Pub Date : 2024-12-29DOI: 10.1016/j.mvr.2024.104781
Robert G. Hahn , Katerina Tlapakova , Hana Koudelova , Veronika Knoblochova , David Rehak , Vladimir Cerny , David Astapenko
Background
Excess fluid in the interstitium can adversely affect the microcirculation. We studied how gradual dilution of the blood plasma by crystalloid fluid influences microcirculatory variables and capillary filtration in 20 patients undergoing surgery.
Methods
Video recordings of the sublingual mucosal were made on four occasions during the surgery and compared with quasi-measurements of the capillary filtration rate using retrospective volume kinetic data collected over 5–10-minute periods during 262 infusion experiments with crystalloid fluid.
Results
The number of crossings (vessel density) increased up to plasma dilution of 15–20 % whereafter it decreased. The proportion of the vessels that were perfused (PPV) decreased and reached a nadir of −15 % at a dilution of 20–30 %. Changes in the number of crossings and the PPV correlated (r = 0.62, P < 0.001) but the curve was displaced so that crossings showed no change when PPV had decreased by approximately 10 %. However, the PPV of vessels with a thickness of ≤25 μm increased or remained constant in the dilution range of up to 20 %. The volume kinetic analysis showed that the capillary filtration was greater than expected from proportionality with the volume expansion up to a plasma dilution of 15 %, the greatest difference (+89 %) being for plasma dilution up to 5 %.
Conclusion
Plasma dilution of up to 15 % increased the vessel density, and the capillary filtration increased by more than suggested by the volume expansion. Dilution >15 % had a negative influence on these variables.
{"title":"Low-grade hemodilution improves the microcirculatory function in surgical patients","authors":"Robert G. Hahn , Katerina Tlapakova , Hana Koudelova , Veronika Knoblochova , David Rehak , Vladimir Cerny , David Astapenko","doi":"10.1016/j.mvr.2024.104781","DOIUrl":"10.1016/j.mvr.2024.104781","url":null,"abstract":"<div><h3>Background</h3><div>Excess fluid in the interstitium can adversely affect the microcirculation. We studied how gradual dilution of the blood plasma by crystalloid fluid influences microcirculatory variables and capillary filtration in 20 patients undergoing surgery.</div></div><div><h3>Methods</h3><div>Video recordings of the sublingual mucosal were made on four occasions during the surgery and compared with quasi-measurements of the capillary filtration rate using retrospective volume kinetic data collected over 5–10-minute periods during 262 infusion experiments with crystalloid fluid.</div></div><div><h3>Results</h3><div>The number of crossings (vessel density) increased up to plasma dilution of 15–20 % whereafter it decreased. The proportion of the vessels that were perfused (PPV) decreased and reached a nadir of −15 % at a dilution of 20–30 %. Changes in the number of crossings and the PPV correlated (<em>r</em> = 0.62, <em>P</em> < 0.001) but the curve was displaced so that crossings showed no change when PPV had decreased by approximately 10 %. However, the PPV of vessels with a thickness of ≤25 μm increased or remained constant in the dilution range of up to 20 %. The volume kinetic analysis showed that the capillary filtration was greater than expected from proportionality with the volume expansion up to a plasma dilution of 15 %, the greatest difference (+89 %) being for plasma dilution up to 5 %.</div></div><div><h3>Conclusion</h3><div>Plasma dilution of up to 15 % increased the vessel density, and the capillary filtration increased by more than suggested by the volume expansion. Dilution >15 % had a negative influence on these variables.</div></div>","PeriodicalId":18534,"journal":{"name":"Microvascular research","volume":"158 ","pages":"Article 104781"},"PeriodicalIF":2.9,"publicationDate":"2024-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142910036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Diabetes mellitus (DM) is a metabolic abnormality affecting 537 million people worldwide. Poor glycemic control, longer duration, and poor medication adherence increased the risk of DM complications. Comprehensive evidence on the pooled prevalence of microvascular complications in DM patients in Ethiopia is not available. Furthermore, individual study findings for the prevalence of microvascular complications in DM patients, and associated factors were not consistent.
Objective
This systemic review and meta-analysis aimed to assess the pooled prevalence of microvascular complications in DM patients, and its associated risk factors in Ethiopia.
