Pierluigi Pompei

Diaphragmatic Breathing Reduces Exercise-Induced Oxidative Stress

Diaphragmatic breathing is relaxing and therapeutic, reduces stress, and is a fundamental procedure of Pranayama Yoga, Zen, transcendental meditation and other meditation practices. Analysis of oxidative stress levels in people who meditate indicated that meditation correlates with lower oxidative stress levels, lower cortisol levels and higher melatonin levels. It is known that cortisol inhibits enzymes responsible for the antioxidant activity of cells and that melatonin is a strong antioxidant; therefore, in this study, we investigated the effects of diaphragmatic breathing on exercise-induced oxidative stress and the putative role of cortisol and melatonin hormones in this stress pathway. We monitored 16 athletes during an exhaustive training session. After the exercise, athletes were divided in two equivalent groups of eight subjects. Subjects of the studied group spent 1 h relaxing performing diaphragmatic breathing and concentrating on their breath in a quiet place. The other eight subjects, representing the control group, spent the same time sitting in an equivalent quite place. Results demonstrate that relaxation induced by diaphragmatic breathing increases the antioxidant defense status in athletes after exhaustive exercise. These effects correlate with the concomitant decrease in cortisol and the increase in melatonin. The consequence is a lower level of oxidative stress, which suggests that an appropriate diaphragmatic breathing could protect athletes from long-term adverse effects of free radicals.

Effects of adrenal steroids on basal ganglia neuropeptide mRNA and tyrosine hydroxylase radioimmunoreactive levels in the adrenalectomized rat.

Abstract: To investigate the effects of type I (mineralocorticoid) and type II (glucocorticoid) receptor activation on striatal neuropeptide [preproenkephalin (PPE), preprotachykinin (PPT), and preprodynorphin (DYN)] mRNA and midbrain cholecystokinin (CCK) mRNA as well as striatal tyrosine hydroxylase radioimmunoreactivity (TH‐RIC) levels, we administered either replacement levels of corticosterone (CORT; 0.5 mg/kg/day, s.c.) or pharmacological levels of deoxycorticosterone acetate (DOCA; a mineralocorticoid steroid with ability to bind to type I and type II receptors; 5 mg/kg, s.c.) to adrenalectomized adult male rats. After 1 week of recovery from adrenalectomy surgery, animals were injected daily with sesame oil or CORT for 1, 3, or 7 days or DOCA for 3 or 7 days and killed 16 h after the last injection. Adrenalectomy resulted in a decrease in all three striatal neuropeptide mRNA levels, compared with sham‐operated rats. CORT replacement resulted in recovered PPE and PPT mRNA levels after 1 day and elevated PPE mRNA levels over those in sham‐operated controls after 3 days. In contrast, DYN mRNA levels showed recovery after 7 days of CORT replacement. Results after DOCA treatment largely paralleled those after CORT replacement. There were no significant treatment effects on indirect markers of midbrain dopaminergic activity, i.e., CCK mRNA and TH‐RIC. From these results we conclude that compared with striatal tachykinin and dynorphinergic neurons, enkephalinergic cells show greater sensitivity, whereas the dopaminergic system, including mesencephalic CCK, demonstrates an insensitivity to physiological CORT and to pharmacological DOCA treatment.

Mebendazole inhibits growth of human adrenocortical carcinoma cell lines implanted in nude mice

Adrenocortical carcinoma is a rare tumor of the adrenal gland which requires new therapeutic approaches as its early diagnosis is difficult and prognosis poor despite therapies used. Recently, mebendazole has been proved to be effective against different cancers. The aim of our study was to evaluate whether mebendazole may result therapeutically useful in the treatment of human adrenocortical carcinoma. We analyzed the effect of mebendazole on human adrenocortical carcinoma cells in vitro and after implantation in nude mice. In order to clarify mechanisms of mebendazole action, metastases formation, apoptosis and angiogenesis were also investigated. Mebendazole significantly inhibited cancer cells growth, both in vitro and in vivo, the effects being due to the induction of apoptosis. Moreover, mebendazole inhibited invasion and migration of cancer cells in vitro, and metastases formation in vivo. Overall, these data suggest that treatment with mebendazole, also in combination with standard therapies, could provide a new protocol for the inhibition of adrenocortical carcinoma growth.

