Impact of arterial hypertension on the eye

OCTA evaluates changes in retinal microvasculature in renal hypertension patients

The objective of this study is to utilize optical coherence tomography angiography (OCTA) techniques for the purpose of identifying abnormalities in retinal and conjunctival vascular density among patients afflicted with renal hypertension. From October 2022 to October 2023, a cohort of sixteen patients diagnosed with renal hypertension (RH), comprising a total of 32 eyes, was selected from the Department of Nephrology at the First Affiliated Hospital of Nanchang University. Concurrently, a group of sixteen healthy individuals, carefully matched in characteristics, was recruited from volunteers at the Ophthalmology Research Center and designated as the healthy controls (HCs) group. Optical coherence tomography angiography was employed to assess and examine the superficial vascular plexus (SVP) and deep vascular plexus (DVP) of the macular retina in both eyes. Subsequently, a comparative analysis was conducted between the two groups, focusing on the superficial and deep retinal microvessels (MIR), macrovascular (MAR), and total microvascular (TMI). The present study employed the central annuli segmentation method (C1-C6), the hemispheric segmentation method (SL, IL, SR, IR), and the Early Treatment Diabetic Retinopathy Study (S, I, L, R) to evaluate deviations in retinal blood vessel density. The investigation aimed to examine the association between blood vessel density and TMI in conjunctival capillaries. A statistically significant difference (p < 0.05) in macular retinal vascular density was observed between the two groups based on the OCTA data. Specifically, in SVP, the density of TMI, MIR, and MAR in the RH group was significantly lower compared to the HCs group (p < 0.05). Additionally, the deep density of TMI and MIR in DVP of the RH group was significantly lower than that of the HCs group (p < 0.05). Furthermore, using the hemispheric segmentation method, both the superficial and deep retina showed a significant reduction in the density of SL, SR and IL regions (p < 0.05). In the ETDRS method, there was a significant decrease in superficial and deep retinal S, I, and L in the RH group (p < 0.05). When applying the central annuli segmentation methods, the RH group exhibited a significant decrease in the superficial retinal C1-3 region (p < 0.05) and a noticeable reduction in the deep retina in the C1-4 region (p < 0.05). Furthermore, a higher positive likelihood ratio was observed in the deep SL and superficial C2 region. There was a positive correlation between conjunctival capillary density and the region of TMI in depth. The results of the OCTA investigation revealed a significant disparity in the density of superficial and deep retinal blood vessels between RH group and the HCs group. Additionally, a notable correlation was observed between the depth of TMI and the density of conjunctival capillaries. These findings highlight the potential of retinal OCTA as a valuable tool for early detection and image-assisted diagnosis of retinopathy progression in patients with RH.

Retinal microcirculation: A window into systemic circulation and metabolic disease

The retinal microcirculation system constitutes a unique terminal vessel bed of the systemic circulation, and its perfusion status is directly associated with the neural function of the retina. This vascular network, essential for nourishing various layers of the retina, comprises two primary microcirculation systems: the retinal microcirculation and the choroidal microcirculation, with each system supplying blood to distinct retinal layers and maintaining the associated neural function. The blood flow of those capillaries is regulated via different mechanisms. However, a range of internal and external factors can disrupt the normal architecture and blood flow within the retinal microcirculation, leading to several retinal pathologies, including diabetic retinopathy, macular edema, and vascular occlusions. Metabolic disturbances such as hyperglycemia, hypertension, and dyslipidemia are known to modify retinal microcirculation through various pathways. These alterations are observable in chronic metabolic conditions like diabetes, coronary artery disease, and cerebral microvascular disease due to advances in non-invasive or minimally invasive retinal imaging techniques. Thus, examination of the retinal microcirculation can provide insights into the progression of numerous chronic metabolic disorders. This review discusses the anatomy, physiology and pathophysiology of the retinal microvascular system, with a particular emphasis on the connections between retinal microcirculation and systemic circulation in both healthy states and in the context of prevalent chronic metabolic diseases.

