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1.
Stress ; 26(1): 2210687, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37154816

RESUMO

The brain is the key organ that orchestrates the stress response which translates to the retina. The retina is an extension of the brain and retinal symptoms in subjects with neurodegenerative diseases substantiated the eye as a window to the brain. The retina is used in this study to determine whether chronic stress reflects neurodegenerative signs indicative of neurodegenerative conditions. A three-year prospective cohort (n = 333; aged 46 ± 9 years) was stratified into stress-phenotype cases (n = 212) and controls (n = 121) by applying the Malan stress-phenotype index. Neurodegenerative risk markers included ischemia (astrocytic S100 calcium-binding protein B/S100B); 24-h blood pressure, proteomics; inflammation (tumor-necrosis-factor-α/TNF-α); neuronal damage (neuron-specific-enolase); anti-apoptosis of retinal-ganglion-cells (beta-nerve-growth-factor), astrocytic activity (glial-fibrillary-acidic-protein); hematocrit (viscosity) and retinal follow-up data [vessels; stress-optic-neuropathy]. Stress-optic-neuropathy risk was calculated from two indices: a newly derived diastolic-ocular-perfusion-pressure cut-point ≥68 mmHg relating to the stress-phenotype; combined with an established cup-to-disk ratio cut-point ≥0.3. Higher stress-optic-neuropathy (39% vs. 17%) and hypertension (73% vs. 16%) prevalence was observed in the stress-phenotype cases vs. controls. Elevated diastolic-ocular-perfusion-pressure, indicating hypoperfusion, was related to arterial narrowing and trend for ischemia increases in the stress-phenotype. Ischemia in the stress-phenotype at baseline, follow-up and three-year changes was related to consistent inflammation (TNF-α and cytokine-interleukin-17-receptor-A), neuron-specific-enolase increases, consistent apoptosis (chitinase-3-like protein 1, low beta-nerve-growth-factor), glial-fibrillary-acidic-protein decreases, elevated viscosity, vein widening as risk marker of endothelial dysfunction in the blood-retinal barrier, lower vein count, and elevated stress-optic-neuropathy. The stress-phenotype and related neurodegenerative signs of ongoing brain ischemia, apoptosis and endothelial dysfunction compromised blood-retinal barrier permeability and optic nerve integrity. In fact, the stress-phenotype could identify persons at high risk of neurodegeneration to indicate a neurodegenerative condition.


Assuntos
Doenças Neurodegenerativas , Fator de Necrose Tumoral alfa , Humanos , Fator de Necrose Tumoral alfa/metabolismo , Estudos Prospectivos , Estresse Psicológico , Retina/metabolismo , Doenças Neurodegenerativas/metabolismo , Isquemia/metabolismo , Inflamação/metabolismo , Fosfopiruvato Hidratase/metabolismo
2.
Brain Behav Immun Health ; 2: 100027, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38377420

RESUMO

Background: Psychobiological processes linking stress and vascular diseases remain poorly understood. The retina and the brain share a common embryonic-diencephalon origin and blood-barrier physiology e.g. ongoing ischemia facilitates S100B release with astrocytic activity and glial-fibrillary-acidic-protein expression (GFAP). However, GFAP decreases revealed astrocyte pathology in the prefrontal cortex of depression/suicide cases; and might be a key mechanism in stress - disease pathways. Methods: A chronic emotional stress phenotype independent of age, ethnicity or sex was used to stratify the current prospective cohort (N â€‹= â€‹359; aged 46 â€‹± â€‹9 years) into Stress (N â€‹= â€‹236) and no-Stress groups (N â€‹= â€‹123). Prospective data for glia ischemia risk markers were obtained, including 24 â€‹h BP, fasting S100B, GFAP, HbA1C and tumor-necrosis-factor-α (TNF-α). At 3-yr follow-up: diastolic-ocular-perfusion-pressure (indicating hypo-perfusion risk) was measured and retinal vessel calibers were quantified from digital images in the mydriatic eye. Results: Higher hypertension (75% vs. 16%), diabetes (13% vs. 0%) and retinopathy (57% vs. 45%) prevalence was observed in Stress compared to no-Stress individuals. Stressed individuals had consistently raised S100B, TNF-α, HbA1C and higher diastolic-ocular-perfusion-pressure, but decreases in GFAP and GFAP:S100B. Furthermore stroke risk markers, arterial narrowing and venous widening were associated with consistently raised S100B, GFAP:S100B (p â€‹= â€‹0.060), TNF-α and higher diastolic-ocular-perfusion-pressure [Adj. R2 0.39-0.41, p â€‹≤ â€‹0.05]. No retinal-glia associations were evident in the no-Stress group. Conclusions: Retinal-glia ischemia and inflammation was induced by chronic stress. Persistent higher inflammation and S100B with GFAP decreases further reflected stress-induced astrocyte pathology in the human retina. It is recommended to increase awareness on chronic stress and susceptibility for brain ischemia.

