Physiological Significance of Discrimination on Stress Markers, Obesity, and LDL Oxidation among a European American and African American Cohort of Females

Pilot study assessing gut microbial diversity among sexual and gender minority young adults

Evidence supports that people identifying as a sexual or gender minority (SGMs) experience minority-related stress resulting from discrimination or expectations of prejudice, and that this is associated with increased mental and physical health problems compared to cisgender heterosexuals. However, the biological mechanisms driving minority-related stress impacts remain unknown, including the role of the gut microbiome. Thus, the aim of this study was to determine the relationship between SGM status and gut microbiome health among young adults attending a 4-year university. To this end, a prospective pilot study was completed in the fall and spring semesters of 2021-22. Self-identified SGMs (N = 22) and cisgender-heterosexuals (CIS-HET, N = 43) completed in-person interviews to provide mental health data and demographic information. Nail and saliva samples were collected at the time of interview to quantify chronic and acute cortisol. Stool samples were collected within 48 hours of interview for microbiome analysis. Assessment of the gut microbiota identified a significant reduction in alpha diversity among the SGM group, even when adjusting for mental health outcome. SGM group showed trends for higher abundance of microbes in phylum Bacteroidetes and lower abundance of microbes in phyla Firmicutes, Actinobacteria, and Proteobacteria compared to the CIS-HET group. These findings support that the gut microbiome could be contributing to negative health effects among the SGM community.

Racial/ethnic disparities in chronic wounds: Perspectives on linking upstream factors to health outcomes

This review explores the complex relationship between social determinants of health and the biology of chronic wounds associated with diabetes mellitus, with an emphasis on racial/ethnic disparities. Chronic wounds pose significant healthcare challenges, often leading to severe complications for millions of people in the United States, and disproportionally affect African American, Hispanic, and Native American individuals. Social determinants of health, including economic stability, access to healthcare, education, and environmental conditions, likely influence stress, weathering, and nutrition, collectively shaping vulnerability to chronic diseases, such as obesity and DM, and an elevated risk of chronic wounds and subsequent lower extremity amputations. Here, we review these issues and discuss the urgent need for further research focusing on understanding the mechanisms underlying racial/ethnic disparities in chronic wounds, particularly social deprivation, weathering, and nutrition, to inform interventions to address these disparities.

A cross-sectional study observing the association of psychosocial stress and dietary intake with gut microbiota genera and alpha diversity among a young adult cohort of black and white women in Birmingham, Alabama

BACKGROUND

The relationships between psychosocial stress and diet with gut microbiota composition and diversity deserve ongoing investigation. The primary aim of this study was to examine the associations of psychosocial stress measures and dietary variables with gut microbiota genera abundance and alpha diversity among young adult, black and white females. The secondary aim was to explore mediators of psychosocial stress and gut microbiota diversity and abundance.

METHODS

Data on 60 females who self-identified as African American (AA; n = 29) or European American (EA; n = 31) aged 21-45 years were included. Cortisol was measured in hair and saliva, and 16S analysis of stool samples were conducted. Discrimination experiences (recent and lifetime), perceived stress, and depression were evaluated based on validated instruments. Spearman correlations were performed to evaluate the influence of psychosocial stressors, cortisol measures, and dietary variables on gut microbiota genus abundance and alpha diversity measured by amplicon sequence variant (ASV) count. Mediation analyses assessed the role of select dietary variables and cortisol measures on the associations between psychosocial stress, Alistipes and Blautia abundance, and ASV count.

RESULTS

AA females were found to have significantly lower ASV count and Blautia abundance. Results for the spearman correlations assessing the influence of psychosocial stress and dietary variables on gut microbiota abundance and ASV count were varied. Finally, diet nor cortisol was found to partially or fully mediate the associations between subjective stress measures, ASV count, and Alistipes and Blautia abundance.

CONCLUSION

In this cross-sectional study, AA females had lower alpha diversity and Blautia abundance compared to EA females. Some psychosocial stressors and dietary variables were found to be correlated with ASV count and few gut microbiota genera. Larger scale studies are needed to explore the relationships among psychosocial stress, diet and the gut microbiome.

A cross-sectional study observing the association of psychosocial stress and dietary intake with gut microbiota genera and alpha diversity among a young adult cohort of black and white women in Birmingham, Alabama

Background

The relationships between psychosocial stress and diet with gut microbiota composition and diversity deserve ongoing investigation. The primary aim of this study was to examine the associations of psychosocial stress measures and dietary variables with gut microbiota genera abundance and alpha diversity among young adult, black and white females. The secondary aim was to explore mediators of psychosocial stress and gut microbiota diversity and abundance.

Methods

Data on 60 females who self-identified as African American (AA; n = 29) or European American (EA; n = 31) aged 21-45 years were included. Cortisol was measured in hair and saliva, and 16S analysis of stool samples were conducted. Discrimination experiences (recent and lifetime), perceived stress, and depression were evaluated based on validated instruments. Spearman correlations were performed to evaluate the influence of psychosocial stressors, cortisol measures, and dietary variables on gut microbiota genus abundance and alpha diversity measured by amplicon sequence variant(ASV) count. Mediation analyses assessed the mediating role of select dietary variables and cortisol measures on the associations between psychosocial stress, Alistipes and Blautia abundance, and ASV count.