Visual Impairment and Its Associated Factors Among Hypertensive Patients in Amhara Region Referral Hospitals, Ethiopia

Background

Visual impairment is one of the most common long-term effects of high blood pressure. It affects one's quality of life, independence, and mobility. There is a paucity of information regarding the prevalence of visual impairment due to hypertension in Ethiopia. Therefore, this study aimed to determine the prevalence of visual impairment and its associated factors among hypertensive patients in referral hospitals of the Amhara region, Ethiopia, 2021.

Methods

An institution-based cross-sectional study was conducted among 423 study participants, which were selected by systematic random sampling technique. Data were collected by using an interviewer-administered structured questionnaire and physical measurements. The collected data were entered into Epi-data version 4.6. Then, exported into SPSS Version 26 for analysis. The crude and adjusted odds ratios and 95% Confidence intervals were calculated. Both bivariable and multivariable logistic regression analyses were done. Variables with a p-value of ≤0.05 were stated as significantly associated with visual impairment.

Results

The overall prevalence of visual impairment among hypertensive patients was 32.4% (95% CI: 27.9-37.9). Duration of hypertension ≥ 5 years (AOR =3.06, 95% CI: 1.86-4.95), history of ocular trauma (AOR =2.50, 95% CI: 1.3-4.73), and ever alcohol drinking (AOR = 2.72, 95% CI: 1.32-5.62) were significantly associated with visual impairment.

Conclusion

Nearly one-third of hypertensive patients were visually impaired from the study participants. Duration of hypertension ≥5 years, history of ocular trauma, and ever alcohol drinking was significantly associated with visual impairment among hypertensive patients. Therefore, in addition to providing medical care and follow-up services for hypertension patients, health education is needed for early and proper management of visual impairment, and to decrease their level of alcohol consumption. Furthermore, better to do this study by prospective cohort study design to identify cause-and-effect relationships.

Prevalence of venous loops and association with retinal ischemia in diabetic retinopathy using widefield swept-source OCT angiography

PURPOSE

To investigate the prevalence and clinical characteristics of diabetic patients with retinal venous loops (RVLs) and to assess the association with retinal ischemia using widefield swept-source optical coherence tomography angiography (WF SS-OCTA).

METHODS

In this retrospective, cross-sectional study, a total of 195 eyes of 132 diabetic patients (31 eyes with no diabetic retinopathy (DR), 76 eyes with nonproliferative DR (NPDR), and 88 eyes with proliferative DR (PDR)) were imaged with WF SS-OCTA using Angio 6 × 6 mm and Montage 15 × 15 mm scans. Quantitative ischemia-related parameters, including ischemia index (ratio of nonperfusion area to total retinal area), foveal avascular zone (FAZ), and neovascularization features, were evaluated. RVLs were classified as type I or type II according to the branching level of the feeder vessel. A multivariate generalized estimating equations (GEE) logistic regression model was used to analyze the association of systemic parameters and ischemia-related metrics with RVLs in PDR eyes.

RESULTS

Forty-eight RVLs were identified in 22 eyes (11.28%). The prevalence of RVLs was higher in PDR compared to NPDR eyes (21.59% vs. 3.95%, P < 0.05). Type II RVLs accounted for a higher proportion than type I (89.58% vs. 10.42%, P < 0.001). RVLs were more likely to originate from superior (vs. inferior) and temporal (vs. nasal) veins (P < 0.05). The GEE model showed that neovascularization (NV) flow area and diastolic blood pressure were associated with RVLs in the PDR group (P < 0.05).

CONCLUSION

WF SS-OCTA is useful for the identification of RVLs in patients with DR. NV flow area and diastolic blood pressure were associated with the presence of RVLs in eyes with PDR. Ischemia index, FAZ, and other WF SS-OCTA parameters were not associated with RVLs. Further longitudinal studies are needed to identify the role of RVLs in DR progression.

Association between Food Insecurity and Vision Impairment among Older Adults: A Pooled Analysis of Data from Six Low- and Middle-Income Countries

OBJECTIVES

Food insecurity has gained attention as a potential risk factor for vision impairment. However, research on this topic is limited. This objective of this study was to investigate the relationship between food insecurity and visual impairment among adults aged 50 years or older using data from six low-and middle-income countries (LMIC).