Methods
Systematic search on Scopus, PubMed, Science Direct electronic database, Google Scholar search engine, and library registration was used to identify relevant studies following reviews and meta-analysis guidelines. Microsoft Excel spreadsheets were used to extract data, and Extracted data was analyzed using STATA software version 17.0. A Sensitivity analysis was conducted to assess the role of each study in the final result and the presence of publication bias was assessed by Egger's test. Heterogeneity across studies was checked by Cochran's Q statistic and I2 statistics and significant heterogeneity was assessed using subgroup analysis.
Results
The pooled prevalence of microvascular complications in DM patients was 32.89 % (95 % CI: 28.17–37.60). In addition, the pooled prevalence of retinopathy, neuropathy, and nephropathy in DM patients was 17.16 % (95 % CI: 12–22 %), 10.49 % (95 % CI: 8–13 %) and 11.52 % (95 % CI: 9–15 %) respectively. Age >60 years old (AOR = 1.08 (95%CI = 1.02–1.15), longer duration of DM (AOR = 1.57 (95 % CI = 1.31–1.84), poor glycemic control (AOR = 2.21 (95 % CI = 1.52–2.91), poor adherence to diabetic medications (AOR = 3.61 (95 % CI = 1.83–5.38) and presence of hypertension (AOR = 2.26 (95 % CI = 1.73–2.80) ware associated risk factors for microvascular complications in DM patients.
Concussion
Around one-third of DM patients had one or more microvascular complications. Patients with advanced age, longer duration of DM, poor glycemic control, poor medication adherence, and comorbidity like hypertension should be targeted to tackle the occurrence and severity of microvascular complications in DM patients.
Protocol registration
The review protocol was developed and was registered with PROSPERO registration number (CRD42023486459).
{"title":"Prevalence of microvascular complications and associated factors among diabetes mellitus patients in Ethiopia: Systematic review and meta-analysis","authors":"Getinet Kumie , Marye Nigatie , Abebaw Alamrew , Solomon Gedifie , Woldeteklehaymanot Kassahun , Abdu Jemal , Chalie Mulugeta , Sisay Ayana , Mulat Ayele , Eyob Shitie , Belaynesh Gtsadik , Wagaw Abebe , Agenagnew Ashagre , Tadesse Misganaw , Zelalem Dejazmach , Assefa Sisay , Zelalem Asmare , Muluken Gashaw , Ermias Getachew , Yalewayker Gashaw , Melesse Abate Reta","doi":"10.1016/j.mvr.2024.104779","DOIUrl":"10.1016/j.mvr.2024.104779","url":null,"abstract":"<div><h3>Background</h3><div>Diabetes mellitus (DM) is a metabolic abnormality affecting 537 million people worldwide. Poor glycemic control, longer duration, and poor medication adherence increased the risk of DM complications. Comprehensive evidence on the pooled prevalence of microvascular complications in DM patients in Ethiopia is not available. Furthermore, individual study findings for the prevalence of microvascular complications in DM patients, and associated factors were not consistent.</div></div><div><h3>Objective</h3><div>This systemic review and meta-analysis aimed to assess the pooled prevalence of microvascular complications in DM patients, and its associated risk factors in Ethiopia.</div></div><div><h3>Methods</h3><div>Systematic search on Scopus, PubMed, Science Direct electronic database, Google Scholar search engine, and library registration was used to identify relevant studies following reviews and meta-analysis guidelines. Microsoft Excel spreadsheets were used to extract data, and Extracted data was analyzed using STATA software version 17.0. A Sensitivity analysis was conducted to assess the role of each study in the final result and the presence of publication bias was assessed by Egger's test. Heterogeneity across studies was checked by Cochran's Q statistic and I2 statistics and significant heterogeneity was assessed using subgroup analysis.</div></div><div><h3>Results</h3><div>The pooled prevalence of microvascular complications in DM patients was 32.89 % (95 % CI: 28.17–37.60). In addition, the pooled prevalence of retinopathy, neuropathy, and nephropathy in DM patients was 17.16 % (95 % CI: 12–22 %), 10.49 % (95 % CI: 8–13 %) and 11.52 % (95 % CI: 9–15 %) respectively. Age >60 years old (AOR = 1.08 (95%CI = 1.02–1.15), longer duration of DM (AOR = 1.57 (95 % CI = 1.31–1.84), poor glycemic control (AOR = 2.21 (95 % CI = 1.52–2.91), poor adherence to diabetic medications (AOR = 3.61 (95 % CI = 1.83–5.38) and presence of hypertension (AOR = 2.26 (95 % CI = 1.73–2.80) ware associated risk factors for microvascular complications in DM patients.