Glutathione and glutathione-dependent enzymes: From biochemistry to gerontology and successful aging.

The tripeptide glutathione (GSH), namely γ-L-glutamyl-L-cysteinyl-glycine, is an ubiquitous low-molecular weight thiol nucleophile and reductant of utmost importance, representing the central redox agent of most aerobic organisms. GSH has vital functions involving also antioxidant protection, detoxification, redox homeostasis, cell signaling, iron metabolism/homeostasis, DNA synthesis, gene expression, cysteine/protein metabolism, and cell proliferation/differentiation or death including apoptosis and ferroptosis. Various functions of GSH are exerted in concert with GSH-dependent enzymes. Indeed, although GSH has direct scavenging antioxidant effects, its antioxidant function is substantially accomplished by glutathione peroxidase-catalyzed reactions with reductive removal of H2O2, organic peroxides such as lipid hydroperoxides, and peroxynitrite; to this antioxidant activity also contribute peroxiredoxins, enzymes further involved in redox signaling and chaperone activity. Moreover, the detoxifying function of GSH is basically exerted in conjunction with glutathione transferases, which have also antioxidant properties. GSH is synthesized in the cytosol by the ATP-dependent enzymes glutamate cysteine ligase (GCL), which catalyzes ligation of cysteine and glutamate forming γ-glutamylcysteine (γ-GC), and glutathione synthase, which adds glycine to γ-GC resulting in GSH formation; GCL is rate-limiting for GSH synthesis, as is the precursor amino acid cysteine, which may be supplemented as N-acetylcysteine (NAC), a therapeutically available compound. After its cell export, GSH is degraded extracellularly by the membrane-anchored ectoenzyme γ-glutamyl transferase, a process occurring, as GSH synthesis and export, in the γ-glutamyl cycle. GSH degradation occurs also intracellularly by the cytoplasmic enzymatic ChaC family of γ-glutamyl cyclotransferase. Synthesis and degradation of GSH, together with its export, translocation to cell organelles, utilization for multiple essential functions, and regeneration from glutathione disulfide by glutathione reductase, are relevant to GSH homeostasis and metabolism. Notably, GSH levels decline during aging, an alteration generally related to impaired GSH biosynthesis and leading to cell dysfunction. However, there is evidence of enhanced GSH levels in elderly subjects with excellent physical and mental health status, suggesting that heightened GSH may be a marker and even a causative factor of increased healthspan and lifespan. Such aspects, and much more including GSH-boosting substances administrable to humans, are considered in this state-of-the-art review, which deals with GSH and GSH-dependent enzymes from biochemistry to gerontology, focusing attention also on lifespan/healthspan extension and successful aging; the significance of GSH levels in aging is considered also in relation to therapeutic possibilities and supplementation strategies, based on the use of various compounds including NAC-glycine, aimed at increasing GSH and related defenses to improve health status and counteract aging processes in humans.

Evidence for oxidative and not reductive stress in the aged rabbit heart.

Reductive stress, which is due to a paradoxical excess of antioxidants such as reduced glutathione (GSH) and GSH-related enzymes associated with decreased oxidant levels, has emerged as a pathogenetic mechanism of myocardial damage in pathological conditions such as protein aggregation cardiomyopathy. Notably, in the aged heart a cardiomyopathy-like pathology occurs leading to myocardial dysfunction. Whether reductive stress, or instead its counterpart oxidative stress, is operative in the aged mammalian heart needs to be elucidated also for the different therapeutic implications of such redox stress conditions. In the present investigation, we assessed GSH and the specific enzymatic activities of γ-glutamylcysteine synthetase (γ-GCS), glutathione reductase (GSSG-Red) and selenium-dependent glutathione peroxidase (GSH-Px) as endogenous antioxidants, together with oxidized glutathione (GSSG) and the glutathione redox ratio (GSH/GSSG), in the aerobically perfused hearts of aged rabbits (about 4.5 years old) and young adult control rabbits (3-4 months old). We also assessed in the aged and control hearts H2O2 and catalytically active low molecular weight iron (LMWI) as oxidant forces, as well as fluorescent damage products of lipid peroxidation (FDPL) and protein carbonyls (PC) as biomarkers of lipid and protein oxidation. Moreover, the effects of 4.5 mM N-acetylcysteine (NAC) as reducing thiol antioxidant were studied on hemodynamic parameters and lipid peroxidation in the perfused hearts of the aged and control rabbits. The levels of GSH and of the GSH/GSSG ratio were lower, and those of GSSG higher, in the aged than in the control hearts. The aged hearts were also characterized by decreased activities of the antioxidant enzymes γ-GCS, GSSG-Red and GSH-Px, as well as by heightened levels of H2O2, LMWI, FDPL and PC, highlighting the occurrence of aging-dependent oxidative stress. Associated with such biochemical alterations, hemodynamic dysfunction occurred in the aged rabbit hearts, as evidenced by lowered developed pressure (DP) and enhanced end-diastolic pressure (EDP) with decreased coronary flow (CF). Remarkably, NAC administration significantly improved DP and EDP, and lowered lipid peroxidation, electively in the aged hearts. In conclusion, oxidative and not reductive stress is operative in the aged rabbit heart, whose hemodynamic dysfunction is improved by NAC together with reduction in myocardial lipid peroxidation.

