Hypericum perforatum attenuates nicotine withdrawal signs in mice

Sintocalmy, a Passiflora incarnata Based Herbal, Attenuates Morphine Withdrawal in Mice

Chronic opioid use changes brain chemistry in areas related to reward processes, memory, decision-making, and addiction. Both neurons and astrocytes are affected, ultimately leading to dependence. Passiflora incarnata L. (Passifloraceae) is the basis of frequently used herbals to manage anxiety and insomnia, with proven central nervous system depressant effects. Anti-addiction properties of P. incarnata have been reported. The aim of this study was to investigate the effect of a commercial extract of Passiflora incarnata (Sintocalmy®, Aché Laboratory) in the naloxone-induced jumping mice model of morphine withdrawal. In addition, glial fibrillary acidic protein (GFAP) and S100 calcium-binding protein B (S100B) levels were assessed in the frontal cortex and hippocampus, and DNA damage was verified on blood cells. In order to improve solubilization a Sintocalmy methanol extract (SME) was used. SME is mainly composed by flavonoids isovitexin and vitexin. The effects of SME 50, 100 and 200 mg/kg (i.p.) were evaluated in the naloxone-induced withdrawal syndrome in mice. SME 50 and SME 100 mg/kg decreased naloxone-induced jumping in morphine-dependent mice without reducing locomotor activity. No alterations were found in GFAP levels, however SME 50 mg/kg prevented the S100B increase in the frontal cortex and DNA damage. This study shows anti-addiction effects for a commercial standardized extract of P. incarnata and suggests the relevance of proper clinical assessment.

Randomized Clinical Trials Investigating Innovative Interventions for Smoking Cessation in the Last Decade

Every year, billions of dollars are spent treating smoking and related conditions, yet smoking-related morbidity and mortality continue to rise. There are currently only three FDA-approved medications for smoking cessation: nicotine replacement therapy, bupropion, and varenicline. Although these medications increase abstinence rates, most individuals relapse following treatment. This chapter reviews clinical trials published within the past 10 years investigating novel smoking cessation pharmacotherapies. Among these pharmacotherapies, some showed promising results, such as cytisine and endocannabinoid modulators, whereas others failed to produce significant effects. More research is needed to develop drugs that produce higher rates of long-term abstinence and to determine which subgroups of patients benefit from a given treatment.

The role of cultural interaction in Tianeptine Abuse and Different Tianeptine Application Methods

Tianeptine is a selective serotonin reuptake enhancer, possessing strong antidepressant and anxiolytic properties. Its relative lack of sedative, anticholinergic and cardiovascular side effects makes it a highly tolerable substance of abuse. However, physical dependence quickly develops and withdrawal symptoms are common. Abusers in Georgia and Armenia use tianeptine by intravenous injection. Drug abusing behaviour usually starts during puberty, since it stems from psychological, social and cultural circumstances. Sociodemographic studies show that drug abusing behaviour in Turkey varies according to region and substance. This paper investigates differences between Georgian foreigners and the local population in the eastern Black Sea region in terms of tianeptine abuse and discusses complications resulting from intravenous injection of tiapentine.

Evaluation of Rhodiola rosea L. extract on affective and physical signs of nicotine withdrawal in mice

The aim of the present study was to investigate the effects of a Rhodiola rosea L. extract on the prevention of the development of nicotine dependence and for the reduction of abstinence suffering following nicotine cessation in mice. Dependence was induced in mice by subcutaneous injections of nicotine (2 mg/kg, 4 times/day) for eight days. Spontaneous abstinence syndrome was evaluated 20 h after the last nicotine administration, by analysis of withdrawal signs, as affective (anxiety-like behaviour) and physical (somatic signs and locomotor activity). Rhodiola rosea L. extract was administered orally during nicotine treatment (10, 15 and 20 mg/kg) or during nicotine withdrawal (20 mg/kg). Results show that both affective and somatic signs (head shaking, paw tremors, body tremors, ptosis, jumping, piloerection and chewing) induced by nicotine withdrawal are abolished by administration of Rhodiola rosea L. extract in a dose-dependent fashion, during both nicotine exposure and nicotine cessation. In conclusion, our data encourage additional studies to define the use of R. rosea L. as a therapeutic approach in the treatment of smoking cessation.

