Pravastatin reverses the down-regulating effect of inflammation on β-Adrenergic receptors: A disease–drug interaction between inflammation, pravastatin, and propranolol

Mitochondrial DNA Release Contributes to Intestinal Ischemia/Reperfusion Injury

Mitochondria release many damage-associated molecular patterns (DAMPs) when cells are damaged or stressed, with mitochondrial DNA (mtDNA) being. MtDNA activates innate immune responses and induces inflammation through the TLR-9, NLRP3 inflammasome, and cGAS-STING signaling pathways. Released inflammatory factors cause damage to intestinal barrier function. Many bacteria and endotoxins migrate to the circulatory system and lymphatic system, leading to systemic inflammatory response syndrome (SIRS) and even damaging the function of multiple organs throughout the body. This process may ultimately lead to multiple organ dysfunction syndrome (MODS). Recent studies have shown that various factors, such as the release of mtDNA and the massive infiltration of inflammatory factors, can cause intestinal ischemia/reperfusion (I/R) injury. This destroys intestinal barrier function, induces an inflammatory storm, leads to SIRS, increases the vulnerability of organs, and develops into MODS. Mitophagy eliminates dysfunctional mitochondria to maintain cellular homeostasis. This review discusses mtDNA release during the pathogenesis of intestinal I/R and summarizes methods for the prevention or treatment of intestinal I/R. We also discuss the effects of inflammation and increased intestinal barrier permeability on drugs.

Animal models to study pathogenesis and treatments of cardiac disorders in rheumatoid arthritis: Advances and challenges for clinical translation

Although cardiac diseases such as acute myocardial infarction, heart failure and arrhythmias are the leading cause of cardiovascular complications in rheumatoid arthritis (RA), their pathogenesis is far from being understood and optimal therapeutic options to treat specifically these disorders in RA are lacking. Preclinical studies on animal models of arthritis can help to decipher the complex link between arthritis and the heart, and to identify critical pathways and novel therapeutic targets. This review presented the available data on cardiac disorders in animal models of RA, as well as the current knowledge on pathophysiology and pharmacology of these disorders. Future directions for translational studies in a cardiorheumatic perspective are proposed.

Statins enhance cognitive performance in object location test in albino Swiss mice: involvement of beta-adrenoceptors

Statins are inhibitors of the 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, thereby inhibiting cell synthesis of cholesterol and isoprenoids. Moreover, several studies have been evaluating pleiotropic effects of statins, mainly because they present neuroprotective effects in various pathological conditions. However, knowledge about behavioral effects of statins per se is relatively scarce. Considering these facts, we aimed to analyze behavioral responses of atorvastatin or simvastatin-treated mice in the open field test, elevated plus maze and object location test. Atorvastatin treatment for 7 consecutive days at 1 mg/kg or 10 mg/kg (v.o.) or simvastatin 10 mg/kg or 20 mg/kg enhanced cognitive performance in object location test when compared to control group (saline-treated mice). Simvastatin effects on mice performance in the object location test was abolished by post-training infusion of the beta-adrenoceptor antagonist propranolol. Atorvastatin and simvastatin did not change the behavioral response in open field and elevated plus-maze (EPM) tests in any of the used doses. These data demonstrate the positive effects of both statins in cognitive processes in mice, without any alteration in locomotor parameters in the open field test or anxiolytic-like behavior in EPM. In conclusion, we demonstrate that atorvastatin and simvastatin per se improve the cognitive performance in a rodent model of spatial memory and this effect is related to beta-adrenergic receptors modulation.

Drug-disease interaction: Crohn's disease elevates verapamil plasma concentrations but reduces response to the drug proportional to disease activity

AIM

Inflammation is involved in the pathogenesis of cardiovascular diseases that includes reduced response to pharmacotherapy due to altered pharmacokinetics and pharmacodynamics. It is not known if these effects exist in general in all inflammatory conditions. It also remains unknown whether in a given population the effect is a function of disease severity. We investigated whether pharmacokinetics and pharmacodynamics of a typical calcium channel inhibitor are influenced by Crohn's disease (CD), a disease for which the disease severity can be readily ranked.