Chromium and human low-density lipoprotein oxidation.

Chromium is a catalytic metal able to foster oxidant damage, albeit its capacity to induce human LDL oxidation is to date unkown. Thus, we have investigated whether trivalent and hexavalent chromium, namely Cr(III) and Cr(VI), can induce human LDL oxidation. Cr(III) as CrCl3 is incapable of inducing LDL oxidation at pH 7.4 or 4.5. However, Cr(III), specifically at physiological pH of 7.4 and in the presence of phosphates, causes an absorbance increase at 234 resembling a spectrophotometric kinetics of LDL oxidation with a lag- and propagation-like phase. In this regard, it is conceivable that peculiar Cr(III) forms such as Cr(III) hydroxide and, especially, Cr(III) polynuclear hydroxocomplexes formed at pH 7.4 interact with phosphates generating species with an intrinsic absorbance at 234 nm, which increases over time resembling a spectrophotometric kinetics of LDL oxidation. Cr(VI), as K2Cr2O7, can instead induce substantial human LDL oxidation at acidic pH such as 4.5, which is typical of the intracellular lysosomal compartment. LDL oxidation is related to binding of Cr(VI) to LDL particles with quenching of the LDL tryptophan fluorescence, and it is inhibited by the metal chelators EDTA and deferoxamine, as well as by the chain-breaking antioxidants butylated hydroxytoluene and probucol. Moreover, Cr(VI)-induced LDL oxidation is inhibited by mannitol conceivably by binding Cr(V) formed from LDL-dependent Cr(VI) reduction and not by scavenging hydroxyl radicals (OH); indeed, the OH scavengers sodium formate and ethanol are ineffective against Cr(VI)-induced LDL oxidation. Notably, heightened LDL lipid hydroperoxide levels and decreased LDL tryptophan fluorescence occur in Cr plating workers, indicating Cr-induced human LDL oxidation in vivo. The biochemical, pathophysiological and clinical implications of these novel findings on chromium and human LDL oxidation are discussed.

Impaired enzymatic reactive aldehyde-detoxifying capacity and glutathione peroxidase activity in the aged human arterial tissue.

It is not known whether aging alters the enzymatic reactive aldehyde- and lipid hydroperoxide-detoxifying capacity of the human arterial tissue favoring vascular oxidative stress. To address this issue, we studied the specific enzymatic activities of class 1, 2 and 3 aldehyde dehydrogenase (ALDH1, ALDH2 and ALDH3), glutathione S­transferase (isozyme A4-4, GSTA4-4) and aldose reductase (AR), namely the major reactive aldehyde-scavenging enzymes, together with the activity of the lipid hydroperoxide-removing enzyme glutathione peroxidase (GSH-Px), in superior thyroid arteries (STA) specimens obtained in the thyroid surgery setting in aged subjects (age 72.3 ±â€¯3.6 years) and young adult controls (age 31.9 ±â€¯3.5 years). Vascular lipid peroxidation was also studied by assessing in STA fluorescent damage products of lipid peroxidation (FDPL), which reflect oxidant-induced 4­hydroxynonenal and lipid hydroperoxide formation. Remarkably, the activities of ALDH1, ALDH2, ALDH3, GSTA4-4, AR and GSH-Px were significantly lower, and FDPL levels higher, in the arterial tissue of the aged subjects than in that of the young adult controls. Moreover, the enzymatic activities were inversely and significantly correlated with the levels of FDPL in the arterial tissue of both the aged and young subjects, highlighting their vascular antioxidant/antilipoperoxidative role in vivo. Thus, aging impairs the enzymatic reactive aldehyde-detoxifying capacity and GSH-Px activity of the human arterial tissue eventually favoring vascular oxidative stress.