</div></div><div><h3>Concussion</h3><div>Around one-third of DM patients had one or more microvascular complications. Patients with advanced age, longer duration of DM, poor glycemic control, poor medication adherence, and comorbidity like hypertension should be targeted to tackle the occurrence and severity of microvascular complications in DM patients.</div></div><div><h3>Protocol registration</h3><div>The review protocol was developed and was registered with PROSPERO registration number (CRD42023486459).</div></div>","PeriodicalId":18534,"journal":{"name":"Microvascular research","volume":"158 ","pages":"Article 104779"},"PeriodicalIF":2.9,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142896112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-19DOI: 10.1016/j.mvr.2024.104780
Natallia Laptseva , Konstantinos Bitos , Valentina A. Rossi , Delia Nebunu , Thomas Haider , Matthias P. Nägele , Carina Mihai , Oliver Distler , Frank Ruschitzka , Isabella Sudano , Andreas J. Flammer
Background and aims
Systemic sclerosis (SSc) is a systemic autoimmune disease, characterized by widespread microvasculopathy and fibrosis. Vascular and endothelial cell changes appear to precede other features of SSc. Retinal vascular analysis is a new, easy-to-use tool for the assessment of retinal microvascular function. The primary aim of this study was to investigate whether retinal microcirculation is affected in patients with SSc compared to healthy controls.
Methods
Microvascular function was assessed non-invasively measuring flicker-light induced vasodilation of retinal arterioles (FIDart%). In addition, FID of retinal venules (FIDven%), central retinal arteriolar and venular equivalents (CRAE and CRVE), and measurements of flow-mediated vasodilation (FMD) of the brachial artery, pulse wave velocity (PWV) and pulse wave analysis were obtained. Patients with SSc were prospectively enrolled in the study (n = 40, mean age 56 ± 11 years, females 73 %) and compared with age- and sex-matched healthy controls (HC, n = 40; mean age 59 ± 15 years, females 73 %).
Results
Patients with SSc showed significant impairment of retinal microvascular function compared to age- and gender-matched HC (FIDart%: 2.23 ± 2.0 % vs. 3.1 ± 1.9 %, respectively, p = 0.04). FMD and PWV were not significantly different between the groups. Impaired retinal microvascular function was associated with SSc disease duration.
Conclusion
Our study shows a significant impairment of retinal microvascular function in patients with SSc. Because this association seems to be independent of CV risk and dependent on disease duration, retinal vessel analysis may have the potential to serve as a tool for risk assessment and prognosis.
{"title":"Retinal microvascular dysfunction in systemic sclerosis","authors":"Natallia Laptseva , Konstantinos Bitos , Valentina A. Rossi , Delia Nebunu , Thomas Haider , Matthias P. Nägele , Carina Mihai , Oliver Distler , Frank Ruschitzka , Isabella Sudano , Andreas J. Flammer","doi":"10.1016/j.mvr.2024.104780","DOIUrl":"10.1016/j.mvr.2024.104780","url":null,"abstract":"<div><h3>Background and aims</h3><div>Systemic sclerosis (SSc) is a systemic autoimmune disease, characterized by widespread microvasculopathy and fibrosis. Vascular and endothelial cell changes appear to precede other features of SSc. Retinal vascular analysis is a new, easy-to-use tool for the assessment of retinal microvascular function. The primary aim of this study was to investigate whether retinal microcirculation is affected in patients with SSc compared to healthy controls.</div></div><div><h3>Methods</h3><div>Microvascular function was assessed non-invasively measuring flicker-light induced vasodilation of retinal arterioles (FIDart%). In addition, FID of retinal venules (FIDven%), central retinal arteriolar and venular equivalents (CRAE and CRVE), and measurements of flow-mediated vasodilation (FMD) of the brachial artery, pulse wave velocity (PWV) and pulse wave analysis were obtained. Patients with SSc were prospectively enrolled in the study (<em>n</em> = 40, mean age 56 ± 11 years, females 73 %) and compared with age- and sex-matched healthy controls (HC, n = 40; mean age 59 ± 15 years, females 73 %).