DESIGN AND SETTING

Data from the longitudinal Study on global AGEing and adult health (SAGE) were analyzed in a community-based, cross-sectional, and nationally representative sample.

PARTICIPANTS

Adults aged 50 years or older from six low- and middle-income countries (LMICs) including China, India, Mexico, Russia, South Africa, and Ghana.

MEASUREMENTS

Food insecurity was evaluated using a questionnaire comprised of two questions that addressed the frequency of eating inadequately and hunger due to a lack of food in last 12 months. Distance and/or near vision impairment was considered as a visual acuity score of less than 6/18 in the eye with better vision.

RESULTS

The analytical sample consisted of 29,804 adults (mean (SD) for age: 63.2 (9.54) years; 54.3% female). The prevalence of food insecurity, near vision and distance vision impairment in the sample was 16.4%, 36.7%, and 13.9%, respectively. Adjusted pooled analyses across countries revealed a significant association between food insecurity and distance (OR: 1.16; 95% CI: 1.01, 1.33; P=0.04, significant individually in India and South Africa) and near (OR: 1.12; 95% CI: 1.02, 1.22; P=0.01, significant individually in South Africa) vision impairment, and a between-country heterogeneity of 46.30% and 25.99%, respectively.

CONCLUSION

Food insecurity was associated with both distance and near vision impairment in adults aged 50 years or older across six LMIC. Food policies and intervention programs targeted at decreasing food insecurity in vulnerable households are essential.

Influence of Sedentary Behaviour Interventions on Vascular Functions and Cognitive Functions in Hypertensive Adults-A Scoping Review on Potential Mechanisms and Recommendations

Since the workplace has become desk-based and leisure time has become dominated by digital relaxation modes, the world is moving at a pace where physical activity has become a time-bound routine. The negative effects of extended sitting are a global concern since the workforce is becoming more desk based. There is a dearth of reviews that may link the knowledge on the effects of sedentary behaviour on hypertension and its accompanying damage to the brain and blood vessels and provide a future scope for the investigations connected to the relationship between sedentary behaviour and hypertension. Methods: Based on the database search and extensive research we did, we found studies that concentrated on the adverse effects of sedentary behaviour in association with blood pressure, cognitive decline and brain damage on adults. Results: We extracted 12 articles out of 20,625. We identified the potential adverse effects of sedentary behaviour, methods to reduce sedentary behaviour and the positive changes on health due to the interventions introduced. Sedentary lifestyle has shown a decline in human health. However, the visible symptoms presented later in life makes it very important to know the areas of decline and look for ways to curb the decline or procrastinate it.

A review of risk factors for retinal vein occlusions

INTRODUCTION

Risk factors for retinal vein occlusion have been extensively studied, with varying population sizes. Smaller populations result in less certain measures of associations. The present review included studies with a relevant population size to identify clinically relevant risk factors for retinal vein occlusion. Understanding the risk factors of retinal vein occlusion is important for the management of these patients.

AREAS COVERED

A comprehensive literature review was conducted through a systematic literature search in PubMed and Embase. Additional studies were selected from cross references in the assessed studies. Weighted effect measures were calculated for all included risk factors.Risk factors associated with retinal vein occlusion included cardiovascular diseases, eye diseases, systemic diseases, medical interventions, and sociodemographic factors.

EXPERT OPINION

This review provided an extensive overview of a wide variety of risk factors increasing the risk of developing retinal vein occlusion. The severity of the identified risk factors indicated that these patients have been in contact with the health care system before their retinal vein occlusion event. Therefore, the clinical course for patients with retinal vein occlusion may benefit from a multidisciplinary collaboration between ophthalmologists and especially cardiologists.

Review: The Development of Risk Factors and Cytokines in Retinal Vein Occlusion

Retinal vein occlusion (RVO) is the second most prevalent retinal disease. Despite this, the pathogenic mechanisms and risk factors are not entirely clear. In this article, we review recent publications on the classification, pathogenesis, risk factors, ischemic changes, cytokines, and vital complications of RVO. Risk factors and cytokines are important for exploring the mechanisms and new treatment targets. Furthermore, risk factors are interrelated, making RVO mechanisms more complex. Cytokines act as powerful mediators of pathological conditions, such as inflammation, neovascularization, and macular edema. This review aims to summarize the updated knowledge on risk factors, cytokines of RVO and signaling in order to provide valuable insight on managing the disease.