Effects of topical vs injection treatment of cervical myofascial trigger points on headache symptoms in migraine patients: a retrospective analysis.

BACKGROUND: In migraine patients with cervical myofascial trigger points whose target areas coincide with migraine sites (M + cTrPs), TrP anesthetic injection reduces migraine symptoms, but the procedure often causes discomfort. This study evaluated if a topical TrP treatment with 3% nimesulide gel has similar efficacy as the injection but produces lesser discomfort with higher acceptability by the patients. METHODS: Retrospective analysis of medical charts of M + cTrPs patients in the period January 2012-December 2016 at a single Headache Center. Three groups of 25 patients each were included, all receiving migraine prophylaxis (flunarizine 5 mg/day) for 3 months and symptomatic treatment on demand. Group 1 received no TrP treatment, group 2 received TrP injections (bupivacaine 5 mg/ml at basis, 3rd, 10th, 30th and 60th day), group 3 received daily TrP topical treatment with 1.5 g of 3% nimesulide gel for 15 consecutive days, 15 days interruption and again 15 consecutive days. The following were evaluated: monthly number of migraine attacks and rescue medications, migraine intensity; pain thresholds to skin electrical stimulation (EPTs) and muscle pressure stimulation (PPTs) in TrP and target (basis, 30th, 60th and 180th days); discomfort from, acceptability of and willingness to repeat treatment (end of study). ANOVA for repeated measures and 1-way ANOVA were used to assess temporal trends in each group and comparisons among groups, respectively. Significance level was set at p < 0.05. RESULTS: Migraine improved over time in all groups, but significantly more and earlier in those receiving TrP treatment vs no TrP treatment (0.02 < p < 0.0001, 30-180 days for intensity and rescue medication, 60-180 days for number). All thresholds in the non-TrP-treated group did not change over time, while significantly improving in both the injection and nimesulide gel groups (0.01 < p < 0.0001, 30-180 days). Improvement of migraine and thresholds did not differ in the two TrP-treated groups. Discomfort was significantly lower, acceptability and willingness to repeat treatment significantly higher (0.05 < p < 0.0001) with gel than injection. CONCLUSION: In migraine patients, topical treatment of cervical TrPs with 5% nimesulide gel proves equally effective as TrP injection with local anesthetics but more acceptable by the patients. This treatment could be effectively associated to standard migraine prophylaxis to improve therapeutic outcomes.

Impaired glutathione-related antioxidant defenses in the arterial tissue of diabetic patients.

We studied the specific enzymatic activities of selenium-dependent (GSH-Px) and -independent (GST-Px) glutathione peroxidase, glutathione reductase (GSSG-Red), and glutathione S-transferase (GST) in internal mammary arteries (IMArt) specimens obtained during coronary artery bypass surgery in 18 patients with type 2 diabetes mellitus as compared to 18 non-diabetic controls; vascular lipid peroxidation, namely fluorescent damage products of lipid peroxidation (FDPL) as 4-hydroxynonenal-related oxidative stress indicators, was also studied. Moreover, in other 16 diabetic patients and 16 controls, total glutathione (TGlut) was determined in IMArt specimens specifically homogenized in sulfosalycilic acid to prevent vascular GSH depletion. The activities of GSH-Px, GSSG-Red, and GST were significantly lower, and FDPL levels higher, in the arterial tissue of diabetic patients than in that of controls; GST-Px was undetectable. Such enzymatic activities were inversely correlated with vascular lipid peroxidation, highlighting their antioxidant role in the arterial tissue, as were HbA1c and FDPL levels with the enzymatic activities, suggesting that glycation, oxidant species and lipoperoxidation aldehydes may be involved in glutathione-related enzyme inactivation. Further, in the diabetic patients HbA1c was correlated directly with lipid peroxidation but inversely with TGlut of the arterial tissue. In the patients considered for vascular enzymatic activities and FDPL assay, 3/4-vessel coronary artery disease (CAD) as expression of atherosclerosis severity was present in 9 diabetic patients and in 3 controls. Notably, vascular glutathione-related enzymatic activities were significantly lower, and FDPL levels higher, in the 9 diabetic patients with 3/4-vessel CAD than in the 9 without, as well as in the total of 12 patients with 3/4-vessel CAD than in the total of 24 patients without. Moreover, vascular TGlut content was significantly lower in the diabetic than in the control patients. Three/4-vessel CAD was present in 6 diabetic patients and in 2 controls considered for determination of vascular Tglut content, which was significantly lower in the diabetic patients with 3/4-vessel CAD than in those without, as well in the total of 8 patients with 3/4-vessel CAD than in the total of 24 patients without. Thus, weakened glutathione-related antioxidant capacity and oxidative stress of the arterial tissue are associated with the severity of atherosclerosis. In conclusion, impaired glutathione-related antioxidant defenses of the arterial tissue occur in diabetic patients, eventually favoring vascular oxidative stress and the severity of atherosclerosis.