Interactions between endocannabinoid and serotonergic systems in mood disorders caused by nicotine withdrawal

INTRODUCTION

Endocannabinoid and serotonin systems are implicated in mechanisms underlying depression-like symptoms. Involvement of serotonin in mood disorders occurring after smoking cessation has been observed. We studied the interactions between endocannabinoid and serotonergic systems in mood and behavioral disorders caused by nicotine cessation. The effects of the endocannabinoid transport inhibitor AM404 and the cannabinoid receptor 1 antagonist AM251 in a nicotine-dependent rodent model were investigated.

METHODS

Dependence was induced by subcutaneous injections of nicotine (2 mg/kg, 4 injections daily) for 15 consecutive days in mice. Animals treated with AM404 or AM251 were tested for locomotor activity and abstinence signs 24 hr after nicotine withdrawal and in forced swimming test (FST) at different times: immediately after last nicotine injection (t = 0) and 15 and 30 days after nicotine withdrawal. In nicotine-dependent mice treated with AM404 or AM251, expression of diencephalic serotonin receptor 1(A) (5-HT1(A)) was also measured. Effects of AM404, AM251, and WAY 100635 (5-HT(1A) receptor antagonist) in mice subjected to FST were evaluated.

RESULTS

A decrease in diencephalic 5-HT(1A) levels was observed in mice previously injected with nicotine. In the same animals, AM251 caused (0.5-2 mg/kg) a significant decrease of abstinence signs and AM404 (0.5-2 mg/kg) provoked a significant dose-dependent reduction in immobility time in the FST. Either AM251 or WAY 100635 antagonized anti-immobility effects of AM404.

CONCLUSIONS

Data indicate the existence of a link between serotonergic and endocannabinoid systems in the mechanisms underlying mood disorders caused by nicotine abstinence and suggest that these interactions are potential targets for pharmacological aid in smoking cessation.

A randomized clinical trial of St. John's wort for smoking cessation

INTRODUCTION

St. John's wort (SJW) is a widely used herbal supplement. The predominant mechanism(s) accounting for the activity of SJW in vivo are, however, unclear. The purpose of this study was to investigate the efficacy of SJW for smoking cessation.

METHODS

We conducted a randomized, blinded, placebo-controlled, three-arm, dose-ranging clinical trial. A total of 118 subjects were randomly allocated to receive SJW 300 mg, 600 mg, or a matching placebo tablet 3 times a day combined with a behavioral intervention for 12 weeks. Self-reported smoking abstinence was biochemically confirmed with expired air carbon monoxide.

RESULTS

Mean age of the study participants was 37.6 +/- 12.4 years; they smoked an average of 20.0 +/- 6.6 cigarettes per day for 20 +/- 12.1 years. The study dropout rate was high (43%). By intention-to-treat analysis, no significant differences were observed in abstinence rates at 12 and 24 weeks between SJW dose groups and placebo. SJW did not attenuate withdrawal symptoms among abstinent subjects. Abstinence rates did not differ by study group among subjects who took at least 75% of their study medication. No significant side-effects were noted with SJW.

CONCLUSIONS

In this randomized trial, SJW did not increase smoking abstinence rates. Our data, in combination with data from other studies, suggest that SJW has little role in the treatment of tobacco dependence.

A proof of concept randomised placebo controlled factorial trial to examine the efficacy of St John's wort for smoking cessation and chromium to prevent weight gain on smoking cessation

BACKGROUND

St John's wort is an effective antidepressant that can reduce tobacco withdrawal symptoms, but it is not known whether it assists cessation. Chromium assists weight loss and might limit post cessation weight gain.

METHODS

In a factorial design, we randomised smokers stopping smoking to 900 mg St John's wort (SJW) active or placebo and also randomised them to 400 microm chromium or placebo daily. Treatment started 2 weeks prior to quit day and continued for 14 weeks. Participants and researchers were blind to treatment allocation. All participants received weekly behavioural support. The primary endpoints were biochemically confirmed prolonged abstinence and mean weight gain in abstinent smokers 4 weeks after quitting.

RESULTS

6/71 (8.5%) participants on active SJW and 9/72 (12.5%) on placebo achieved prolonged abstinence at 4 weeks, an odds ratio (OR) (95% confidence interval) of 0.65 (0.22-1.92). At 6 months, 3 (4.2%) SJW active and 6 (8.3%) SJW placebo participants were still abstinent, an OR of 0.49 (0.12-2.02). Among these participants, the mean difference in weight gain between active chromium and placebo was -0.8 1kg (-3.79 to 2.18) at 4 weeks and -3.88 kg (-12.13 to 4.38) at 6 months.