</div></div><div><h3>Results</h3><div>Patients with SSc showed significant impairment of retinal microvascular function compared to age- and gender-matched HC (FIDart%: 2.23 ± 2.0 % vs. 3.1 ± 1.9 %, respectively, <em>p</em> = 0.04). FMD and PWV were not significantly different between the groups. Impaired retinal microvascular function was associated with SSc disease duration.</div></div><div><h3>Conclusion</h3><div>Our study shows a significant impairment of retinal microvascular function in patients with SSc. Because this association seems to be independent of CV risk and dependent on disease duration, retinal vessel analysis may have the potential to serve as a tool for risk assessment and prognosis.</div></div>","PeriodicalId":18534,"journal":{"name":"Microvascular research","volume":"158 ","pages":"Article 104780"},"PeriodicalIF":2.9,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142872547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Background: Blood flow restriction caused by peripheral arterial disease (PAD) is reflected in reduced walking capacity. The peripheral mechanisms that may affect the walking capacity of individuals with PAD are not yet fully understood. This study aimed to 1) compare tissue oxygenation and muscle metabolism of individuals with PAD with different walking capacities and 2) evaluate which variables have the greatest potential to explain the variability in distance walked between performance levels. Methods: The sample composed of adults diagnosed with PAD underwent evaluation of microvascular function in the gastrocnemius muscle through Near-Infrared Spectroscopy (NIRS) at two time points: (1) during the arterial occlusion maneuver; (2) on a treadmill test with constant speed and inclination (3.2 km/h, 10 %). The following NIRS parameters were selected: (1) percentage of peripheral tissue oxygen saturation (StO2); (2) StO2 delta; (3) reoxygenation rate; (4) time to reach lowest StO2; (5) ischemia resistance time; (6) StO2 in reactive hyperemia. Participants were divided into tertiles (T1, T2, and T3) according to the walking distance in the treadmill test. One-way analysis of variance (ANOVA) was used for comparisons between tertiles and multiple linear regression was used for association analyses. Results: There were no significant differences between tertiles in baseline values or delta StO2. The reoxygenation rate and StO2 in hyperemia of the occlusion maneuver, as well as the time to reach the lowest StO2 and the ischemia resistance time in the treadmill test, were significantly higher in T3 than in T1 and T2 (p < 0.05). Linear regression demonstrated that the ischemia resistance time is the variable that appears to have the greatest influence on the distance walked (adjusted R2 = 0.83). Conclusion: Better walking performance was associated with better dynamic response capacity to ischemia. Factors such as microvascular, endothelial, and muscular dysfunction appear to be decisive in reducing the walking capacity of individuals with PAD.
背景：外周动脉疾病（PAD）导致的血流限制反映在行走能力的降低上。可能影响 PAD 患者行走能力的外周机制尚不完全清楚。本研究旨在：1）比较具有不同步行能力的 PAD 患者的组织氧合和肌肉代谢情况；2）评估哪些变量最有可能解释不同能力水平的步行距离差异：由确诊为 PAD 的成年人组成的样本在两个时间点通过近红外光谱（NIRS）对腓肠肌的微血管功能进行了评估：（1）动脉闭塞操作期间；（2）恒定速度和倾斜度的跑步机测试（3.2 km/h，10%）。选择的近红外光谱参数如下：（1）外周组织氧饱和度（StO2）百分比；（2）StO2 delta；（3）复氧速率；（4）达到最低 StO2 的时间；（5）缺血抵抗时间；（6）反应性充血时的 StO2。根据跑步机测试中的步行距离将参与者分为三等分（T1、T2 和 T3）。采用单因素方差分析（ANOVA）对不同分层进行比较，采用多元线性回归进行关联分析：结果：各分层之间的基线值或δ StO2 均无明显差异。结论：T3 组的再氧速率和闭塞动作高充血状态下的 StO2，以及跑步机测试中达到最低 StO2 的时间和缺血抵抗时间均显著高于 T1 和 T2 组（P 2 = 0.83）：结论：更好的步行表现与更好的缺血动态反应能力有关。微血管、内皮和肌肉功能障碍等因素似乎是降低 PAD 患者行走能力的决定性因素。