METHODS

We administered 80 mg verapamil orally to (i) healthy control subjects (n= 9), (ii) patients with clinically quiescent CD (n= 22) and (iii) patients with clinically active CD (n= 14). Serial analysis of verapamil enantiomers (total and plasma unbound), blood pressure and electrocardiograms were recorded over 8 h post dose. The severity of CD was measured using the Harvey-Bradshaw Index.

RESULTS

CD substantially and significantly increased plasma verapamil concentration and in a stereoselective fashion (S, 9-fold; R, 2-fold). The elevated verapamil concentration, however, failed to result in an increased verapamil pharmacodynamic effect so that the patients with elevated verapamil concentration demonstrated no significant increase in response measured as PR interval and blood pressure. Instead, the greater the disease severity, the lower was the drug potency to prolong PR interval (r= 0.86, P < 0.0006),

CONCLUSIONS

CD patients with severe disease may not respond to cardiovascular therapy with calcium channel blockers. Reducing the severity increases response despite reduced drug concentration. This observation may have therapeutic implication beyond the disease and the drug studies herein.

The effect of infliximab on hepatic cytochrome P450 and pharmacokinetics of verapamil in rats with pre-adjuvant arthritis: a drug-disease and drug-drug interaction

Inflammatory conditions result in increased concentration but reduced potency of some cardiovascular drugs. This is associated with increased levels of pro-inflammatory mediators. Infliximab reduces pro-inflammatory mediators and reverses the diminishing effect of inflammation on response in the rat. We suggested that infliximab treatment would also reverse the effects of inflammation on drug metabolism and clearance. We examined hepatic cytochrome P450 content and the pharmacokinetics of verapamil in pre-adjuvant arthritic rats treated with infliximab. Pre-adjuvant arthritis was induced in male Sprague-Dawley rats with a tail base injection of Mycobacterium butyricum. Animals were monitored for symptoms of arthritis, serum nitrite and C-reactive protein. On day 6, rats were administered with single s.c. doses of infliximab (10 mg/kg). On day 14, a single i.v. dose of racemic verapamil (2 mg/kg) was administered, and S- and R-verapamil concentrations were determined by high performance liquid chromatography. Hepatic cytochrome P450 content and verapamil protein binding were also measured. Serum nitrite levels were significantly elevated in pre-adjuvant arthritis. Infliximab did not affect mean nitrite concentrations but there was a significant correlation between nitrite and S-verapamil concentrations as well as cytochrome P450, CYP3A, and CYP1A contents. Infliximab increased cytochrome P450 enzymes content that had been diminished by pre-adjuvant arthritis but had no significant effect on verapamil protein binding. Infliximab partially restores hepatic cytochrome P450 enzyme contents. The effect of infliximab on the mean verapamil clearance was not significantly affected due, likely, to the lack of effect on plasma protein binding.

Effect of obesity on response to cardiovascular drugs in pediatric patients with renal disease

Obesity is associated with an increased concentration of inflammatory mediators, which in turn, in adults, reduces the response to calcium channel blockers (CCBs). We reviewed the medical charts of 263 pediatric nephrology patients with renal conditions, with the aim of studying the effect of obesity on the response to L-type CCBs, angiotensin interrupting agents (ANGIs), or a combination of the two. Forty-eight patients were ultimately enrolled in the study: 25 obese and 23 non-obese patients. The effect of the treatments on lowering the blood pressure was compared in obese versus non-obese patients. The systolic response to CCBs, measured as at least a 10% reduction from the baseline, was significantly lower in the obese (12.5%) patients than in the non-obese (52.9%) ones. The differences in diastolic response (58.8 and 25% for non-obese and obese patients, respectively) did not reach significance. The percentage response to CCBs, however, was significantly less in the obese patients than in the non-obese patients for both systolic and diastolic blood pressure. Corticosteroids also significantly influenced the response to CCBs in terms of diastolic pressure (62.9 and 25% for non-obese and obese patients, respectively). None of the tested covariates, including obesity, was found to significantly influence the response to ANGIs alone or in various combinations with CCBs. In conclusion, obesity and corticosteroid therapy should be considered when initiating antihypertensive drug treatment in children with kidney disease as both may contribute to a reduced efficacy of the antihypertensive therapy.

