C-reactive protein and depressed mood in a sub-group of smokers during nicotine abstinence

Two-Hour Nicotine Withdrawal Improves Inhibitory Control Dysfunction in Male Smokers: Evidence from a Smoking-Cued Go/No-Go Task ERP Study

Purpose

Nicotine withdrawal is a multifaceted physiological and psychological process that can induce a spectrum of mood disturbances. Gaining a more nuanced understanding of how pure nicotine withdrawal influences cognitive control functions may provide valuable insights for the enhancement of smoking cessation programs. This study investigated changes in inhibitory control function in smokers after 2-hour nicotine withdrawal using the event-related potential (ERP) technique.

Participants and Methods

28 nicotine dependence (ND) patients and 28 health controls (HCs) completed a smoking-cued Go/No-go task containing two different types of picture stimuli, smoking-cued and neutral picture stimuli. We analyzed the behavioral and ERP data using a mixed model Repeated Measure Analysis of Variance (ANOVA).

Results

No-go trials accuracy rate (ACC) at baseline (time 1) was lower in the ND group compared to HCs with smoking-cued stimuli, and No-go trials ACC after 2-hour nicotine withdrawal (time 2) was not lower in the ND group compared to HCs. When confronted with smoking-cued stimuli, the No-go trials ACC was higher in time 2 than in time 1 in the ND group. For the ERP component, the No-go N2 amplitudes in the ND group with smoking-cued stimuli were lower than that of HCs, whereas after 2-hour nicotine withdrawal, the ND group's No-go N2 amplitudes higher than that at time 1, and did not differ from that of HCs. No-go P3 amplitudes were not significantly different between the two groups.

Conclusion

Evidenced from ERP data, ND patients have an inhibitory control dysfunction in the face of smoking cues, which is mainly manifested in the early stage of response inhibition rather than in the late stage. Two-hour nicotine withdrawal improves inhibitory control dysfunction in ND patients. The No-go N2 component is an important and sensitive neuroelectrophysiological indicator of inhibitory control function in ND patients.

Two-Hour Tobacco Abstinence Has No Effect on Cognitive Control in Male Patients With Nicotine Dependence: An ERP Study

The average nicotine half-life in body tissues is 2 h. Understanding the influence of pure nicotine abstinence on cognitive control may be helpful in eliminating nicotine dependence (ND) and preventing smoking relapse. This study was to investigate the effects of 2-h tobacco abstinence on cognitive control in patients with ND. Twenty-five patients with ND completed event-related potential (ERP) P300 measurements at the normality state and the abstinence state. Twenty-five healthy controls (HCs) were measured with P300 twice with a 2-h time interval. HAMD and HAMA were used to assess the emotional state. Results showed that there were significant differences in Carbon monoxide (CO) levels between the abstinence state and the normality state in the ND group. There were no significant differences in HAMD and HAMA scores for the abstinence state in the ND group or the normality state in the ND group and the HC group. For P3a, P3b amplitude, and P3a latency, the main effect for ND group was significant. For P3a, P3b amplitude, and latency, the interaction effect for group × time point was not significant, and the main effect for time point was not significant. It concluded that patients with ND present cognitive control deficits, and 2-h tobacco abstinence has no effect on cognitive control deficits in male patients with ND. Our findings may be helpful in eliminating nicotine dependence and preventing smoking relapse.

HIV infection and drugs of abuse: role of acute phase proteins

Background

HIV infection and drugs of abuse such as methamphetamine (METH), cocaine, and alcohol use have been identified as risk factors for triggering inflammation. Acute phase proteins such as C-reactive protein (CRP) and serum amyloid A (SAA) are the biomarkers of inflammation. Hence, the interactive effect of drugs of abuse with acute phase proteins in HIV-positive subjects was investigated.

Methods

Plasma samples were utilized from 75 subjects with METH use, cocaine use, alcohol use, and HIV-positive alone and HIV-positive METH, cocaine, and alcohol users, and age-matched control subjects. The plasma CRP and SAA levels were measured by ELISA and western blot respectively and the CD4 counts were also measured.