Results

AA females were found to have significantly lower ASV count and Blautia abundance. Results for the spearman correlations assessing the influence of psychosocial stress and dietary variables on gut microbiota abundance and ASV count were varied. Finally, diet nor cortisol was found to partially or fully mediate the associations between subjective stress measures, ASV count, and Alistipes and Blautia abundance.

Conclusion

In this cross-sectional study, AA females had lower alpha diversity and Blautia abundance compared to EA females. Some psychosocial stressors and dietary variables were found to be correlated with ASV count and few gut microbiota genera. Larger scale studies are needed to explore the relationships among psychosocial stress, diet and the gut microbiome.

Relational and individual stress pathways linking discrimination and ageing cardiometabolic health

Perceived discrimination is a significant risk factor for worse ageing health outcomes. Yet, the specific individual and relational stress pathways linking discrimination to disease are less understood, especially in the context of cardiometabolic health. We tested family stress and psychophysiological distress (negative affect and high-risk lipid/fat metabolism) as mediators linking perceived discrimination to cardiometabolic morbidity and health appraisal over 20 years for midlife adults. Using data from participants who completed the Biomarker Project (2004-2009) of the Midlife in the U.S. project, and examining data over the study's three waves (1995-1996, 2004-2006, and 2013-2014), we used structural equation modelling to test pathways for participants who reported zero cardiometabolic conditions at baseline (n = 799). Greater Time 1 discrimination was associated with greater Time 2 family strain, which was in turn associated with worse negative affect; worse Time 2 negative affect was associated with worse Time 3 health appraisal; metabolic lipids risk did not serve as an indirect pathway to Time 3 cardiometabolic morbidity (χ²  = 147.74, p < 0.001; RMSEA = 0.056; CFI = 0.902; SRMR = 0.047). The inclusion of family in interventions to mitigate the impact of discrimination may be indicated for promoting cardiometabolic wellness.

Composition, anti-LDL oxidation, and non-enzymatic glycosylation inhibitory activities of the flavonoids from Mesembryanthemum crystallinum

This study identified the constituents of purified flavonoid (PEF) isolated from Mesembryanthemum crystallinum and examined their inhibitory effects on low-density lipoprotein (LDL) oxidation and non-enzymatic glycosylation. More than 30 kinds of flavonoid compounds were identified in M. crystallinum, including tangeretin, nobiletin, farrerol, protocatechuic aldehyde, diosmin, and rutin. Moreover, tangeretin corresponds to approximately 51% of the total identified flavonoids. PEF had a low IC50 value for 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH·), hydroxyl radical (·OH), and superoxide anion free radical (O2-·) scavenging. They were found to effectively delay and inhibit the production of conjugated diene (CD) and thiobarbituric acid reactive substance (TBARS) during LDL oxidation. Meanwhile, scanning electron microscopy (SEM) of the LDL oxidation incubation system with PEF showed a smooth and dense surface, with no obvious cavitation phenomenon. Furthermore, PEF effectively inhibited the production of LDL glycosylation products and showed a strong inhibitory effect in the latter stage. The electrophoresis of advanced glycosylation end products (AGEs) further confirmed that PEF can effectively prevent the cross-linking between glucose and proteins, protecting LDL from glycosylation-induced damage.

Comparison of Perceived Weight Discrimination between Polish and German Patients Underwent Bariatric Surgery or Endoscopic Method versus Conservative Treatment for Morbid Obesity: An International Multicenter Study

Objectives: The aim of this study was to compare the level of discrimination among patients with obesity living in Poland and Germany. Methods: This was a retrospective cross-sectional international multicenter survey study including 564 adult participants treated for morbid obesity at selected healthcare facilities in Germany (210 patients) and in Poland (354 patients). Discrimination was evaluated using a custom-made questionnaire based on the related literature. Results: The level of obesity discrimination did not differ between German and Polish patients (p = 0.4282). The presence of obesity was reported to be associated to a large or a very large extent with the feeling of social exclusion and discrimination by 46.63% of German participants and 42.09% of Polish ones (p = 0.2934). The mean level of discrimination related to the lack of employment was higher in patients who underwent bariatric surgery or endoscopic method than in those who underwent conservative treatment (for Germany: 2.85 ± 1.31 (median, 3) vs. 2.08 ± 1.31 (median, 1), p = 0.002; for Poland: 2.43 ± 1.15 (median, 2) vs. 1.93 ± 1.15 (median, 1), p = 0.005). The level of discrimination was associated with sex, age, the degree of obesity, and treatment-related weight loss (p < 0.05). Conclusions: Our findings confirm that obesity significantly affects the social and economic well-being of patients. There is a great need to reduce weight stigma and to take measures to alleviate the socioeconomic and psychological burden of obesity.

