Biochemical Validation of a Self-Administered Carotenoid Intake Screener to Assess Carotenoid Intake in Nonobese Adults

Background

Epidemiological studies have demonstrated an association between carotenoid intake and health. However, an accurate measurement of carotenoid intake is challenging. FFQ is the most commonly used dietary assessment method and is typically composed of 100-200 items. However, the greater participant burden that accompanies a more detailed FFQ provides only a marginal gain in accuracy. Therefore, a brief validated carotenoid intake screener is needed.

Objectives

To conduct secondary analysis evaluating the validity of a newly developed 44-item carotenoid intake screener from The Juice Study: Sensitivity of Skin Carotenoid Status to Detect Change in Intake (NCT03202043) against corresponding plasma carotenoid concentrations (primary) and skin carotenoids (secondary) in nonobese Midwestern American adults.

Methods

Healthy adults (n = 83; 25 men and 58 women) aged 18-65 y (mean age, 32 ± 12 y) with a BMI (in kg/m2) of 18.5-29.9 (mean BMI, 25 ± 3) were recruited between 25 April 2018 and 28 March 2019. Participants completed the carotenoid intake screener weekly during the 8-wk parent study. Plasma carotenoid concentrations were assessed at weeks 0, 4, and 8 using HPLC. Skin carotenoids were assessed weekly using pressure-mediated reflection spectroscopy (RS). Correlation matrices from mixed models were used to determine the correlation between carotenoid intake and plasma and skin carotenoids over time.

Results

The total carotenoid intake, as determined by the carotenoid intake screener, correlated with both the plasma total carotenoid concentration (r = 0.52; P < 0.0001) and the RS-assessed skin carotenoid concentration (r = 0.43; P < 0.0001). Correlations between reported intake and plasma concentrations of α-carotene (r = 0.40; P = 0.0002), cryptoxanthin (r = 0.28; P = 0.0113), and lycopene (r = 0.33; P = 0.0022) were also observed.

Conclusions

The results of this study demonstrate an acceptable relative validity of the carotenoid intake screener to assess total carotenoid intake in adults classified as those having a healthy body or those with overweight.

In silico analysis and experimental validation to exhibit anti-nasopharyngeal carcinoma effects of plumbagin, an anti-cancer compound

BACKGROUND

Nasopharyngeal carcinoma (NPC) is publicly known as a malignant tumor. Our previous study reported that plumbagin exhibits potent anti-cancer actions. Nevertheless, more mechanical details of plumbagin against NPC remain unknown. The present study aimed to unmask the core targets/genes and anti-NPC mechanisms involved in the signaling pathways of plumbagin prior to biochemical validation.

METHODS

A network pharmacology approach was employed to respective identification of mutual and core targets/genes in plumbagin and/treating NPC. Molecular docking determination was used to identify core target proteins for biochemical validation using human and cell line samples.

RESULTS

In total, 60 anti-NPC genes of plumbagin were screened out, and then nine core target genes of plumbagin against NPC were identified accordingly. The enrichment findings revealed detailed biological functions and pharmacological pathways of plumbagin against NPC. Moreover, in silico analysis using molecular docking had determined the core targets for further experimental validation, comprising protein kinase B (AKT1) and sarcoma gene (SRC). In human sample validation, clinical NPC sections showed increased positive expression of AKT1 and SRC. Additionally, plumbagin-treated NPC cells resulted in inactivated protein expression of AKT1 and SRC.

CONCLUSION

The re-identified core targets/genes in the molecular docking report may function as plumbagin-related pharmacological targets for treating NPC via experimental validation. Furthermore, additional anti-NPC molecular mechanisms of plumbagin action were disclosed on the basis of enrichment findings. © 2022 Society of Chemical Industry.