Iron status and oxidative stress in the aged rabbit heart.

Altered iron status may be relevant to the pathophysiology of aging. We have assessed redox-active catalytic low molecular weight iron (LMWI), non-heme iron (NHI), heme iron (HI), and total iron (TI) in the aerobically perfused hearts of aged rabbits (AR, about 4.5years old) and young adult control rabbits (YACR, 3-4months old); myocardial lipid and protein oxidations were also assessed as oxidative stress biomarkers. The levels of LMWI and NHI, as well as of lipid and protein oxidation, were higher, while HI content was lower, in the hearts of AR than in those of YACR; TI did not differ significantly between the two groups. Together with these findings, hemodynamic dysfunction, namely heightened end-diastolic pressure (EDP) and lowered coronary flow (CF), occurred in the AR hearts. Notably, such pattern of hemodynamic dysfunction associated with myocardial oxidant damage occurred in the hearts of other YACR perfused in the presence of a cell-permeable form of iron, i.e., the iron/hydroxyquinoline complex, pointing to the involvement of catalytic iron in the aged heart damage. Moreover, as shown in other AR, heart perfusion in the presence of the iron chelator deferoxamine (0.6mM or 3.6mM) reduced the myocardial levels of LMWI, without significantly affecting those of NHI, HI, and TI; concomitantly, in AR deferoxamine lowered myocardial lipid and protein oxidation, and reduced EDP with a tendency to augment CF. Instead, deferoxamine, even at high concentration of 3.6mM, had no significant effects in the YACR. In conclusion, altered iron status with catalytic LMWI burden occurs in the aged rabbit heart, eventually resulting in iron-dependent cardiac oxidative stress and hemodynamic dysfunction.

Association of serum bilirubin with oxidant damage of human atherosclerotic plaques and the severity of atherosclerosis.

Bilirubin has protective effects against atherosclerotic cardiovascular diseases hypothetically due to its antioxidant-antilipoperoxidative properties. Thus, we investigated whether serum bilirubin is associated with oxidant damage, namely lipid peroxidation, of human atherosclerotic plaques and the severity of atherosclerosis. In this regard, we correlated the levels of serum total bilirubin (STB), direct (conjugated) bilirubin (SDB) and indirect (unconjugated) bilirubin (SIB) with those of fluorescent damage products of lipid peroxidation (FDPL) and lipid hydroperoxides (LOOH) of 32 endarterectomy-derived carotid atherosclerotic plaques. Moreover, we compared the levels of serum bilirubin and plaque lipoperoxides between two groups of patients of the study population with different severity of atherosclerosis as judged by the carotid stenosis degree, i.e., <90% (group A, n = 23) and ≥90% (group B, n = 9). Remarkably, the levels of STB were strongly inversely correlated with those of plaque FDPL (rS = -0.70, P < 0.0001) and LOOH (rS = -0.66, P < 0.0001), as were those of SIB (FDPL: rS = -0.68, P < 0.0001; LOOH: rS = -0.63, P < 0.0001). SDB had a weaker association with plaque FDPL (rS = -0.41, P < 0.05) and LOOH (rS = -0.35, P < 0.05). Moreover, the levels of STB, SDB and SIB were lower and those of plaque lipoperoxides higher in group B than in group A, pointing to the association of serum bilirubin and plaque oxidant burden with the severity of atherosclerosis. In conclusion, lowered serum bilirubin is associated with oxidant damage of human atherosclerotic plaques and the severity of atherosclerosis.

Iron as a catalyst of human low-density lipoprotein oxidation: Critical factors involved in its oxidant properties.