Salt Appetite in Salt-Replete Rats: Involvement of Mesolimbic Structures in Deoxycorticosterone-Induced Salt Craving Behavior

Chronic administration of the mineralocorticoid deoxycorticosterone acetate (DOCA) induces a steady and robust increase in salt appetite and plasma Na+ over the course of treatment. Interestingly, salt appetite behavior persists in rats even with elevated plasma Na+ levels. Since there is evidence that the pathways normally associated with salt and water homeostasis are relatively unaffected in the DOCA-treated rat, we hypothesized that other regulatory systems may be hyperactive giving rise to this dysfunctional condition. The mesolimbic dopaminergic system has long been associated with orienting and reward-seeking behaviors such as those observed in reproduction, drug abuse, and appetite. Furthermore, we have previously shown that chronic DOCA administration results in an increase in mRNA levels of the endogenous opiate enkephalin in male rats given 24-hour access to tap water and 2% NaCl (two-bottle choice). Thus, in the present study, we tested the hypothesis that the mesolimbic dopaminergic system is dysfunctionally sensitized to the presence of a salt stimulus in DOCA-treated animals. Four groups of rats were injected with DOCA (5 mg/rat/day, 11 days) and one with vehicle (all were given access to water but access to salt was regulated). Two DOCA groups were given 2 h of 2% NaCl access/day and on the last day, one group was not given access (2hX). One of the two remaining DOCA groups was given 24-hour access to salt (24h) and the other no access at all (24hX). Consistent with our hypothesis, in the shell of the nucleus accumbens (AcbSh) we found relatively higher enkephalin- and tachykinin-mRNA abundance in the 2h vs. 2hX and dynorphin-mRNA in the 24h vs. 24hX groups. In addition, there were decreases in dopamine transporter binding in the AcbSh and decreases in tyrosine hydroxylase immunoreactivity throughout the striatum in the 24h vs. 24hX group. Furthermore, rats denied access to salt (2hX and 24hX) had higher cholecystokinin-mRNA levels in the ventral tegmental area compared to the 2h and 24h groups, respectively. These results suggest that basal ganglia structures associated with reward and goal-seeking behavior may be activated to elicit salt craving behavior in the DOCA-induced salt-appetitive rat.

5-HT2 receptor antagonists do not reduce ethanol preference in Sardinian alcohol-preferring (sP) rats

The present study investigated the effect of the 5-HT2/1C receptor antagonist ritanserin, and of the 5-HT2/D2 receptor antagonist risperidone on ethanol preference in Sardinian alcohol-preferring (sP) rats. Rats were offered free access to both tap water and 8% (in one experiment 3%) ethanol solution. Subchronic (10 or 1 mg/kg/day, for 10 days) or chronic (1 mg/kg/day, for 30 days) subcutaneous (SC) ritanserin treatment failed to reduce 8% ethanol preference. Risperidone doses that produce marked 5-HT2, but low dopamine D2, receptor blockade (1 and 0.1 mg/kg/day, SC, for 9 and 10 days, respectively) did not modify 8% ethanol preference. On the other hand, a high risperidone dose (10 mg/kg/day, SC, for 14 days), which produces pronounced dopamine D2 receptor blockade, reduced 8% ethanol preference, like the dopamine receptor antagonist haloperidol. Previous studies have shown that both ritanserin and risperidone evoke long-lasting and pronounced suppression of 3% ethanol preference in genetically nonselected rats. However, in the present study, SC ritanserin treatment (1 mg/kg/day for 10 days) did not modify 3% ethanol preference in sP rats. The failure of 5-HT2 antagonists to reduce ethanol preference in sP rats raises the question whether genetic selection might have resulted in altered regulation of 5-HTergic mechanisms in sP rats.

Memory impairment following combined exposure to Δ9-tetrahydrocannabinol and ethanol in rats

Abstract Cannabis derivatives and alcohol are widely co-abused, particularly among adolescents. Since both ethanol and cannabinoids are known to impair learning and memory, the present study investigated in rats the effects of combined exposure to ethanol and Δ9-tetrahydrocannabinol (THC) in a memory task, the object recognition test. The results of the present study provide evidence that ethanol, voluntarily ingested in alcohol-preferring rats, and THC, given by intraperitoneal injection, have a synergic action to impair object recognition, when a 15-min interval was adopted between the sample phase and the choice phase of the test. Neither voluntary ethanol ingestion nor 2 or 5 mg/kg of THC were able per se to modify object recognition in these experimental conditions, but when voluntary ethanol ingestion was combined with administration of these doses of THC object recognition was markedly impaired. THC impaired object recognition only at the dose of 10 mg/kg, when its administration was not combined with that of ethanol. The selective cannabinoid CB1 receptor antagonist SR 141716A (N-(piperidin-1-yl)-5-(4-chlorophenyl)-1(2, 4-dichloro-phenyl)-4-methyl-1H-pyrazole carboxamide·HCl) at the dose of 1 mg/kg reversed the amnesic effect of THC, 10 mg/kg, suggesting that the effect is mediated by this receptor subtype. The synergism of ethanol and THC was not detected when an inter-trial interval of 1 min was adopted. The present findings are in keeping with the notion that Cannabis derivatives impair memory processes and provide evidence for a synergic action of THC and ethanol, thus emphasizing the risks consequent to their co-administration.