Comparing cotinine and NNAL verification of self-reported smoking status among lung cancer screening eligible population from the 2007-2014 National Health and Nutrition Examination Survey (NHANES)

Background: Biochemical verification of self-reported smoking status is not common among the population eligible for lung cancer screening (LCS). Methods: We used urinary NNAL (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol and its glucuronides) and serum cotinine as the gold standard to determine the validity and reliability of self-reported smoking status from the 2007-2014 National Health and Nutrition Examination Survey (NHANES). Results: We found 2.3% (n = 652, equivalent to 5.3 million weighted population) of adults eligible for LCS according to the current United States Preventive Services Task Force guideline. Self-reported current smoking status performed similarly against NNAL and cotinine: sensitivity [89.7% (95%CI: 84.9%-94.5%) vs. 89.5% (95%CI: 84.8%-94.3%)]; specificity [99.7% (95%CI: 99.2%-100.0%) vs. 100% (95%CI:100%-100%)]; positive predictive value (PPV) and negative predictive value (NPV) were 99.8% (95%CI:99.4%-100.0%) versus 100% (95%CI:100%-100%) and 85.3% (95%CI: 79.1%-91.5%) versus 85.1% (95%CI: 79.1%-1.0%), respectively; and Kappa [86.5% (95%CI:80.5%-92.5%) vs. 86.5% (95%CI:80.6%-92.3%)]. Performance measures were better among females than males; worst among the non-Hispanic white and best among other race/ethnicity group. The validity and reliability of self-reported smoking status increased with increasing cutpoint levels of both NNAL and cotinine. Conclusions: Self-reported smoking status among people who are at high risk of lung cancer is reasonably reliable. The difference between using NNAL and cotinine appears to be minimal.

Biochemical Validation of Self-Reported Smokeless Tobacco Abstinence among Smokeless Tobacco Users: Results from a Clinical Trial of Varenicline in India

The validity of self-reported tobacco use is often questioned given the potential for underestimation of use. This study used data from a double-blind, placebo-controlled clinical trial of varenicline for smokeless tobacco dependence in India to evaluate the accuracy of self-reported smokeless tobacco cessation using biochemical validation procedures and to evaluate correlates of reporting inaccuracy. Smokeless tobacco users attending a dental clinic at AIIMS were randomized to placebo or varenicline; all participants received counseling. Detailed smokeless tobacco use was recorded and abstinence was defined as cotinine-verified 7-day point prevalence cessation (cotinine < 50 ng/ml) and breath CO > 10 ppm at the end of 12 weeks of treatment. One-half of study completers (82/165) self-reported abstinence. Biochemical verification confirmed that (65.9%) subjects provided accurate self-reports while (34.1%) participants underreported tobacco use. These data indicate poor agreement between self-reported and biochemically confirmed abstinence (κ = -0.191). Underreporters of tobacco use had significantly higher baseline cotinine (p < 0.05), total craving (p < 0.012), and negative reinforcement craving (p < 0.001) vs. those whose self-reports were correctly verified. These findings provide evidence to support the need for biochemical validation of self-reported abstinence outcomes among smokeless tobacco users in cessation programs in India and identify high levels of pretreatment cotinine and craving levels as potential correlates of false reporting.

Validation of smoking cessation self-reported by patients with chronic obstructive pulmonary disease

PURPOSE

The present study reports on the biochemical validation of the self-reported smoking status of patients with chronic obstructive pulmonary disease (COPD). The objective is to establish the proportion of overestimation of self-reported success rates.

METHODS

A cross-sectional smoking-status validation study including 60 patients with COPD who reported that they had stopped smoking. In the analysis of urine samples, a cut-off point of 50 ng/mL of cotinine was used.

RESULTS

At the time of biochemical validation, 55 patients reported that they had quit smoking while five patients resumed smoking. Smoking status was biochemically confirmed for 43 patients (78%) and 12 patients (22%) were classified as smokers. The sensitivity of the self- report of smoking was 29% and the specificity was 100%.

CONCLUSION

Many primary care patients with COPD do not provide valid information on their smoking status, which hamper adequate therapeutic interventions. Integration of biochemical validation in daily care could overcome this problem, but may harm the doctor-patient relationship.