Hypertension as a risk factor for retinal vein occlusion in menopausal women: A nationwide Korean population-based study

Retinal vein occlusion (RVO) is an important cause of blindness. Hypertension is a well-known risk factor for RVO. Although the prevalence of hypertension increases in women after menopause, the relationship between blood pressure and RVO in women before and after menopause has not been studied in detail.We retrospectively analyzed 2,619,206 patients from the Korean National Health Insurance System database. A Cox proportional hazard regression model was used to evaluate the independent association between blood pressure and the risk of RVO development and identify differences between premenopausal and postmenopausal women.The incidence of RVO was higher among postmenopausal women than in premenopausal women. In the model adjusted for socioeconomic and clinical variables, there was an association between blood pressure and RVO development in premenopausal and postmenopausal women; however, this was stronger than premenopausal women.Both systolic and diastolic blood pressure are associated with an increased risk of RVO, and their effects are more potent in premenopausal women than postmenopausal women. Thus, comprehensive management of hypertension in premenopausal women is essential to reduce the risk of RVO.

Long-term inhibition of UCHL1 decreases hypertension and retinopathy in spontaneously hypertensive rats

OBJECTIVE

To investigate the role of the deubiquitinase ubiquitin C-terminal hydrolase L1 (UCHL1) in hypertension and retinopathy in the spontaneously hypertensive rat (SHR).

METHODS

Wistar-Kyoto (WKY) rats and SHRs were administered the UCHL1 inhibitor LDN57444 (20 μg/kg/day) for 4 months. Pathological changes were detected with hematoxylin and eosin, immunofluorescence, and dihydroethidium staining. The mRNA and protein expression of UCHL1 were examined by real-time PCR and immunoblotting analysis.

RESULTS

At 6 months of age, SHRs showed significantly increased mRNA and protein levels of UCHL1 in the retina compared with WKY rats. Moreover, SHRs exhibited significantly increased central retinal thickness, inflammation, and reactive oxygen species production compared with WKY rats, and these effects were markedly attenuated by systemic administration of the UCHL1 inhibitor LDN57444. The beneficial effects of LDN57444 were possibly associated with reduced blood pressure and the inactivation of several signaling pathways.

CONCLUSION

UCHL1 is involved in hypertension and retinopathy in SHRs, suggesting that UCHL1 may be used as a potential therapeutic target for treating hypertensive retinopathy.

Effects of Caloric Restriction Diet on Arterial Hypertension and Endothelial Dysfunction

The most common manifestation of cardiovascular (CV) diseases is the presence of arterial hypertension (AH), which impacts on endothelial dysfunction. CV risk is associated with high values of systolic and diastolic blood pressure and depends on the presence of risk factors, both modifiable and not modifiable, such as overweight, obesity, physical exercise, smoking, age, family history, and gender. The main target organs affected by AH are the heart, brain, vessels, kidneys, and eye retina. AH onset can be counteracted or delayed by adopting a proper diet, characterized by a low saturated fat and sodium intake, a high fruit and vegetable intake, a moderate alcohol consumption, and achieving and maintaining over time the ideal body weight. In this review, we analyzed how a new nutritional approach, named caloric restriction diet (CRD), can provide a significant reduction in blood pressure values and an improvement of the endothelial dysfunction. In fact, CRD is able to counteract aging and delay the onset of CV and neurodegenerative diseases through the reduction of body fat mass, systolic and diastolic values, free radicals production, and oxidative stress. Currently, there are few studies on CRD effects in the long term, and it would be advisable to perform observational studies with longer follow-up.