CONCLUSIONS

Taking together the absolute quit rates, the small difference between active and placebo, and lack of effects on withdrawal shows that SJW is ineffective for smoking cessation. Insufficient people stopped smoking to properly test the efficacy of chromium in preventing weight gain, but the point estimate indicates a potentially worthwhile benefit.

Rodent models of nicotine withdrawal syndrome

Simple, rapid and inexpensive rodent models of nicotine physical dependence and withdrawal syndrome have proved useful for preliminary screening of smoking cessation treatments. They have led to an exponential increase of knowledge regarding the underlying neurobiological mechanisms of dependence and withdrawal syndrome. The human nicotine withdrawal syndrome in smoking cessation is variable and multidimensional, involving irritability, anxiety, depression, cognitive and attentional impairments, weight gain, sleep disturbances, and craving for nicotine. Aside from sleep disturbances, analogous phenomena have been seen in rodent models using different measures of withdrawal intensity. It appears likely that different withdrawal phenomena may involve some partially divergent mechanisms. For example, depression-like phenomena may involve alterations in mechanisms such as the mesolimbic dopamine pathway from the ventral tegmental area to the nucleus accumbens. Irritability and anxiety may involve alterations in endogenous opioid systems and other regions, such as the amygdala. This chapter reviews many additional anatomical, neurochemical, and developmental elements that impact nicotine physical dependence.

Serotonin mediates beneficial effects of Hypericum perforatum on nicotine withdrawal signs

Antidepressants may be effective treatment for smoking cessation and new evidence on relationship between smoking and depression is emerging. Extracts of the plant Hypericum perforatum possess antidepressant activity in humans and reduce nicotine withdrawal signs in mice. Both nicotine and H. perforatum administration elicit changes in serotonin (5-HT) formation in the brain. On this basis, we investigated the possible involvement of 5-HT in the beneficial effects of H. perforatum on nicotine withdrawal signs. With the aim to induce nicotine dependence, nicotine (2 mg/kg, four intraperitoneal injections daily) was administered for 14 days to mice (NM). Saline (controls, M) or H. perforatum extract (Ph 50, 500 mg/kg) were orally administered immediately after the last nicotine injection for 30 days after nicotine withdrawal. Another group of animals treated with nicotine (14 days) and successively with H. perforatum extract was intraperitoneally co-administered with selective 5-HT receptorial antagonist WAY 100635 (WAY) (1 mg/kg). All animals were evaluated for locomotor activity and abstinence signs, 24 after nicotine withdrawal. Brain 5-HT metabolism was evaluated in the cortex of mice sacrificed 30 days after nicotine withdrawal through evaluation of 5-HT, 5-hydroxyindoleacetic acid (5-HIAA) and 5-HIAA/5-HT ratio. After nicotine withdrawal measurement of 5-HT metabolism in the cortex showed a reduction of 5-HT content while animals treated only with Hypericum extract showed a significant reduction of total abstinence score compared to controls. WAY inhibited the reduction of total abstinence score induced by H. perforatum. Moreover, 5-HT1A expression has been evaluated 30 days after nicotine withdrawal. Our results, show a significant increase of cortical 5-HT content in NM treated with H. perforatum, with a concomitant significant increase of 5-HT1A receptor. So, it is possible to suggest an involvement of 5-HT in beneficial effects of H. perforatum on suffering produced by nicotine withdrawal in dependent mice.