Iron-induced human LDL oxidation, which is relevant to atherosclerosis, has not yet been properly investigated. We addressed such issue using iron(II) and (III) basically in the presence of phosphates, which are present in vivo and influence iron oxidative properties, at pH 4.5 and 7.4, representative, respectively, of the lysosomal and plasma environment. In 10mM phosphate buffered saline (PBS), iron(II) induces substantial LDL oxidation at pH 4.5 at low micromolar concentrations, while at pH 7.4 has low oxidative effects; iron(III) promotes small LDL oxidation only at pH 4.5. In 10mM sodium acetate/NaCl buffer, pH 4.5, iron-induced LDL oxidation is far higher than in PBS, highlighting the relevance of phosphates in the inhibitory modulation of iron-induced LDL oxidation. LDL oxidation is related to iron binding to the protein and lipid moiety of LDL, and requires the presence of iron(II) bound to LDL together with iron(III). Chemical modification of LDL carboxyl groups, which could bind iron especially at pH 4.5, decreases significantly iron binding to LDL and iron-induced LDL oxidation. Hydroxyl radical scavengers are ineffective on iron-induced LDL oxidation, which is inhibited by metal chelation, scavengers of alkoxyl/peroxyl radicals, or removal of LDL lipid hydroperoxides (LOOH). Overall, substantial human LDL oxidation is induced LOOH-dependently by iron(II) at pH 4.5 even in the presence of phosphates, suggesting the occurrence of iron(II)-induced LDL oxidation in vivo within lysosomes, where pH is about 4.5, iron(II) and phosphates coexist, plasma with its antioxidants is absent, and glutathione peroxidase is poorly expressed resulting in LOOH accumulation.

Glutathione metabolic status in the aged rabbit aorta.

It is not known whether aging alters glutathione metabolic status of the mammalian arterial tissue favoring vascular oxidative stress and dysfunction. Thus we assessed total, reduced and oxidized glutathione (TG, GSH and GSSG, respectively), the glutathione redox ratio (GRR, namely [GSSG]/[GSH+2GSSG]×100), and the activities of the glutathione status-regulating enzymes glutathione reductase (GSSG-Red), γ-glutamylcysteine synthetase (γ-GCS) and γ-glutamyl transpeptidase (γ-GT) in the aortic tissue of 9 young adult control rabbits (YACR, about 4months old) and 9 aged rabbits (AR, about 4.5years old); aortic lipid and protein oxidation and H2O2 were also determined as oxidative stress indicators. Vascular function was assessed on aortic ring preparations. TG and GSH concentrations, together with γ-GCS and γ-GT activities, were significantly lower, while GSSG content and the GRR higher, in the AR than in the YACR aortas; GSSG-Red activity did not differ significantly between the two groups. Heightened levels of lipid and protein oxidation and H2O2 occurred in the AR aortas, indicating age-dependent vascular oxidative stress. Moreover, in the whole population of 18 rabbits, the aortic values of GSH and related enzyme activities were inversely and significantly correlated with those of lipid and protein oxidation and H2O2, highlighting the antioxidant role of GSH and related enzymes in the vascular tissue. Aortic endothelium-dependent vasodilation was lower in the AR than in the YACR. In conclusion, glutathione metabolic status is altered in the aged rabbit aorta reflecting depressed γ-GCS- and γ-GT-related GSH biosynthesis and GSSG burden eventually favoring vascular oxidative stress and dysfunction.

Use of Nonsteroidal Anti-Inflammatory Drugs for Symptomatic Treatment of Episodic Headache.

INTRODUCTION: Primary headaches have high epidemiologic impact but their symptomatic treatment often remains problematic. Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently used, but their modality of employment and efficacy/differential efficacy are highly variable. This study investigated current NSAID use for episodic headache at an Italian headache center (January 2000 to February 2013). METHODS: A retrospective evaluation was performed on 6,443 patient records: migraine (n = 2,330), tension-type headache (TTH; n = 807), and migraine plus TTH (n = 3,306). RESULTS: Among migraine patients, 80% had used NSAIDs in the past year. Preferences were: nimesulide (57%), ketoprofen (25%), and ibuprofen (24%); complete efficacy was significantly higher than incomplete/absent efficacy (P < 0.0001). NSAIDs were replaced with triptans in 53% of patients at first visit; after 1 year there was a spontaneous significant return to NSAIDs (56%; P < 0.0005). Among TTH patients, 90% were NSAID users; preferences were: nimesulide (48%), ketoprofen (47%), and diclofenac (19%), with significantly higher complete vs. incomplete/absent efficacy (nimesulide and ketoprofen, P < 0.02). Replacement with analgesics was performed in 24% of patients; after 1 year, there was a 29% return to NSAIDs. Among migraine plus TTH patients, 89% were NSAID users. Preferences were: nimesulide (44%), ibuprofen (42%), and ketoprofen (38%), with significantly higher complete vs. incomplete/absent efficacy (0.001 < P < 0.0001). Replacement with analgesics was performed in 31% of patients; after 1 year, there was a 37% return to NSAIDs. CONCLUSIONS: Nonsteroidal anti-inflammatory drug use in headache was higher than could be hypothesized based on guidelines, with NSAID preferences not entirely coinciding with international recommendations. This outcome suggests the need for greater awareness of all treatment options in headache by both patients and physicians.