GPR174 suppression attenuates retinopathy in angiotensin II (Ang II)-treated mice by reducing inflammation via PI3K/AKT signaling

Hypertension is closely associated with eye diseases, including hypertensive retinopathy. However, the molecular mechanism controlling the progression of hypertensive retinopathy remains poorly understood. G-Protein Coupled Receptor 174 (GPR174) is expressed in various tissues, and plays a critical role in regulating immune and inflammatory responses. However, if GPR174 is involved in angiotensin II (Ang II)-induced retinopathy is still unclear. In this study, hypertensive retinopathy was induced by Ang II infusion in the wild type (GPR174^+/+) and GPR174 knockout (GPR174^-/-) mice. Clinical data indicated that GPR174 levels were markedly up-regulated in serum of patients with hypertension (HP) or hypertensive retinopathy (HR), along with increased trypsin-like activity. Similar changes of GRP174 and trypsin-like activity were observed in Ang II-infused mice. Furthermore, Ang IIsignificantly increased the central retinal thickness, vascular permeability and inflammatory response in GPR174^+/+ micewhen compared with the saline GPR174^+/+ mice. Of note, these effects were markedly alleviated by the knockout ofGPR174 in Ang II-treated mice. Consistently, vascular endothelial growth factor (VEGF) expression levels in retinal tissue were also stimulated by Ang II, which were clearly attenuated by GPR174^-/-. In addition, phosphatidylinositol 3-kinase (PI3 K)/AKT and nuclear factor-κB (NF-κB) signaling pathways were markedly activated in retinas of Ang II-infused GPR174^+/+ mice, whereas being greatly ameliorated by GPR174^-/-. The in vitro data showed that pre-treatment of PI3 K/AKT specific inhibitor LY294002 remarkably abrogated GPR174 over-expression-accelerated expression levels of Iba-1, tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 in lipopolysaccharide (LPS)-incubated retinal microglial cells.Furthermore, in LPS-exposed retinal microglial cells, PI3 K/AKT and NF-κB pathways were further promoted by GPR174 over-expression, which were significantlyabolished by LY294002. Thus, GPR174 might be a positive meditator of inflammation, contributing to Ang II-induced retinopathy by activating PI3 K/AKT signaling, and could be considered as a novel therapeutic target for the treatment of hypertensive retinopathy.

Long-Term Follow-Up Changes of Central Choroidal Thickness Thinning after Repeated Anti-VEGF Therapy Injections in Patients with Central Retinal Vein Occlusion-Related Macular Edema with Systemic Hypertension

PURPOSE

We investigated the thinning of central choroidal thickness (CCT) following intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) drugs to treat central retinal vein occlusion (CRVO)-related macular edema in patients with and without systemic hypertension (HT) to assess the influence of repeated anti-VEGF therapy and HT on the choroid in CRVO eyes.

METHODS

We conducted a retrospective study involving 27 patients with CRVO-related macular edema from January 2014 to July 2017, with follow-ups exceeding 18 months. Visual acuity (VA), central retinal thickness (CRT), and CCT were evaluated before and after initial anti-VEGF drug treatment during follow-up.

RESULTS

The mean follow-up period was 35.2 months. Seventeen (63.0%) patients had HT. At 1 month after treatment, VA had improved in 21 (77.8%) patients, and CRT had decreased in 25 (92.6%). At the final visit, 22 (81.5%) showed improved VA, 19 (70.4%) had resolved macular edema, and the CCT had gradually become thinner with additional drug injections in all the patients. Furthermore, the mean CCT in HT patients (209.0 µm) was significantly lower than in non-HT patients (256.1 µm), and the mean injections were 7.8 and 5.3, respectively (p = 0.2067).

CONCLUSION

The CCTs were thinner in eyes with HT than in eyes without HT both before and after the repeated anti-VEGF injections.