Cross-sectional relation of long-term glucocorticoids in hair with anthropometric measurements and their possible determinants: A systematic review and meta-analysis

BACKGROUND

Long-term glucocorticoids (HairGC) measured in scalp hair have been associated with body mass index (BMI), waist circumference (WC), and waist-hip-ratio (WHR) in several cross-sectional studies. We aimed to investigate the magnitude, strength, and clinical relevance of these relations across all ages.

METHODS

We performed a systematic review and meta-analysis (PROSPERO registration CRD42020205187) searching for articles relating HairGC to measures of obesity. Main outcomes were bivariate correlation coefficients and unadjusted simple linear regression coefficients relating hair cortisol (HairF) and hair cortisone (HairE) to BMI, WC, and WHR.

RESULTS

We included k = 146 cohorts (n = 34,342 individuals). HairGC were positively related to all anthropometric measurements. The strongest correlation and largest effect size were seen for HairE-WC: pooled correlation 0.18 (95%CI 0.11-0.24; k = 7; n = 3,158; I²  = 45.7%) and pooled regression coefficient 11.0 cm increase in WC per point increase in 10-log-transformed HairE (pg/mg) on liquid-chromatography-(tandem) mass spectrometry (LC-MS) (95%CI 10.1-11.9 cm; k = 6; n = 3,102). Pooled correlation for HairF-BMI was 0.10 (95%CI 0.08-0.13; k = 122; n = 26,527; I²  = 51.2%) and pooled regression coefficient 0.049 kg/m² per point increase in 10-log-transformed HairF (pg/mg) on LC-MS (95%CI 0.045-0.054 kg/m² ; k = 26; n = 11,635).

DISCUSSION

There is a consistent positive association between HairGC and BMI, WC, and WHR, most prominently and clinically relevant for HairE-WC. These findings overall suggest an altered setpoint of the hypothalamic-pituitary-adrenal axis with increasing central adiposity.

The Cardiovascular Conundrum in Ethnic and Sexual Minorities: A Potential Biomarker of Constant Coping With Discrimination

Background: A paradoxical profile of greater elevated sympathetic vasoconstriction (increased total peripheral resistance, TPR) and increased vagally-mediated heart rate variability (HRV) -the so-called Cardiovascular Conundrum- has been reported in African Americans (AAs) both at rest and in response to orthostasis. Whereas some authors have attributed this pattern to genetic factors, others have pointed to the potential role of coping with repeated racial discrimination.

Objective: To disentangle between these alternative explanations, we have examined the hemodynamic profile of another population that is likely to be exposed to episodes of discrimination, i.e., sexual minorities.

Methods: The first study was conducted on a sample of AAs and European Americans (EAs) with the aim of replicating previous results on the Cardiovascular Conundrum. In the second study, lesbian, gay, and bisexual (LGB) people, matched by age and sex with heterosexual participants, underwent a hemodynamic and autonomic assessment at rest and during an emotional (in the experimental group, both LGB-related and non LGB related), and a cognitive stressor.

Results: The first study confirmed a pattern of higher resting HRV, paired with higher TPR, in AAs compared to EAs. In the second study, compared to heterosexuals, the LGB group showed the Cardiovascular Conundrum pattern, characterized by greater HRV and higher TPR at baseline and a more vascular hemodynamic profile and prominent compensation deficit in response to both tasks, and particularly during the LGB-related emotional task. However, in LGB only, the vascular response was negatively correlated with perceived discrimination.

Conclusion: Present preliminary results are discussed in terms of maladaptive physiological consequences of exposure to chronic stress and the chronic use of dysfunctional emotion regulation strategies such as suppression.

Deciphering the Association Between Hypothalamus-Pituitary-Adrenal Axis Activity and Obesity: A Meta-Analysis

OBJECTIVE

Both the cortisol awakening response (CAR; corresponding to the state measurement) and hair cortisol concentration (HCC; corresponding to the trait measurement) are considered reliable markers of hypothalamus-pituitary-adrenal axis activity. Because cortisol has long been associated with adiposity, this systematic review and meta-analysis aims to summarize and compare the literature around CAR and HCC and their association with obesity or fat distribution indices.

METHODS

The PubMed, Web of Science (Web of Science Core Collection and Medline), EBSCO Information Services, Embase, and PsycNET databases were searched, and full-text articles investigating the association between CAR or HCC and markers of adiposity in humans were included. Meta-analyses were then performed to compare studies associating CAR or HCC with BMI (a marker of general adiposity) and waist circumference (a marker of fat distribution).

RESULTS

The results of this review highlight inconsistencies in cortisol sampling and CAR computation, which makes comparisons between studies difficult. It was found that adiposity indices are not associated with CAR but that they correlate significantly and positively with HCC. The subgroup analysis hinted to possible age differences in the magnitude of the association between HCC and BMI.

CONCLUSIONS

Trait rather than state measurement of the hypothalamus-pituitary-adrenal axis activity is associated with increased general and abdominal adiposity in humans.