Results

Observed results indicated that the CRP and SAA levels in HIV-positive subjects who are METH, cocaine and alcohol users were significantly higher when compared with either drugs of abuse or HIV-positive alone. The CD4 counts were also dramatically reduced in HIV-positive with drugs of abuse subjects compared with only HIV-positive subjects.

Conclusions

These results suggest that, in HIV-positive subjects, drugs of abuse increase the levels of CRP and SAA, which may impact on the HIV infection and disease progression.

Smoking and atherosclerotic cardiovascular disease: part II: role of cigarette smoking in cardiovascular disease development

Potential mechanisms and biomarkers of atherosclerosis related to cigarette smoking - a modifiable risk factor for that disease - are discussed in this article. These include smoking-associated inflammatory markers, such as leukocytes, high-sensitivity C-reactive protein, serum amyloid A, ICAM-1 and IL-6. Other reviewed markers are indicative for smoking-related impairment of arterial endothelial function (transcapillary leakage of albumin, inhibition of endogenous nitric oxide synthase activity and reduced endothelium-dependent vasodilation) or point to oxidative stress caused by various chemicals (cholesterol oxidation, autoantibodies to oxidized low-density lipoprotein, plasma levels of malondialdehyde and F(2)-isoprostanes and reduced antioxidant capacity). Smoking enhances platelet aggregability, increases blood viscosity and shifts the pro- and antithrombotic balance towards increased coagulability (e.g., fibrinogen, von Willebrand factor, ICAM-1 and P-selectin). Insulin resistance is higher in smokers compared with nonsmokers, and hemoglobin A1c is dose-dependently elevated, as is homocysteine. Smoke exposure may influence the kinetics of markers with different response to transient or chronic changes in cigarette smoking behavior.

The role of nicotine on respiratory sensory gating measured by respiratory-related evoked potentials

Respiratory perception can be altered by changes in emotional or psychological states. This may be due to affective (i.e., anxiety) modulation of respiratory sensory gating. Nicotine withdrawal induces elevated anxiety and decreased somatosensory gating. Respiratory sensory gating is evidenced by decreased amplitude of the respiratory-related evoked potentials (RREP) N1 peak for the second occlusion (S2) when two 150-ms occlusions are presented with a 500-ms interval during an inspiration. The N1 peak amplitude ratio of the S2 and first occlusion (S1) (S2/S1) is <0.5 and due to central neural sensory gating. We hypothesized that withdrawal from nicotine is anxiogenic and reduces respiratory gating in smokers. The RREP was recorded in smokers with 12-h withdrawal from nicotine and nonsmokers using a paired occlusion protocol. In smokers, the RREP was measured after nicotine withdrawal, then with either nicotine or placebo gum, followed by the second RREP trial. Nonsmokers received only placebo gum. After nicotine withdrawal, the smokers had a higher state anxiety compared with nonsmokers. There was a significant interaction between groups (nonsmokers vs. smokers with nicotine vs. smokers with placebo) and test (pre- vs. posttreatment) in RREP N1 peak amplitude S2/S1. The S2/S1 in the smokers were larger than in nonsmokers before treatment. After gum treatment, the smoker-with-placebo group had a significantly larger S2/S1 than the other two groups. The S2/S1 was significantly decreased after the administration of nicotine gum in smokers due to significantly decreased S2 amplitudes. The RREP Nf and P1 peaks were unaffected. These results demonstrated that respiratory sensory gating was decreased in smokers after nicotine withdrawal. Nicotine increased respiratory sensory gating in smokers with a S2/S1 similar to that of the nonsmokers. Nicotine did not change respiratory sensory information arrival, but secondary information processing in respiratory sensation.

Risk indicators of metabolic syndrome in young adults: A preliminary investigation on the influence of tobacco smoke exposure and gender

BACKGROUND

Metabolic syndrome is characterized by hypertension, dyslipidemia, insulin resistance, and obesity. Limited investigations have studied early indicators of metabolic syndrome in healthy young adults before diagnosis of disease.

PURPOSE

The purpose of this investigation is to identify shifts in cardiovascular (CV), metabolic, and immune variables consistent with metabolic syndrome but occurring before development of the disorder, and to determine whether these variables are influenced by gender or cigarette smoking.