Ablation of Immunoproteasome β5i Subunit Suppresses Hypertensive Retinopathy by Blocking ATRAP Degradation in Mice

Inflammation is associated with retinal diseases. Our recent data demonstrate that immunoproteasome catalytic subunit β2i contributes to angiotensin II (Ang II)-induced retinopathy in mice. Here, we investigated the role of another catalytic subunit β5i in regulating retinopathy and its underlying mechanisms. We induced a murine model of retinopathy by infusing Ang II (3,000 ng/kg/min) for 3 weeks into wild-type (WT) mice, β5i-knockout (KO) mice, or WT mice injected with either adenovirus-expressing β5i (Ad-β5i) or angiotensin II type 1 receptor (AT1R)-associated protein (Ad-ATRAP), which inhibits AT1R. The β5i expression and chymotrypsin-like activity were most significantly elevated in Ang II-infused retinas and serum from patients with hypertensive retinopathy. Moreover, Ang II infusion-induced retinopathy was markedly attenuated in β5i-KO mice but aggravated in Ad-β5i-injected mice. Accordingly, β5i KO markedly restored Ang II-induced downregulation of ATRAP and activation of AT1R downstream mediators, which was further enhanced in Ad-β5i-injected mice. Interestingly, overexpression of ATRAP significantly abrogated Ang II-induced retinopathy in Ad-β5i-injected mice. This study found that β5i promoted Ang II-induced retinopathy by promoting ATRAP degradation and activation of AT1R-mediated signals.

The immunoproteasome subunit LMP10 mediates angiotensin II-induced retinopathy in mice

Inflammation has been implicated in a variety of retinal diseases. The immunoproteasome plays a critical role in controlling inflammatory responses, but whether activation of immunoproteasome contributes to angiotensin II (Ang II)-induced retinopathy remains unclear. Hypertensive retinopathy (HR) was induced by infusion of Ang II (3000 ng/kg/min) in wild-type (WT) and immunoproteasome subunit LMP10 knockout (KO) mice for 3 weeks. Changes in retinal morphology, vascular permeability, superoxide production and inflammation were examined by pathological staining. Our results showed that immunoproteasome subunit LMP10 expression and its trypsin-like activity were significantly upregulated in the retinas and serum of Ang II-infused mice and in the serum from patients with hypertensive retinopathy. Moreover, Ang II-infused WT mice showed an increase in the central retinal thickness, vascular permeability, reactive oxygen species (ROS) production and inflammation compared with saline controls, and these effects were significantly attenuated in LMP10 KO mice, but were aggravated in mice intravitreally injected with rAAV2-LMP10. Interestingly, administration of IKKβ specific inhibitor IMD-0354 remarkably blocked an Ang II-induced increase in vascular permeability, oxidative stress and inflammation during retinopathy. Mechanistically, Ang II-induced upregulation of LMP10 promoted PTEN degradation and activation of AKT/IKK signaling, which induced IkBα phosphorylation and subsequent degradation ultimately leading to activation of NF-kB target genes in retinopathy. Therefore, this study provided novel evidence demonstrating that LMP10 is a positive regulator of NF-kB signaling, which contributes to Ang II-induced retinopathy. Strategies for inhibiting LMP10 or IKKβ activity in the eye could serve as a novel therapeutic target for treating hypertensive retinopathy.

Alterations of Ocular Hemodynamics Impair Ophthalmic Vascular and Neuroretinal Function

Hypertension is associated with numerous diseases, but its direct impact on the ocular circulation and neuroretinal function remains unclear. Herein, mouse eyes were challenged with different levels of hemodynamic insult via transverse aortic coarctation, which increased blood pressure and flow velocity by 50% and 40%, respectively, in the right common carotid artery, and reduced those parameters by 30% and 40%, respectively, in the left common carotid artery. Blood velocity in the right central retinal artery gradually increased up to 40% at 4 weeks of transverse aortic coarctation, and the velocity in the left central retinal artery gradually decreased by 20%. The fundus and retinal architecture were unaltered by hemodynamic changes. Endothelium-dependent vasodilations to acetylcholine and adenosine were reduced only in right (hypertensive) ophthalmic arteries. Increased cellularity in the nerve fiber/ganglion cell layers, enhanced glial fibrillary acidic protein expression, and elevated superoxide level were found only in hypertensive retinas. The electroretinogram showed decreased scotopic b-waves in the hypertensive eyes and decreased scotopic oscillatory potentials in both hypertensive and hypotensive eyes. In conclusion, hypertension sustained for 4 weeks causes ophthalmic vascular dysfunction, retinal glial cell activation, oxidative stress, and neuroretinal impairment. Although ophthalmic vasoregulation is insensitive to hypotensive insult, the ocular hypoperfusion causes neuroretinal dysfunction.