3.
Adv Exp Med Biol ; 956: 497-510, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27421968

RESUMO

Globally most interventions focus on improving lifestyle habits and treatment regimens to combat hypertension as a non-communicable disease (NCD). However, despite these interventions and improved medical treatments, blood pressure (BP) values are still on the rise and poorly controlled in sub-Saharan Africa (SSA). Other factors contributing to hypertension prevalence, such as chronic emotional stress, might provide some insight for future health policy approaches.Currently, Hypertension Society guidelines do not mention emotional stress as a probable cause for hypertension. Recently the 2014 World Global Health reports, suggested that African governments should consider using World Health Organization hypertension data as a proxy indicator for social well-being. However, the possibility that a stressful life and taxing environmental factors might disturb central neural control of BP regulation has largely been ignored in SSA.Linking emotional stress to vascular dysregulation is therefore one way to investigate increased cardiometabolic challenges, neurotransmitter depletion and disturbed hemodynamics. Disruption of stress response pathways and subsequent changes in lifestyle habits as ways of coping with a stressful life, and as probable cause for hypertension prevalence in SSA, may be included in future preventive measures. We will provide an overview on emotional stress and central neural control of BP and will include also implications thereof for clinical practice in SSA cohorts.


Assuntos
População Negra/psicologia , Pressão Sanguínea , Encéfalo/fisiopatologia , Hipertensão/etnologia , Estresse Psicológico/etnologia , África Subsaariana/epidemiologia , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/etnologia , Dieta/efeitos adversos , Dieta/etnologia , Humanos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Hipertensão/psicologia , Estilo de Vida/etnologia , Saúde Mental , Razão de Chances , Prevalência , Prognóstico , Medição de Risco , Fatores de Risco , Comportamento Sedentário/etnologia , Fumar/efeitos adversos , Fumar/etnologia , Estresse Psicológico/diagnóstico , Estresse Psicológico/fisiopatologia , Estresse Psicológico/psicologia
4.
Psychosom Med ; 77(1): 26-32, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25469684

RESUMO

OBJECTIVE: Telomere length is a marker of biological aging that has been linked to cardiovascular disease risk. The black South African population is witnessing a tremendous increase in the prevalence of cardiovascular disease, part of which might be explained through urbanization. We compared telomere length between black South Africans and white South Africans and examined which biological and psychosocial variables played a role in ethnic difference in telomere length. METHODS: We measured leukocyte telomere length in 161 black South African teachers and 180 white South African teachers aged 23 to 66 years without a history of atherothrombotic vascular disease. Age, sex, years having lived in the area, human immunodeficiency virus (HIV) infection, hypertension, body mass index, dyslipidemia, hemoglobin A1c, C-reactive protein, smoking, physical activity, alcohol abuse, depressive symptoms, psychological distress, and work stress were considered as covariates. RESULTS: Black participants had shorter (median, interquartile range) relative telomere length (0.79, 0.70-0.95) than did white participants (1.06, 0.87-1.21; p < .001), and this difference changed very little after adjusting for covariates. In fully adjusted models, age (p < .001), male sex (p = .011), and HIV positive status (p = .023) were associated with shorter telomere length. Ethnicity did not significantly interact with any covariates in determining telomere length, including psychosocial characteristics. CONCLUSIONS: Black South Africans showed markedly shorter telomeres than did white South African counterparts. Age, male sex, and HIV status were associated with shorter telomere length. No interactions between ethnicity and biomedical or psychosocial factors were found. Ethnic difference in telomere length might primarily be explained by genetic factors.


Assuntos
População Negra , Docentes , Leucócitos/metabolismo , Telômero/metabolismo , População Branca , Adulto , Idoso , Alcoolismo , Proteína C-Reativa , Depressão , Dislipidemias , Feminino , Hemoglobinas Glicadas , Infecções por HIV , Humanos , Hiperglicemia , Hipertensão , Masculino , Pessoa de Meia-Idade , Atividade Motora , Obesidade , Fumar , África do Sul , Estresse Psicológico , Homeostase do Telômero , Adulto Jovem
5.
J Hypertens ; 30(12): 2387-94, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23111623

RESUMO

BACKGROUND: Hypertension and increased blood glucose are associated with subclinical kidney damage, atherosclerosis and with low testosterone values. Low testosterone in men is often accompanied by increased levels of estradiol. OBJECTIVES AND METHODS: In this study, the association between estradiol, subclinical kidney damage and atherosclerosis in African and white men in a South African cohort was investigated. Cardiovascular variables were studied by means of B-mode ultrasound and ambulatory blood pressure (BP) monitoring. The sex hormones and other biochemical values were measured from fasting venous blood and overnight urine samples. The ethnic groups were stratified into low and high testosterone groups by means of median split. RESULTS: The low testosterone African group demonstrated a higher cardiovascular risk compared with the low testosterone white men with 91% being hypertensive and having increased albumin-to-creatinine ratio (ACR), left carotid intima-media thickness (L-CIMTf) and estradiol-to-testosterone ratio. In the low-testosterone African men, estradiol explained 33% of the variance in ACR, whereas the estradiol-to-testosterone ratio explained 22% of the variance in L-CIMTf, respectively. Estradiol-to-testosterone ratio was positively associated with ACR in the low testosterone whites. CONCLUSION: We conclude that increased levels of estradiol may play a role in the development of subclinical kidney damage in both African and white men as well as atherosclerosis in low-testosterone African men.


Assuntos
Aterosclerose/etnologia , Aterosclerose/epidemiologia , População Negra , Estradiol/sangue , Nefropatias/etnologia , Nefropatias/epidemiologia , Testosterona/sangue , População Branca , Adulto , Idoso , Albuminas/metabolismo , Aterosclerose/metabolismo , Biomarcadores/sangue , Estudos de Coortes , Creatinina/metabolismo , Endotélio Vascular/fisiopatologia , Humanos , Nefropatias/metabolismo , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , África do Sul/epidemiologia
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