Extract of Hypericum perforatum blocks caffeine-induced locomotor activity in mice: a possible role of nitric oxide

The present study investigated the effects of HPE on caffeine-induced locomotor activity in mice. Caffeine (4-16 mg/kg) or saline were given to adult male Swiss-Webster mice, and the locomotor activity was immediately measured for 30 min. HPE (6-48 mg/kg) and saline were injected to another group of mice and the locomotor activity was measured 20 min later. HPE (6-24 mg/kg) was also administered to another group of mice 20 min before caffeine (16 mg/kg) injections and the locomotor activity was recorded for 30 min immediately after caffeine administrations. Finally l-arginine (1 g/kg) was administered i.p. 20 min before HPE (6 mg/kg) and the locomotor activity was measured as mentioned above. Each group of mice was used only once. Caffeine produced some significant increases in locomotor activity of the mice. HPE (6-24 mg/kg) significantly blocked the caffeine-induced locomotor hyperactivity. Pretreatment of l-arginine (1 g/kg) reversed the inhibitory effect of HPE (6 mg/kg) on caffeine-induced locomotor activity without producing any significant effect on locomotor activity of the mice when it was administered alone. The results suggest that HPE blocks caffeine-induced locomotor hyperactivity in mice. Furthermore, the inhibitory effect of HPE on caffeine-induced locomotor activity may be related to its NOS inhibitory property.

A Phase II study of St. John's Wort for smoking cessation

OBJECTIVES

To examine the feasibility and efficacy of St. John's Wort (SJW) for smoking cessation.

DESIGN

This one-arm Phase II study utilized an exact two-stage group sequential design with a 1-week run-in period between the start of SJW treatment and the designated quit date. A total of 37 smokers (ages 18-65 years, smoking > or = 10 cigarettes/day) were started on SJW. Thirteen failed to make a verified quit attempt on the predesignated date and were taken off study resulting in 24 evaluable subjects.

SETTING

Smokers completed clinic visits at a cancer center with interval telephone calls and mailings.

INTERVENTION

Standardized SJW, 450 mg capsules taken orally twice daily along with cessation counseling messages.

MAIN OUTCOME MEASURES

Subjects completed validated surveys and a focused physical examination at baseline. Evaluable subjects were defined as those subjects who made a confirmed quit attempt on their "quit date" 1 week following initiation of SJW. Smoking status was determined through self-report and bioverification using carbon monoxide (CO) testing.

RESULTS

Among evaluable subjects, the 12-week quit rate was 37.5% (9/24). Quitters had no significant change in weight from baseline to 12-weeks cessation. Use of SJW was generally well tolerated.

CONCLUSIONS

Based upon these results (which suggest that SJW may be effective in maintaining smoking cessation) and the high compliance and few AEs, we conclude that SJW demonstrates feasibility for use in smoking cessation. If SJW proves to be effective in larger controlled studies, it could represent a less expensive, more readily accessible and well-tolerated agent to promote tobacco cessation.

Long-term effects of nicotine on the forced swimming test in mice: an experimental model for the study of depression caused by smoke

Large evidence showing an association between depression and tobacco smoking is known. Nicotine is the active chemical responsible for smoking addiction, and its withdrawal may induce in smokers greater sensitivity to stress. Our aim has been to investigate the links between tobacco addiction and depression by studying the long-term effects of repeated administration of nicotine followed by dependence, to forced swimming test, serotonin content and 5-HT(1A) expression in diencephalon. Dependence has been induced by daily subcutaneous injection in mice of nicotine (2mg/kg four injections daily) for 15 days and assessed after nicotine withdrawal with an abstinence scale; control animals received daily subcutaneous injection of saline for the same period. Experiments on forced swimming test have been carried out at t=0 (last day of nicotine or saline treatment), and 15, 30, 45 and 60 days after saline or nicotine withdrawal. Both control mice and nicotine mice have been pre-treated with oral 5-hydroxy-tryptophan (12.5-50mg/kg), precursor of serotonin, before forced swimming test. Nicotine mice have shown on forced swimming test a significant increase of immobility time compared to control mice. This increase was not evident in nicotine mice treated with 5-hydroxy-tryptophan and treatment with the selective serotonin receptorial antagonist WAY 100635 (WAY) abolished 5-hydroxy-tryptophan effects. Evaluation of diencephalic serotonin, performed at t=0 showed an increase of diencephalic serotonin content, while serotonin measured 15, 30, 45 and 60 days after nicotine withdrawal, was significantly reduced in nicotine mice compared to control mice. Western blot analysis showed a great reduction of 5-HT(1A) receptor expression in nicotine mice measured at t=0 (last day of treatment) and at 15 and 30 days after nicotine withdrawal compared to control mice. Our results show that (i) behavioural alterations estimated with forced swimming test and (ii) changes in diencephalic serotonin content and 5-HT(1A) receptor expression, are present since nicotine is withdrawn even after a long time, suggesting a role of serotonin in mood disorders eventually occurring following smoking cessation.

