2/ADMA axis

Low-dose aspirin inhibits trophoblast cell apoptosis by activating the CREB/Bcl-2 pathway in pre-eclampsia

Excessive apoptosis of placental trophoblast cells is considered a major cause of pre-eclampsia (PE) pathogenesis. Phosphorylation of the widely expressed cAMP response element binding protein (CREB) regulates apoptosis and may be involved in PE incidence. Low-dose aspirin (LDA) is an effective approach for preventing PE with unclear mechanisms. Thus we examined whether LDA protects against PE by inhibiting trophoblast cell apoptosis through CREB. The effects of LDA on human PE placenta, PE model rat placenta, and hydrogen peroxide (H2O2)-induced HTR-8/SVneo cell apoptosis were analyzed. TUNEL assay, immunohistochemistry, Cell Counting Assay Kit-8 (CCK-8) assay, western blot, and flow cytometry assay were performed. In the placenta of human PE and rat PE models, the TUNEL index increased and was partially corrected with LDA pre-treatment. Meanwhile, decreased Bcl-2 and increased Bax expression were significantly reversed by LDA pre-treatment. In HTR-8/SVneo cells, H2O2 decreased cell viability, promoted apoptosis, reduced the Bcl-2/Bax ratio, aggravated loss of mitochondrial membrane potential (MMP), increased cytoplasmic cytochrome c release, and simultaneously activated caspase-9 and caspase-3. These effects were effectively restored by LDA pre-treatment in the cells. Moreover, LDA promoted CREB phosphorylation in trophoblast cells. CREB interference further promoted apoptosis, reduced the Bcl-2/Bax ratio, and increased MMP loss. CREB interference also reversed the inhibitory effect of LDA on H2O2-induced apoptosis in HTR-8/SVneo cells. Thus, LDA was shown to inhibit trophoblast cell mitochondrial apoptosis by activating the CREB/Bcl-2 pathway, providing novel evidence for the protective mechanism of LDA in PE.Abbreviations; PE: Pre-eclampsia; LDA: low-dose aspirin; CREB: cAMP response element binding protein; ROS: reactive oxygen species; H2O2: hydrogen peroxide; PBS: Phosphate-buffered saline; Bcl-2: B-cell lymphoma-2; MMP: Mitochondrial membrane potential; Cyt-c: CytochromeC.

Association of proton pump inhibitor use with endothelial function and metabolites of the nitric oxide pathway: A cross-sectional study

STUDY OBJECTIVE

Long-term intake of proton pump inhibitors (PPIs) might increase the risk of cardiovascular events. One suggested mechanism is that PPIs inhibit the enzyme dimethylarginine dimethylaminohydrolase (DDAH) and thereby block the degradation of endothelial asymmetrical dimethylarginine (ADMA). Excess ADMA in turn leads to impaired endothelial nitric oxide (NO) generation. So far, this mechanism has only been established in human cell cultures. Previous studies that examined this pathway in human populations measured circulating ADMA and found no association with PPI use and excess plasma ADMA. But in a recent study, plasma ADMA was not correlated with intracellular ADMA. We therefore focused on changes in plasma citrulline as an indicator for potential DDAH inhibition.

DESIGN

We analyzed the association between regular daily PPI intake and flow-mediated dilation (FMD) of the brachial artery as well as plasma concentrations of citrulline, arginine, ADMA, and symmetric dimethylarginine using inverse probability weighting to adjust for confounding and censoring.

DATA SOURCE

Data of 1298 participants from two independent cohorts of the population-based Study of Health in Pomerania were used.

PATIENTS

Participants of the population-based Study of Health in Pomerania are a stratified random sample of the study region.

INTERVENTION

Regular daily intake of PPIs.

MEASUREMENTS

FMD of the brachial artery and plasma concentrations of citrulline, arginine, ADMA, and symmetric dimethylarginine.

MAIN RESULTS

Eighty-seven participants (57.5% female) were regular daily users of PPIs. In the fully adjusted models, associations were identified for FMD and plasma citrulline concentrations. PPI users revealed a 0.99% (95% CI: -1.96 to -0.02) lower FMD and 3.03 µmol/L (95% CI: -4.96 to -1.10) lower plasma citrulline levels as compared to non-users.

CONCLUSION

Our data provide evidence that long-term intake of PPIs might inhibit human DDAH activity, resulting in impaired endothelial NO production and reduced vascular function. In the long run, this might explain an increased risk for cardiovascular diseases associated with long-term PPI use.