Influence of controlled rheumatoid arthritis on the action and disposition of verapamil: focus on infliximab

Active rheumatoid arthritis (RA), obesity, and old age are associated with reduced responsiveness to the calcium channel antagonist verapamil despite increased drug concentrations. The diminishing effect appears to be associated with the severity of inflammation. We examined pharmacodynamics and pharmacokinetics of verapamil in patients with controlled RA. Volunteers included RA patients in remission: 12 on infliximab, 8 on other antirheumatic therapy, and 12 healthy subjects. Verapamil plasma concentrations and selected inflammatory mediators as well as blood pressure and electrocardiographic parameters were recorded after a single 80-mg dose of verapamil. Inflammatory mediators were all below what is reported for active RA, confirming that RA was controlled. The tumor necrosis factor-alpha concentration, however, was significantly higher in the infliximab group compared with other groups and the literature value for active RA. No significant difference was observed between groups in terms of percentage prolongation of PR interval despite a trend toward a lower response in the RA groups, the mean plasma concentrations, and the total and unbound area under the curve of verapamil. However, the slope of the S-verapamil concentration-effect curve was steeper for controls compared with the RA patients. Remission from active disease appears to restore plasma protein levels and hepatic drug metabolism activity in patients with RA, resulting in relatively normal verapamil pharmacokinetics.

Effects of inflammation on pharmacokinetics/pharmacodynamics: increasing recognition of its contribution to variability in response

Inflammation is an interesting phenomenon that crosses many disciplines as part of the host response to disease, whether it is the acute response to an infectious, traumatic, or surgical event or the more chronic responses to systemic disease such as malignancy, rheumatoid arthritis, asthma, inflammatory bowel disease, or diabetes. The impact of inflammatory states on the variability in drug response should be an integral part of research conducted across disciplines within clinical pharmacology.

Effects of angiotensin II blockade on inflammation-induced alterations of pharmacokinetics and pharmacodynamics of calcium channel blockers

BACKGROUND AND PURPOSE

Inflammation elevates plasma verapamil concentrations but diminishes pharmacological response. Angiotensin II is a pro-inflammatory mediator. We examined the effect of angiotensin II receptor blockade on the pharmacokinetics and pharmacodynamics of verapamil, as well as the binding properties and amounts of its target protein in calcium channels, in a rat model of inflammation.

EXPERIMENTAL APPROACH

We used 4 groups of male Sprague-Dawley rats (220-280 g): inflamed-placebo, inflamed-treated, control-placebo and control-treated. Inflammation as pre-adjuvant arthritis was induced by injecting Mycobacterium butyricum on day 0. From day 6 to 12, 30 mg kg(-1) oral valsartan or placebo was administered twice daily. On day 12, a single oral dose of 25 mg kg(-1) verapamil was administered and prolongation of the PR interval measured and plasma samples collected for verapamil and nor-verapamil analysis. The amounts of the target protein Ca(v)1.2 subunit of L-type calcium channels in heart was measured by Western blotting and ligand binding with (3)H-nitrendipine.

KEY RESULTS

Inflammation reduced effects of verapamil, although plasma drug concentrations were increased. This was associated with a reduction in ligand binding capacity and amount of the calcium channel target protein in heart extracts. Valsartan significantly reversed the down-regulating effect of inflammation on verapamil's effects on the PR interval, and the lower level of protein binding and the decreased target protein.

CONCLUSIONS AND IMPLICATIONS

Reduced responses to calcium channel blockers in inflammatory conditions appeared to be due to a reduced amount of target protein that was reversed by the angiotensin II antagonist, valsartan.