Effect of Hypericum perforatum CO2 extract on the motivational properties of ethanol in alcohol-preferring rats

AIMS

Extracts of Hypericum perforatum (HPE) attenuate voluntary ethanol intake in different lines of alcohol-preferring rats. The present study evaluated the effect of the intragastric (IG) administration of a CO(2) Hypericum perforatum extract (HPCO(2)) on operant ethanol self-administration, as well as on voluntary ethanol intake, after a period of ethanol deprivation in genetically selected Marchigian Sardinian alcohol-preferring rats.

METHODS

HPCO2 was administered by means of an indwelling IG catheter, 1 h before the tests. For the self-administration experiments, the rats were trained to self-administer 10% (v/v) ethanol in 30-min daily sessions under a fixed ratio 1 schedule of reinforcement. HPCO2 was also tested on 0.2% w/v saccharin self-administration. For the ethanol deprivation experiments, rats that had a previous experience with voluntary ethanol drinking were deprived of ethanol for 9 days, whereas water and food were freely available; HPCO2 was given by IG injection 1 h before the ethanol re-presentation.

RESULTS

HPCO2 in doses of 31 or 125 mg/kg but not 7 mg/kg, significantly reduced ethanol self-administration, while it did not modify saccharin self-administration. The same doses of the extract abolished the increased ethanol intake following ethanol deprivation.

CONCLUSIONS

These findings provide evidence that HPCO2 markedly reduces the reinforcing properties of ethanol in the self-administration paradigm, as well as the increase of ethanol intake following ethanol deprivation. These findings further support the view that the use of HPE may represent an interesting pharmacological approach in the treatment of alcohol abuse and alcoholism.

Natural and complementary therapies for substance use disorders

PURPOSE OF REVIEW

To review recent studies that have examined the efficacy of natural and complementary therapies as treatments for substance use disorders and their complications.

RECENT FINDINGS

Despite increasing interest in natural and complementary therapies for substance use disorders, rigorous clinical studies in this area are few in number. Recent clinical studies, although preliminary, have reported potential therapeutic effects for hypericum in the treatment of smoking cessation, for prickly pear extract in the prevention of alcohol hangover and magnesium supplementation as an adjunct to methadone treatment. Other clinical studies have reported negative findings for ginkgo as an adjunctive treatment for cocaine dependence, for artichoke in prevention of alcohol hangover, and acupuncture for alcohol withdrawal. Relevant findings from animal studies are also discussed. Neither vitamin E nor Liv 52 had a useful effect in alcohol-related liver disease. A study of silymarin in baboons, which was undertaken in an attempt to untangle the conflicting findings of human studies, reported a potential for this compound to prevent liver injury. There is increasing awareness of safety issues associated with complementary therapies. Safety issues pertinent to substance use treatment are discussed in this review.

SUMMARY

Several pharmacological and psychosocial treatments for substance use disorders are solidly evidence-based and improve both individual and public health outcomes. At this stage, there remains insufficient evidence to support the use of natural and complementary therapies as a primary intervention for substance use disorders. Further clinical trials are required to clarify the potential role of particular agents.

Long-Term Effects of High Doses of Nicotine on Feeding Behavior and Brain Nitric Oxide Synthase Activity in Female Mice

We studied the long-term effects of repeated doses of nicotine, causing dependence, 120 days after its withdrawal on feeding behavior and on brain nitric oxide (NO) formation in female mice. Nicotine dependence was induced by subcutaneous (s.c.) nicotine injection (2 mg/kg, four injections daily) for 14 days. Daily food intake was evaluated for the entire observational period (120 days). Moreover, 30, 60, and 120 days after nicotine withdrawal, we evaluated food intake, nitrite/nitrate levels, and nitric oxide synthase (NOS) activity and expression in the hypothalamus after food deprivation (24 h). In animals in which nicotine dependence was induced (NM), daily food intake was similar to that of controls (M). However, following food deprivation, NM mice showed i) a significant increase in food intake, ii) changes in weight gain and in hypothalamic nitrite/nitrate levels, and iii) enhancement of hypothalamic neuronal NOS (nNOS) activity. Results indicate that high doses of nicotine producing dependence induce long-term changes in feeding behavior consequent to food deprivation associated to alterations in the brain nitrergic system.