Ibuprofen Arginate for Rapid-Onset Pain Relief in Daily Practice: A Review of Its Use in Different Pain Conditions

Ibuprofen is one of the most frequently used analgesics. One of the concerns related with the oral administration of conventional ibuprofen is the relatively slow absorption, which is clinically a relative inconvenience when rapid-onset analgesic effect is required in patients suffering from acute moderate/severe pain. A new oral dosage formulation of ibuprofen containing the L-arginine salt of ibuprofen (ibuprofen arginate) has been commercialized for more than two decades, but data reported in the literature are relatively scarce. This article presents salient findings on pharmacokinetics, pharmacological activity, clinical efficacy and tolerability of ibuprofen arginate, with the purpose to provide clinicians with a summary overview of some frequent acute pain conditions, such as dental pain, dysmenorrhea, headache or postoperative pain in which ibuprofen arginate may be considered the drug of choice in individual patients.

The prospective curative role of lipoxin A4 in induced gastric ulcer in rats: Possible involvement of mitochondrial dynamics signaling pathway

This study purposed to examine the prospective curative role of lipoxin A₄ (LXA₄ ) in induced gastric ulcer in rats and explore the possible involvement of mitochondrial dynamics signaling pathway. Forty-eight male Wistar rats were divided into four groups: control, indomethacin (IND), IND + omeprazole (IND + Omez), and IND+ LXA₄ groups. At the end of the experiment, the gastric pH, gastric fluid volume, total gastric acidity, ulcer index, and curative index were estimated. The gene expression of mitochondrial related protein 1 and mitofusin 2 were determined. In addition, some mitochondrial parameters include mitochondrial transmembrane potential, complex-I activity and reactive oxygen species were measured. Also, some gastric biochemical parameters, histopathological, and immunohistochemical analyses of the gastric mucosa were determined. We found that IND induced gastric ulcer, as manifested by the biochemical, histopathological, and immunohistochemical analyses. Both Omez and LXA₄ treatment for 15 days alleviated the IND-induced gastric ulcer as explored by ameliorating the biochemical, histopathological, and immunohistochemical findings. We concluded that LXA₄ mitigated the IND-induced gastric ulcer via improving the mitochondrial dynamic imbalance and mitochondrial dysfunction, in addition to its anti-apoptotic, anti-inflammatory, and antioxidant properties.

Enhancement of ibuprofen solubility and skin permeation by conjugation with l-valine alkyl esters

New ibuprofen derivatives were made via conjugation with l-valine alkyl esters (ValOR), where R was changed from an ethyl to a hexyl group. The ionic structure was confirmed using NMR and FTIR. Specific rotation, solubility in commonly used solvents, thermal properties including phase transitions temperatures, and thermal stability were also determined. The ionic structure with a protonated amine group on an l-valine ester and melting points below 100 °C allowed inclusion of these ibuprofen derivatives into the pharmaceutically active protic ionic liquids. The ibuprofen salt solubility in deionised water and two buffer solutions at pH 5.4 and 7.4 were established and compared with the parent acid solubility. The octanol/water (buffer) partition coefficient, permeation through porcine skin, and accumulation in the skin were also measured. Ibuprofen pairing with l-valine alkyl esters [ValOR][IBU], caused higher solubility and a greater drug molecule absorption through biological membranes. log P was lower for ibuprofen salts than for the acid and it increased with a longer l-valine ester cation alkyl chain. In vitro porcine skin tests showed that ibuprofen salts with a propyl or isopropyl ester in l-valine are particularly relevant for topical application. They provide transport for ibuprofen through the skin at much higher rate than the unmodified acid and a higher permeated ibuprofen concentration, which can improve efficacy. Thus, synthesised ibuprofen derivatives could be used as drug carriers in transdermal systems to provide better drug bioavailability, and they can be also be the source of exogenous l-valine.

New ibuprofen derivatives made via conjugation with l-valine alkyl esters have better solubility in aqueous solutions and a lower log P value compared to the parent acid. They provide faster and more completely permeation of drug through the skin.