Hypertensive retinopathy in a transgenic angiotensin-based model

Severe hypertension destroys eyesight. The RAS (renin-angiotensin system) may contribute to this. This study relied on an established angiotensin, AngII (angiotensin II)-elevated dTGR (double-transgenic rat) model and same-background SD (Sprague-Dawley) rat controls. In dTGRs, plasma levels of AngII were increased. We determined the general retinal phenotype and observed degeneration of ganglion cells that we defined as vascular degeneration. We also inspected relevant gene expression and lastly observed alterations in the outer blood-retinal barrier. We found that both scotopic a-wave and b-wave as well as oscillatory potential amplitude were significantly decreased in dTGRs, compared with SD rat controls. However, the b/a-wave ratio remained unchanged. Fluorescence angiography of the peripheral retina indicated that exudates, or fluorescein leakage, from peripheral vessels were increased in dTGRs compared with controls. Immunohistological analysis of blood vessels in retina whole-mount preparations showed structural alterations in the retina of dTGRs. We then determined the general retinal phenotype. We observed the degeneration of ganglion cells, defined vascular degenerations and finally found differential expression of RAS-related genes and angiogenic genes. We found the expression of both human angiotensinogen and human renin in the hypertensive retina. Although the renin gene expression was not altered, the AngII levels in the retina were increased 4-fold in the dTGR retina compared with that in SD rats, a finding with mechanistic implications. We suggest that alterations in the outer blood-retinal barrier could foster an area of visual-related research based on our findings. Finally, we introduce the dTGR model of retinal disease.

A nanostructured genosensor for the early diagnosis of systemic arterial hypertension

The rapid progress of nanomedicine, especially in areas related to medical imaging and diagnostics, has motivated the development of new nanomaterials that can be combined with biological materials for specific medical applications. One such area of research involves the detection of specific DNA sequences for the early diagnosis of genetic diseases, using nanoparticles-containing genosensors. Typical genosensors devices are based on the use of sensing electrodes - biorecognition platforms - containing immobilized capture DNA probes capable of hybridizing with specific target DNA sequences. In this paper we show that upon an appropriate design of the biorecognition platform, efficient sandwich-type genosensors based upon DNA-AuNPs nanocomplexes can be efficiently applied to the detection of a Systemic Arterial Hypertension (SAH) polymorphism located in intron 16 of the Angiotensin-converter enzyme (ACE) gene. Since SAH is intimately related to heart diseases, especially blood hypertension, its early detection is of great biomedical interest. The biorecognition platforms were assembled using mixed self-assembled monolayers (SAMmix), which provided the immobilization of organized architectures with molecular control. Detection of the DNA target sequence at concentrations down to 1 nM was carried out using electrochemical impedance spectroscopy (EIS). We show that the use of EIS combined with specific nanobiocomplexes represents an efficient method for the unambiguous detection of complementary DNA hybridization for preventative nanomedicine applications.

Healthy lifestyle in the primordial prevention of cardiovascular disease among young women

BACKGROUND

Overall mortality rates from coronary heart disease (CHD) in the United States have declined in recent decades, but the rate has plateaued among younger women. The potential for further reductions in mortality rates among young women through changes in lifestyle is unknown.

OBJECTIVES

The aim of this study was to estimate the proportion of CHD cases and clinical cardiovascular disease (CVD) risk factors among young women that might be attributable to poor adherence to a healthy lifestyle.

METHODS

A prospective analysis was conducted among 88,940 women ages 27 to 44 years at baseline in the Nurses' Health Study II who were followed from 1991 to 2011. Lifestyle factors were updated repeatedly by questionnaire. A healthy lifestyle was defined as not smoking, a normal body mass index, physical activity ≥ 2.5 h/week, television viewing ≤ 7 h/week, diet in the top 40% of the Alternative Healthy Eating Index-2010, and 0.1 to 14.9 g/day of alcohol. To estimate the proportion of CHD and clinical CVD risk factors (diabetes, hypertension, and hypercholesterolemia) that could be attributed to poor adherence to a healthy lifestyle, we calculated the population-attributable risk percent.