{"title":"Muscle tissue oxygenation in individuals with peripheral arterial disease of different walking abilities: An exploratory study","authors":"Gisela Maria Pontes Przybysz , Patrícia Paulino Geisel , Isabella de Oliveira Nascimento , Débora Pantuso Monteiro , Rafaela Pedrosa , Danielle Aparecida Gomes Pereira","doi":"10.1016/j.mvr.2024.104778","DOIUrl":"10.1016/j.mvr.2024.104778","url":null,"abstract":"<div><div>Background: Blood flow restriction caused by peripheral arterial disease (PAD) is reflected in reduced walking capacity. The peripheral mechanisms that may affect the walking capacity of individuals with PAD are not yet fully understood. This study aimed to 1) compare tissue oxygenation and muscle metabolism of individuals with PAD with different walking capacities and 2) evaluate which variables have the greatest potential to explain the variability in distance walked between performance levels. Methods: The sample composed of adults diagnosed with PAD underwent evaluation of microvascular function in the gastrocnemius muscle through Near-Infrared Spectroscopy (NIRS) at two time points: (1) during the arterial occlusion maneuver; (2) on a treadmill test with constant speed and inclination (3.2 km/h, 10 %). The following NIRS parameters were selected: (1) percentage of peripheral tissue oxygen saturation (StO<sub>2</sub>); (2) StO<sub>2</sub> delta; (3) reoxygenation rate; (4) time to reach lowest StO<sub>2</sub>; (5) ischemia resistance time; (6) StO<sub>2</sub> in reactive hyperemia. Participants were divided into tertiles (T1, T2, and T3) according to the walking distance in the treadmill test. One-way analysis of variance (ANOVA) was used for comparisons between tertiles and multiple linear regression was used for association analyses. Results: There were no significant differences between tertiles in baseline values or delta StO<sub>2</sub>. The reoxygenation rate and StO<sub>2</sub> in hyperemia of the occlusion maneuver, as well as the time to reach the lowest StO<sub>2</sub> and the ischemia resistance time in the treadmill test, were significantly higher in T3 than in T1 and T2 (<em>p</em> < 0.05). Linear regression demonstrated that the ischemia resistance time is the variable that appears to have the greatest influence on the distance walked (adjusted R<sup>2</sup> = 0.83). Conclusion: Better walking performance was associated with better dynamic response capacity to ischemia. Factors such as microvascular, endothelial, and muscular dysfunction appear to be decisive in reducing the walking capacity of individuals with PAD.</div></div>","PeriodicalId":18534,"journal":{"name":"Microvascular research","volume":"158 ","pages":"Article 104778"},"PeriodicalIF":2.9,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142818609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-28DOI: 10.1016/j.mvr.2024.104777
Luyun Zhang , Shaoya Rong , Hui Dong
Although the mouse mesenteric artery is widely used as a model of resistance vessels, it is unknown which order branch is the best representative and if there is a heterogeneity of vascular activity in different orders. We systematically compared the vasorelaxation between the mouse mesenteric artery's first- and second-order branches. The first- and second-order branches of the mesenteric artery (lumen diameter of >300 μm and 179.9 ± 11.1 μm, respectively) were taken from the location close to their branching points in wide-type (WT) and TRPV4−/− (KO) mice. Vasorelaxation of the mesenteric artery was measured using a Danish DMT520A microvascular system. Acetylcholine (ACh) induced much greater vasorelaxation via TRPV4 channels/endothelium-dependent hyperpolarization (EDH/H2S) in the second-order branch. The store-operated Ca2+ entry (SOCE) mediated much greater vasorelaxation via EDH in the second-order branch than that via NO in the first-order branch. However, capsaicin-induced vasorelaxation was much greater via TRPV1/NO and TRPV1/CGRP in the first-order branch than TRPV4/EDH only in the second-order branch. Moreover, sex differences in ACh-induced vasorelaxation were obviously in the first-order branch but marginally in the second-order branch. Mechanistically, the myoendothelial gap junction (MEGJ) is involved in ACh-induced vasorelaxation in the second-order branch but not in the first-order branch. However, endothelial IKCa and SKCa functions and endothelium-independent vasorelaxation were similar for both first- and second-order branches. TRPV1/NO/CGRP mediates endothelium-dependent vasorelaxation in the first-order branch as the best representative of conduit vessels, but TRPV4/EDH/H2S mediates endothelium-dependent vasorelaxation in the second-order branch as the best representative of resistance vessels in mice.