METHODS

A pilot study of 41 subjects ages 18 to 39 years, with 20 smokers and 21 nonsmokers, was undertaken. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured to evaluate CV status; cholesterol, body mass index, leptin, percent glycated albumin, and homocysteine were measured to evaluate metabolic status; C-reactive protein, interleukin-1beta, and interleukin-10 were measured to evaluate immunologic status. Risk scores were assigned to each indicator, and total risk score was computed.

RESULTS

Men had higher SBP (P<.001), DBP (P=.046), and body mass index (P=.01), whereas women had higher leptin (P=.002). Total risk scores in men were greater (P=.02). There was no effect of smoking on risk score, related to the increase in two risks for smokers (SBP, P=.04, DBP; P=.027) reciprocated by a decrease in another (percentage of glycated albumin; P=.02).

CONCLUSION

Risk factors contributing to metabolic syndrome are present and highest in young men compared with women, whereas the effects of cigarette smoking on the syndrome are mixed. Early intervention to reduce modifiable risks may prevent full expression of disease.

Inflammatory, autoimmune, chronic diseases: bad diet and physical inactivity are causes or effects?

It is now well established that most chronic diseases, especially those identified as inflammatory, are statistically correlated with some typical dietary excesses and physical inactivity. But do really these habits cause the diseases, or they result from them? Current opinion favours the first option, but fails to explain why the satisfaction of eating, naturally evolved in our brains to produce health, apparently induces countless millions of people to eat unrestrictedly until becoming mortally sick, whereas trying to keep a theoretically healthy diet is most often a real torture. The inverse explanation makes much more sense: since inflammation produces much heat, calorie-rich diets are required. An inflamed digestive tract lacks digestive power and is easily irritated or damaged by solid objects, therefore requiring a refined, concentrated, low-fibre diet. And inflamed or merely sick organisms are easily exhausted by physical effort, hence physical inactivity. This study confirms that, most probably, the primary causes of inflammatory diseases are always external inflammatory agents, like infectious micro-organisms or toxic substances, of which a particularly ubiquitous example is nicotine. High-calorie/low-fibre diets and physical inactivity are direct consequences of generalised inflammation. Inversely, in most cases, physical exercise and moderation in eating, by themselves, cannot substantially suppress inflammations, but they can prevent them from being further reinforced by the neural reward system. Moreover, diets and exercise causing important suffering will usually do more harm than good, especially to children and young people, not to mention pregnant or nursing women. Only the identification and elimination of the inflammatory agents can efficiently prevent and cure inflammatory diseases, and currently nicotine, absorbed intentionally or passively, from tobacco or other sources, must be considered the chief suspect because of its inflammatory power, ubiquity and addictive properties.

Exposure to nicotine is probably a major cause of inflammatory diseases among non-smokers

This article assesses the hypothesis that most inflammatory diseases are conditioned responses caused by the psychoactive action of nicotine. Even in very 'light' passive smokers, the repeated nicotinic stimulation of the reward system can produce, through classical and subsequent operant conditioning, unconscious addiction to most relevant perceptions occurring simultaneously, including the artificial, non-localised sensation of pain or sickness caused by the action of nicotine on the nociceptive 'cholinergic anti-inflammatory pathway'. During nicotine abstinence and especially under stress, the brain previously addicted to this pain is compelled to reproduce it by the only method available without nicotine: causing lesions or cellular stress in one's organism, for example, by triggering intense inflammations. The author's observations and two independent studies have confirmed that nicotine withdrawal causes inflammatory crises. Furthermore, there is evidence that severe inflammations can be triggered even by almost unnoticeable exposures to nicotine, for example, by staying several minutes outdoors at a few metres from smokers. This has been clearly observed by one patient and can be deduced from theoretical considerations (sensitivity of neural pathways and cumulativeness of conditioning processes) and an animal experimental reference, and is confirmed by the fact that most inflammatory diseases affect similarly all non-smokers regardless of their apparent exposure to nicotine, despite the proven relation between nicotine withdrawal and inflammation. This sensitivity implies that the outdoors atmosphere of most densely populated urban areas represents now a serious health hazard, probably requiring the prohibition of all smokable forms of nicotine. The usual anti-smoking measures focused on closed spaces are inefficient against this danger.