RESULTS

During 20 years of follow-up, we documented 456 incident CHD cases. In multivariable-adjusted models, nonsmoking, a healthy body mass index, exercise, and a healthy diet were independently and significantly associated with lower CHD risk. Compared with women with no healthy lifestyle factors, the hazard ratio for CHD for women with 6 lifestyle factors was 0.08 (95% confidence interval: 0.03 to 0.22). Approximately 73% (95% confidence interval: 39% to 89%) of CHD cases were attributable to poor adherence to a healthy lifestyle. Similarly, 46% (95% confidence interval: 43% to 49%) of clinical CVD risk factor cases were attributable to a poor lifestyle.

CONCLUSIONS

Primordial prevention through maintenance of a healthy lifestyle among young women may substantially lower the burden of CVD.

Treatment of systemic hypertension is important for improvement of macular edema associated with retinal vein occlusion

Background

We report our findings in three cases of unilateral macular edema associated with retinal vein occlusion (RVO) that improved after successful treatment of systemic hypertension alone.

Methods

All three cases had systemic hypertension but no diabetes mellitus or other ocular diseases associated with macular edema. All patients were treated only with medication for systemic hypertension. Optical coherence tomography was performed to determine the foveal thickness before and after treatment.

Results

Case one was a 72-year-old woman with a central RVO who had macular edema in her left eye and a visual acuity (VA) of 20/50. Her blood pressure (BP) was 169/96 mmHg. One month after the initiation of a calcium blocker to treat her systemic hypertension, her BP was decreased, macular edema was reduced, and her VA improved to 20/20. Case two was a 62-year-old woman with branch RVO. Her VA was 20/40 and her BP was 165/97 mmHg. Six weeks after initiation of medication to treat her systemic hypertension, her RVO-related macular edema had decreased and her VA improved to 20/20. Case three was a 71-year-old man with branch RVO. His VA was 20/50 and his BP was 165/87 mmHg. One month after initiation of treatment for systemic hypertension, his RVO-related macular edema had disappeared and his VA improved to 20/20. All three cases had nonischemic RVO by fluorescein angiography, and they did not develop ischemic changes for at least 1 year.

Conclusion

The reduction of macular edema following a decrease in the systemic hypertension suggests that the edema was most likely caused by leakage of fluids from the blood vessels. We recommend that the blood pressure should be measured in all patients with macular edema before initiating intravitreal anti-VEGF therapy.

[Hypertension-related eye disorders]

Hypertension affects a significant proportion of the population, however, it is often diagnosed with a delay. The aim of this article is to review the well known and less known eye abnormalities related to hypertension, and place them in the context of population based studies. Hypertension affects various parts of the eye. The originally classified hypertensive retinopathy (retinal microvascular changes) is still relevant, but new features are visible in cases of controlled hypertension. Signs of mild hypertensive retinopathy are more common than expected occurring in nearly 10-15% of the adult non-diabetic population. Hypertensive retinopathy can be an indicator of other hypertensive complications such as neurologic and cardiac complications. Microvascular changes are reversible in well controlled hypertension. Proper treatment of hypertension can reduce the development and progression of diabetic retinopathy and, thus, visual loss due to severe retinal diseases such as retinal vascular occlusion (artery and vein), retinal arteriolar emboli, macroaneurysm, ischemic optic neuropathy and age-related macular degeneration.

An ocular view of the IGF-IGFBP system

IGFs and their binding proteins have been shown to exhibit both protective and deleterious effects in ocular disease. Recent studies have characterized the expression patterns of different IGFBPs in retinal layers and within the vitreous. IGFBP-3 has roles in vascular protection stimulating proliferation, migration, and differentiation of vascular progenitor cells to sites of injury. IGFBP-3 increases pericyte ensheathment and shows anti-inflammatory effects by reducing microglia activation in diabetes. IGFBP-5 has recently been linked to mediating fibrosis in proliferative vitreoretinopathy but also reduces neovascularization. Thus, the regulatory balance between IGF and IGFBPs can have profound impact on target tissues. This review discusses recent findings of IGF and IGFBP expression in the eye with relevance to different retinopathies.