Selective agonists at NK3 tachykinin receptors inhibit alcohol intake in sardinian alcohol-preferring rats

The present study evaluated the effect of tachykinin agonists, selective for different neurokinin (NK) receptors, on alcohol intake in genetically selected, Sardinian alcohol-preferring rats. Tachykinins were given by intracerebroventricular injection just before access to fluids. In rats offered both water and 8% ethanol 2 h/day, the NK3 selective agonists [Asp5.6,MePhe8]substance P(5-11), Suc[Asp6,MePhe8]substance P(6-11), and [MePhe7]neurokinin B markedly suppressed alcohol intake. The NK1 selective agonist [Sar9,Met(O2)11]substance P and the NK2 selective agonist GR 64349 did not At doses that inhibited alcohol intake, the NK3 agonists did not modify water intake; total fluid intake was significantly reduced only following 500 ng/rat of [Asp5.6,MePhe8]substance P(5-11). When rats were given a longer access to fluids (8% alcohol for 2 h, but water for 4 h), again, NK3 agonists suppressed alcohol intake, but not total fluid intake. Moreover, NK3 agonists did not modify solid food intake in food-deprived rats, nor water intake in water-deprived rats, when alcohol was not available. These findings indicate that NK3 agonists inhibit alcohol intake in Sardinian alcohol-preferring rats and that their effect is behaviorally selective. They also suggest that central NK3 receptors may be involved in alcohol intake control in rats.

Suppression of alcohol preference in rats induced by risperidone, a serotonin 5-HT2 and dopamine D2 receptor antagonist

The present study investigated the effect of the 5-HT2 and dopamine D2 receptor antagonist risperidone on alcohol preference in the rat. Rats with developed preference for 3% ethanol were injected subcutaneously (SC) with 10, 1, or 0.1 mg/kg of risperidone for 7, 10, and 10 days, respectively. Risperidone (10 mg/kg) evoked an inhibitory effect on alcohol preference similar (rapid onset, but short duration) to that observed after treatment with the dopamine D2 receptor antagonist haloperidol, 0.0625 mg/kg, SC. The lowest dose of risperidone (0.1 mg/kg) evoked marked inhibition of ethanol drinking, similar (slow onset, but long-lasting effect) to that produced by the 5-HT2 receptor antagonist ritanserin, 1 mg/kg, SC. Present results demonstrate that risperidone suppresses alcohol preference in the rat and suggest that its effect, depending on the dose, might involve different neurochemical mechanisms (mainly dopaminergic at high doses and mainly serotonergic at low doses). The results obtained with the lowest dose of risperidone (0.1 mg/kg), at which the drug is rather selective for 5-HT2 receptors, are in keeping with previous findings obtained with ritanserin and support the hypothesis that 5-HT2 receptor blockade reduces alcohol intake in rats.

The 5-HT4 receptor antagonist, GR113808, reduces ethanol intake in alcohol-preferring rats

The present study evaluated the effect of the selective 5-HT4 receptor antagonist, GR113808, on ethanol intake in alcohol-preferring rats. Rats were offered 10% ethanol 2 h/day. In the first experiment, rats had food and water ad lib and 10% ethanol was offered from 1800 to 2000 h. In the second experiment, food was freely available, 10% ethanol was offered 2 h/day, from 1800 to 2000 h, and water was offered for 4 h, from 1800 to 2200 h. In both experiments GR113808 was subcutaneously injected at doses of 1, 3, or 10 mg/kg for 4 consecutive days, 5 min before access to ethanol. From the first day of administration, GR113808 significantly reduced the volitional ethanol intake in water sated rats at the three doses tested. In water-deprived rats, it reduced ethanol intake at 3 and 10 mg/kg, without modifying total fluid and food intake. In both experiments the effect of GR113808 remained rather stable during the 4 days of administration. The present findings, showing that the 5-HT4 receptor antagonist, GR113808, selectively reduces ethanol intake in alcohol-preferring rats, suggest that 5-HT4 receptors may play a role in alcohol intake control.

Doxazosin-related alpha1-adrenoceptor antagonists with prostate antitumor activity.

Doxazosin analogues 1-3 and 1a were synthesized and investigated at alpha1-adrenoceptors and PC-3, DU-145, and LNCaP human prostate cancer cells. Compound 1 (cyclodoxazosin) was a potent alpha(1B)-adrenoceptor antagonist displaying antiproliferative activity higher than that of doxazosin in cancer cells in vitro and in vivo, respectively. Because of its antitumor efficacy at low concentrations, lower apoptotic activity in NHDF vs tumor cells, and antiangiogenetic effect, 1 showed a better therapeutic profile relative to doxazosin.