Prognostic Value of Nondipping and Morning Surge in Elderly Treated Hypertensive Patients With Controlled Ambulatory Blood Pressure.

BACKGROUND: The independent prognostic significance of nondipping and morning surge (MS) of blood pressure (BP) in treated hypertensive patients with controlled ambulatory BP is not yet clear. We investigated the association between the aforesaid ambulatory BP parameters and cardiovascular risk in elderly treated hypertensive patients with normal achieved ambulatory BP. METHODS: The occurrence of a composite end-point (stroke, coronary events, heart failure, and peripheral revascularization) was evaluated in 391 elderly treated hypertensive patients (age range 60-90 years) with controlled ambulatory BP (both daytime BP <135/85 mm Hg and nighttime BP <120/70 mm Hg). According to nighttime change and MS of systolic BP, subjects were divided in dippers with normal or high MS (>23 mm Hg) and nondippers. RESULTS: During the follow-up (9.3 ± 4.6 years, range 0.5-20 years), 76 events occurred. The event-rate was 2.09 per 100 patient-years. After adjustment for age, gender, left ventricular (LV) hypertrophy, asymptomatic LV systolic dysfunction at baseline and left atrial enlargement, dippers with high MS (hazard ratio 2.45, 95% confidence interval 1.27-4.73, P = 0.007) and nondippers (hazard ratio 2.04, 95% confidence interval 1.18-3.53, P = 0.01) were at higher cardiovascular risk than dippers with normal MS. CONCLUSIONS: In elderly treated hypertensive patients with normal achieved ambulatory BP, dippers with high MS and nondippers are at increased cardiovascular risk.

Circadian blood pressure changes and cardiovascular risk in elderly-treated hypertensive patients.

The independent prognostic significance of circadian blood pressure (BP) changes is unclear. We investigated the association between circadian BP changes and cardiovascular risk among elderly-treated hypertensive patients. The occurrence of a composite end point (that is, stroke, coronary events, heart failure and peripheral revascularization) was evaluated among 1191 elderly-treated hypertensive patients (age range 60-90 years). According to the nighttime change and the morning surge (MS) of systolic BP, subjects were divided into groups of dippers with a normal or high MS (DNMS and DHMS, respectively), non-dippers (ND), reverse dippers (RD) and extreme dippers with a normal or high MS (EDNMS and EDHMS, respectively). During the follow-up (9.1±4.9 years, range 0.4-20 years), 392 events occurred. The event rate was 3.63 per 100 patient-years. After adjustment for various covariates, including 24-h BP, the DHMS (hazard ratio (HR) 1.49, 95% confidence interval (CI) 1.02-2.16, P=0.04), ND (HR 1.71, 95% CI 1.28-2.27, P=0.0001), RD (HR 2.05, 95% CI 1.44-2.93, P=0.0001) and EDHMS (HR 3.40, 95% CI 1.96-5.90, P=0.001) were at higher cardiovascular risk than the DNMS. The population attributable risk was 0.6, 7.1, 7.3 and 1.4% for the DHMS, ND, RD and EDHMS, respectively. In elderly-treated hypertensive patients, circadian BP changes were independently associated with increased cardiovascular risk. At the patient level, the highest risk was observed among the EDHMS, followed by the RD, ND and DHMS. At the population level, the highest risk was observed among the RD, followed by the ND, EDHMS and DHMS.

Ambulatory Blood Pressure Parameters and Heart Failure With Reduced or Preserved Ejection Fraction in Elderly Treated Hypertensive Patients.

