Impacts of genetic variation in <i>UGT2B17</i> and <i>UGT2B10</i>.

<p>Data presented as Mean (95% Confident Interval).</p>1<p>The urinary total nicotine equivalents and urinary 3HC-Glu/total 3HC ratios were only available for 426 individuals.</p>2<p>No statistically significant difference was observed in any of the demographic variables when the <i>UGT2B10*2/*2</i> group was pooled with the <i>*1/*2</i> group. Statistical comparison performed by Mann-Whitney or Kruskal-Wallis tests.</p

The urinary 3HC-Gluc over 3HC-free ratio did not correlate NMR or nicotine consumption.

<p>The urinary 3HC-Gluc over 3HC-free ratio did not correlate with either plasma NMR (<b>A</b>) or urinary NMR (<b>B</b>). The urinary 3HC-Gluc over 3HC-free ratio also did not correlate with either plasma cotinine (<b>C</b>) or the urinary TNE (<b>D</b>).</p

The association between <i>UGT2B17</i> gene deletion and <i>UGT2B10*2</i> with NMR.

<p><i>UGT2B17</i> gene deletion was not associated with plasma (<b>A</b>) or urinary NMR (<b>B</b>). <i>UGT2B10*2</i> genotype was not associated with plasma (<b>C</b>) or urinary NMR (<b>D</b>). Urinary samples were only available for 426 individuals. IQR = Interquartile range. No significant difference in plasma NMR between <i>UGT2B10</i> genotype groups was found when the <i>UGT2B10*1/*2</i> and <i>*2/*2</i> groups were pooled. Similar findings were observed after statistically adjusting for gender, age and body mass index.</p

Time course of nicotine plasma concentrations in mice pretreated with menthol.

<p>Nicotine was administered (2.5 mg/kg s.c.), 30 min after pretreatment with vehicle or menthol (100 mg/kg i.p.). Each time point represents the mean ± SEM of 7 to 10 animals. For the vehicle pretreatment, values for nicotine plasma levels at 2 h were below the limits of detection. Each point represents the mean ± SE of 8–12 mice. Nic = nicotine.</p

Effects of menthol pretreatment on nicotine-induced antinociception and hypothermia dose-response curves in mice.

<p>Vehicle or menthol (100 mg/kg, ip) was administered 30 min before various doses of nicotine (0.5, 1.5, 2, and 2.5 mg/kg s.c.) and mice were tested in <b>(A)</b> the tail-flick test, <b>(B)</b> the hot-plate test, and <b>(C)</b> hypothermia. Each point represents the mean ± SE of 8–12 mice.</p

Nicotine plasma levels in adult male ICR mouse after pre-treatment with vehicle or menthol in the withdrawal testing.

<p>*P<0.05 compared to vehicle/nicotine group.</p><p>Mice received nicotine (12 mg/kg/day) for 7 days. On day 8, mice were sacrificed and blood samples were drawn. Values are shown as mean ± S.E.M. (n = 6-8/group)</p

Cell proliferation.

<p>DG proliferation assessed from Ki67-immunostained brain sections from juvenile (P15) and adolescent (P41) male offspring exposed to saline (controls) or nicotine throughout prenatal and postnatal development. Representative micrographs of Ki67-IR cells (arrows) in the subgranular zone or adjacent granule cell layer (gcl) in control P15 (<b>A</b>) and P41 (<b>B</b>) offspring. No significant difference in numbers of Ki67-IR cells was found in the dorsal hippocampus of P15 (<b>C</b>; p = 0.70) or P41 (<b>D</b>; p = 0.17) offspring. Scale bar = 25 µm.</p

Lack of Associations of <i>CHRNA5-A3-B4</i> Genetic Variants with Smoking Cessation Treatment Outcomes in Caucasian Smokers despite Associations with Baseline Smoking

<div><p><i>CHRNA5-A3-B4</i> variants, rs16969968, rs588765 and rs578776, are consistently associated with tobacco consumption among smokers, but the association with smoking cessation is less consistent. Among the studies that reported significant associations with cessation, the effects were observed in smokers treated with placebo treatment in some studies and conversely in those receiving active pharmacological therapy (bupropion and nicotine replacement therapies) in others. Thus, it remains unclear whether <i>CHRNA5-A3-B4</i> is a useful marker for optimizing smoking cessation. Using data from 654 Caucasian smokers treated with placebo, nicotine patch or varenicline, we investigated whether <i>CHRNA5-A3-B4</i> variants were associated with smoking cessation outcomes, and whether there were significant genotype-by-treatment or haplotype-by-treatment interactions. We observed no significant associations between <i>CHRNA5-A3-B4</i> variants and smoking cessation, despite replicating previous associations with baseline tobacco consumption. At end of treatment the effect size on smoking cessation in the placebo, patch and varenicline groups for rs16969968 [GG vs. GA+AA] was OR = 0.66 (P = 0.23), OR = 1.01 (P = 0.99), and OR = 1.30 (P = 0.36) respectively, of rs588765 [CC vs. CT+TT] was OR = 0.96 (P = 0.90), OR = 0.84 (P = 0.58), and OR = 0.74 (P = 0.29) respectively, and for rs578776 [GG vs. GA+AA] on smoking cessation was OR = 1.02 (P = 0.95), OR = 0.75 (P = 0.35), and OR = 1.20 (P = 0.51) respectively. Furthermore, we observed no associations with cessation using the <i>CHRNA5-A3-B4</i> haplotype (constructed using rs16969968 and rs588765), nor did we observe any significant genotype-by-treatment interactions, with or without adjusting for the rate of nicotine metabolism (all P>0.05). We also observed no significant genetic associations with 6 month or 12 month smoking abstinence. In conclusion, we found no association between <i>CHRNA5-A3-B4</i> variants and smoking cessation rates in this clinical trial; however, as expected, significant associations with baseline tobacco consumption were replicated. Our data suggest that <i>CHRNA5-A3-B4</i> gene variants do not exhibit a robust association with smoking cessation and are unlikely to be useful for clinically optimizing smoking cessation pharmacotherapy for Caucasian smokers.</p></div

Effects of menthol on the time course of nicotine’s effects in (A) the tail-flick test, (B) the hot-plate assay, and (C) body temperature in mice.

<p>Animals were pretreated with either menthol (100 mg/kg i.p.) or vehicle and 30 min later received nicotine (2.5 mg/kg, s.c.). A control group (vehicle/vehicle) is also represented in all three tests. Mice were tested at different time points after injection. Each point represents the mean ± SE of 8–12 mice. *p < 0.05 compared with vehicle/nicotine group.</p

Summary of the potency of nicotine in male and female mice in different behavioral tests.

<p>ED₅₀ values (±CL) were calculated from the dose-response curve of the different groups and expressed as mg/kg.</p><p>Animals were pretreated with either vehicle or menthol (100 mg/kg, i.p.) followed by nicotine (2.5 mg/kg s.c.) at different doses and then tested 5 min (tail-flick and hot-plate tests) or 20 min later (hypothermia). Each point represents the mean ± SE of 6 to 8 mice.</p