Blueberry anthocyanin‑enriched extract ameliorates transverse aortic constriction‑induced myocardial dysfunction via the DDAH1/ADMA/NO signaling pathway in mice

Blueberry anthocyanin‑enriched extract (BAE) has been demonstrated to protect against cardiovascular diseases by activating multiple target genes. The present study investigated the effects of BAE on transverse aortic constriction (TAC)‑induced myocardial dysfunction in mice and explored its possible molecular mechanisms. A total of 30 male mice were divided randomly into control, TAC and TAC + BAE groups. Mice in the TAC + BAE groups were administered BAE by oral gavage for 6 consecutive weeks. Myocardial dysfunction was assessed using echocardiogram, histopathology, TUNEL assay, immunofluorescence staining, reverse transcription‑quantitative PCR and western blot analysis. The results demonstrated that BAE treatment significantly ameliorated heart weight, left ventricular weight, myocardial dysfunction, left ventricular hypertrophy and fibrosis. In addition, BAE treatment alleviated TAC‑induced inflammation, oxidative stress and apoptosis. Notably, BAE treatment markedly reduced asymmetric dimethylarginine (ADMA) concentration and significantly increased dimethylarginine dimethylaminohydrolase 1 (DDAH1) expression and nitric oxide (NO) production. The present data indicated that BAE treatment ameliorated TAC‑induced myocardial dysfunction, oxidative stress, inflammatory response and apoptosis via the DDAH1/ADMA/NO signaling pathway.

Diclofenac but not celecoxib improves endothelial function in rheumatoid arthritis: A study in adjuvant-induced arthritis

BACKGROUND AND AIMS

We aimed at investigating the effect of celecoxib (COX-2 selective inhibitor) and diclofenac (non-selective COX inhibitor) on endothelial function, and at identifying the underlying mechanisms in adjuvant-induced arthritis (AIA).

METHODS

At the first signs of AIA, diclofenac (5 mg/kg twice a day, i.p), celecoxib (3 mg/kg/day, i.p) or saline (Vehicle) was administered for 3 weeks. Endothelial function was studied in aortic rings relaxed with acetylcholine (Ach) with or without inhibitors of NOS, arginase, EDHF and superoxide anions (O₂^-°) production. Aortic expression of eNOS, Ser1177-phospho-eNOS, COX-2, arginase-2, p22^phox and p47^phox was evaluated by Western blotting analysis. Arthritis scores, blood pressure, glycaemia and serum ADMA levels were measured.

RESULTS

Diclofenac and celecoxib significantly reduced arthritis score to the same extent (p<0.05). As compared to vehicle-treated AIA, celecoxib did not change whereas diclofenac improved endothelial function (p<0.05) through increased EDHF production, decreased arginase activity and expression, decreased superoxide anions production and expression of p22^phox and p47^phox. Diclofenac but not celecoxib significantly enhanced blood pressure and serum ADMA levels. Glycaemia was unchanged by both treatments.

CONCLUSIONS

Our study reveals that the effect of NSAIDs on endothelial function cannot be extrapolated from their impact on arthritis severity and suggest that changes in blood pressure and plasma ADMA levels may not be useful to predict CV risk of NSAIDs in RA.

Pharmacological assessment of ibuprofen arginate on platelet aggregation and colon cancer cell killing

Nonsteroidal anti-inflammatory drugs (NSAIDs), including ibuprofen, are amongst the most commonly used medications and produce their anti-inflammatory and analgesic benefits by blocking cyclooxygenase (COX)-2. These drugs also have the potential to prevent and treat cancer and some members of the class including ibuprofen can produce anti-platelet effects. Despite their utility, all NSAIDs are associated with increased risk of cardiovascular side effects which our recent work suggests could be mediated by increased levels of the endogenous NO synthase (NOS) inhibitor asymmetric dimethylarginine (ADMA) leading to reduced endothelial NOS activity and associated endothelial cell dysfunction. ADMA is a cardiotoxic hormone and biomarker of cardiovascular risk whose effects can be prevented by l-arginine. The ibuprofen salt, ibuprofen arginate (Spididol^®) was created to increase drug solubility but we have previously established that it not only effectively blocks COX-2 but also provides an arginine source able to reverse the effects of ADMA in vitro and in vivo. Here we have gone on to explore whether the formulation of ibuprofen with arginine influences the potency and efficacy of the parent molecule using a range of simple in vitro assays designed to test the effects of NSAIDs on (i) platelet aggregation and (iii) colon cancer cell killing. Our findings demonstrate that ibuprofen arginate retains these key functional effects of NSAIDs with similar or increased potency compared to ibuprofen sodium, further illustrating the potential of ibuprofen arginate as an efficacious drug with the possibility of improved cardiovascular safety.