BACKGROUND: The association between ambulatory blood pressure (BP) and future risk of heart failure (HF) is unclear. We investigated the association between ambulatory BP parameters and risk of HF with reduced ejection fraction (HFREF) or preserved ejection fraction (HFPEF) in elderly treated hypertensive patients. METHODS: The occurrence of HFREF and HFPEF was evaluated in 1,191 elderly treated hypertensive patients who underwent clinical and instrumental evaluation, including ambulatory BP monitoring to evaluate daytime, nighttime, and 24-hour BP, dipping status, and morning surge (MS) of BP. RESULTS: During the follow-up (9.1±4.9 years, range 0.4-20 years), 123 patients developed HF, of whom 56 had HFREF and 67 had HFPEF. After adjustment for other covariates, Cox regression analysis showed that 24-hour systolic BP, but not clinic BP, was independently associated with risk of both HFREF (hazard ratio (HR): 1.36, 95% confidence interval (CI): 1.14-1.63, per 10mm Hg increment) and HFPEF (HR: 1.35, 95% CI: 1.13-1.61, per 10mm Hg increment); moreover, high MS of BP (>23mm Hg) in dippers was independently associated with risk of HFREF (HR: 2.27, 95% CI: 1.00-5.15) and nondipping was independently associated with risk of HFPEF (HR: 2.78, 95% CI: 1.38-5.63). CONCLUSIONS: In elderly treated hypertensive patients, 24-hour systolic BP is independently associated with future risk of both HFREF and HFPEF, whereas high MS is independently associated with risk of HFREF and nondipping is independently associated with risk of HFPEF.

Ultramicronized palmitoylethanolamide reduces viscerovisceral hyperalgesia in a rat model of endometriosis plus ureteral calculosis: role of mast cells.

The effects of ultramicronized palmitoylethanolamide were evaluated on pain behaviours and markers of mast cell (MC) activity in a rat model of endometriosis plus ureteral calculosis (ENDO+STONE)-induced viscerovisceral hyperalgesia (VVH). Female Sprague-Dawley rats that underwent surgical induction of endometriosis were randomly assigned to receive active (ultramicronized palmitoylethanolamide 10 mg·kg(-1)·d(-1), orally) or placebo treatment for 25 days. At day 21, they underwent ureteral stone formation and were video-recorded till day 25 to evaluate ureteral and uterine pain behaviours. At autopsy (day 25), ureteral condition and number and diameter of endometrial cysts were evaluated. The following were then measured: number and percentage of degranulating MCs, number of vessels, chymase, nerve growth factor (NGF), vascular endothelial growth factor (VEGF), and Flk-1 (VEGF receptor) in cysts, and NGF in dorsal root ganglia (DRG). Ultramicronized palmitoylethanolamide-treated vs placebo-treated rats showed significantly lower number, duration and complexity of ureteral crises, shorter duration of uterine pain, and smaller cyst diameter (0.0001 < P < 0.004); a significantly higher percentage of expelled stones (P < 0.0001); significantly lower MC number (P < 0.01), vessel number (P < 0.01), chymase (P < 0.05), NGF (P < 0.05), VEGF (P < 0.01), and Flk-1 (P < 0.01) expression in cysts and NGF expression in DRG (P < 0.01). In all animals, the global duration of ureteral crises correlated linearly and directly with cyst diameter, MC number and chymase in cysts, and NGF in cysts and DRG (0.02 < P < 0.0002). Ultramicronized palmitoylethanolamide significantly reduces VVH from ENDO+STONE, probably by modulating MC expression/activity in cysts, thus reducing central sensitization due to noxious signals from endometriotic lesions. The results suggest potential utility of the compound for VVH in clinics.

Reactive aldehyde-scavenging enzyme activities in atherosclerotic plaques of cigarette smokers and nonsmokers.

OBJECTIVE: To investigate enzymatic reactive aldehyde-scavenging enzyme capacity together with lipid peroxidation as expression of oxidative stress in atherosclerotic plaques of cigarette smokers and nonsmokers. METHODS: We have assessed specific enzymatic activities of class 1, 2, and 3 aldehyde dehydrogenase (ALDH1, ALDH2, and ALDH3, respectively), glutathione S-transferase (isozyme A4-4, GSTA4-4), and aldose reductase (AR), namely the major reactive aldehyde-scavenging enzymes, together with lipid peroxidation, i.e., fluorescent damage products of lipid peroxidation (FDPL), in carotid atherosclerotic plaques surgically removed from 17 cigarette smokers and 17 nonsmokers. RESULTS: The enzymatic activities of ALDH1 plus ALDH2, ALDH3, GSTA4-4, and AR were significantly lower in the atherosclerotic plaques of smokers than in those of nonsmokers, while plaque FDPL levels were significantly higher in the smokers than in the nonsmokers. The amount of cigarette smoking was correlated inversely with the aforementioned plaque enzymatic activities and directly with plaque FDPL content. Plaque FDPL levels were inversely correlated with plaque enzymatic activities in smokers and nonsmokers. The degree of carotid atherosclerotic stenosis, as expression of atherosclerosis severity, was correlated inversely with plaque enzymatic activities and directly with plaque FDPL levels in smokers and nonsmokers; moreover, the degree of carotid stenosis was directly correlated with the amount of cigarette smoking. CONCLUSION: atherosclerotic lesions of cigarette smokers are endowed with a depressed enzymatic reactive aldehyde-scavenging capacity eventually favoring oxidative stress and the severity of atherosclerosis.

Effects of topical diclofenac plus heparin (DHEP+H plaster) on somatic pain sensitivity in healthy subjects with a latent algogenic condition of the lower limb.

OBJECTIVE: To evaluate whether a diclofenac epolamine + heparin topical (plaster) is more effective than diclofenac plaster alone in reducing deep somatic hyperalgesia in subjects without spontaneous pain and whether the effect is linked to or independent of the anti-edematous action of heparin. DESIGN: Prospective, double-blind, randomized and controlled, four-arm parallel design trial. SUBJECTS: One hundred and four patients (84 women, 20 men, mean age 42.2 ± 13.3 years), with deep somatic hyperalgesia in one thigh, randomly assigned to one of 4 groups of 26 each. INTERVENTION: Each group underwent one of the following plaster treatments on one thigh: diclofenac+heparin; diclofenac; heparin; placebo, for 7 days, renewing the plaster every 24 hours. OUTCOME MEASURES: Before treatment (day 1), at day 4 and day 8, assessment of (a) pressure and electrical pain thresholds of vastus lateralis and overlying subcutis and skin; and (b) structure/thickness of subcutis and muscle with ultrasounds at the same level. RESULTS: During treatment, in placebo and heparin, no significant threshold changes, except subcutis thresholds which increased slightly (P < 0.02); in diclofenac and diclofenac+heparin, significant increase in all thresholds (0.0001 < P < 0.04). Electrical muscle pain thresholds increased significantly more in diclofenac+heparin than in diclofenac, heparin, and placebo (0.0001 < P < 0.04). In all groups: no edema and thickness changes at ultrasounds in muscle and subcutis. CONCLUSIONS: Topical diclofenac+heparin is significantly more effective than diclofenac alone in reducing muscle hyperalgesia in subjects without spontaneous pain, independently of the anti-edematous action of heparin. The results provide a rationale for the use of diclofenac+heparin also in algogenic conditions without evident signs of injury/edema/hematoma.

Oxidative stress-related mechanisms affecting response to aspirin in diabetes mellitus.

Type 2 diabetes mellitus (T2DM) is a major cardiovascular risk factor. Persistent platelet activation plays a key role in atherothrombosis in T2DM. However, current antiplatelet treatments appear less effective in T2DM patients vs nondiabetics at similar risk. A large body of evidence supports the contention that oxidative stress, which characterizes DM, may be responsible, at least in part, for less-than-expected response to aspirin, with multiple mechanisms acting at several levels. This review discusses the pathophysiological mechanisms related to oxidative stress and contributing to suboptimal aspirin action or responsiveness. These include: (1) mechanisms counteracting the antiplatelet effect of aspirin, such as reduced platelet sensitivity to the antiaggregating effects of NO, due to high-glucose-mediated oxidative stress; (2) mechanisms interfering with COX acetylation especially at the platelet level, e.g., lipid hydroperoxide-dependent impaired acetylating effects of aspirin; (3) mechanisms favoring platelet priming (lipid hydroperoxides) or activation (F2-isoprostanes, acting as partial agonists of thromboxane receptor), or aldose-reductase pathway-mediated oxidative stress, leading to enhanced platelet thromboxane A2 generation or thromboxane receptor activation; (4) mechanisms favoring platelet recruitment, such as aspirin-induced platelet isoprostane formation; (5) modulation of megakaryocyte generation and thrombopoiesis by oxidative HO-1 inhibition; and (6) aspirin-iron interactions, eventually resulting in impaired pharmacological activity of aspirin, lipoperoxide burden, and enhanced generation of hydroxyl radicals capable of promoting protein kinase C activation and platelet aggregation. Acknowledgment of oxidative stress as a major contributor, not only of vascular complications, but also of suboptimal response to antiplatelet agents in T2DM, may open the way to designing and testing novel antithrombotic strategies, specifically targeting oxidative stress-mediated mechanisms of less-than-expected response to aspirin.