{"title":"Functional heterogeneity of endothelium-dependent vasorelaxation in different order branches of mesenteric artery in female/male mice","authors":"Luyun Zhang , Shaoya Rong , Hui Dong","doi":"10.1016/j.mvr.2024.104777","DOIUrl":"10.1016/j.mvr.2024.104777","url":null,"abstract":"<div><div>Although the mouse mesenteric artery is widely used as a model of resistance vessels, it is unknown which order branch is the best representative and if there is a heterogeneity of vascular activity in different orders. We systematically compared the vasorelaxation between the mouse mesenteric artery's first- and second-order branches. The first- and second-order branches of the mesenteric artery (lumen diameter of >300 μm and 179.9 ± 11.1 μm, respectively) were taken from the location close to their branching points in wide-type (WT) and TRPV4<sup>−/−</sup> (KO) mice. Vasorelaxation of the mesenteric artery was measured using a Danish DMT520A microvascular system. Acetylcholine (ACh) induced much greater vasorelaxation via TRPV4 channels/endothelium-dependent hyperpolarization (EDH/H<sub>2</sub>S) in the second-order branch. The store-operated Ca<sup>2+</sup> entry (SOCE) mediated much greater vasorelaxation via EDH in the second-order branch than that via NO in the first-order branch. However, capsaicin-induced vasorelaxation was much greater via TRPV1/NO and TRPV1/CGRP in the first-order branch than TRPV4/EDH only in the second-order branch. Moreover, sex differences in ACh-induced vasorelaxation were obviously in the first-order branch but marginally in the second-order branch. Mechanistically, the myoendothelial gap junction (MEGJ) is involved in ACh-induced vasorelaxation in the second-order branch but not in the first-order branch. However, endothelial IK<sub>Ca</sub> and SK<sub>Ca</sub> functions and endothelium-independent vasorelaxation were similar for both first- and second-order branches. TRPV1/NO/CGRP mediates endothelium-dependent vasorelaxation in the first-order branch as the best representative of conduit vessels, but TRPV4/EDH/H<sub>2</sub>S mediates endothelium-dependent vasorelaxation in the second-order branch as the best representative of resistance vessels in mice.</div></div>","PeriodicalId":18534,"journal":{"name":"Microvascular research","volume":"158 ","pages":"Article 104777"},"PeriodicalIF":2.9,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142755241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-23DOI: 10.1016/j.mvr.2024.104772
Nik Nor Izah Nik Ibrahim , Aida Hanum Ghulam Rasool , Razlina Abdul Rahman , Maryam Azlan , Aniza Abd Aziz
Background
Pulse wave analysis (PWA) assesses endothelial dependent vasodilation (EDV) via the change in augmentation index (AIx) and has been used as a tool to assess endothelial function. However, its effectiveness in assessing the response to lipid lowering treatment has not been evaluated. The study aimed to describe and correlate the change in EDV following lipid lowering intervention in patients with hypercholesterolemia.
Methods
48 newly diagnosed patients with hypercholesterolemia underwent 6 months intervention with statin and/or therapeutic lifestyle changes (TLC) in clinical setting. Lipid profile measurement and endothelial function assessment using PWA were performed pre- and post-intervention.
Results
Significant reductions in low density lipoprotein cholesterol (LDL-C), non-high density lipoprotein cholesterol (non-HDL-C) and total cholesterol (TC) with corresponding significant improvement in EDV (2.94 ± 3.69 % to 7.50 ± 3.79 %, p < 0.001) were observed following intervention. Sub-analyses revealed greater LDL-C reductions and EDV improvements in the statin group compared to TLC. There was a significant inverse correlation between the change in EDV and the change in LDL-C after intervention (r = −0.298, p = 0.040).
Conclusion
Endothelial function assessed by PWA showed a parallel change with lipid profile pattern following lipid lowering intervention. The simple and non-invasive method may provide a potential tool for evaluating endothelial function and treatment outcomes in patients with hypercholesterolemia.
{"title":"Pulse wave analysis as a tool to assess endothelial function following lipid lowering intervention in hypercholesterolemia","authors":"Nik Nor Izah Nik Ibrahim , Aida Hanum Ghulam Rasool , Razlina Abdul Rahman , Maryam Azlan , Aniza Abd Aziz","doi":"10.1016/j.mvr.2024.104772","DOIUrl":"10.1016/j.mvr.2024.104772","url":null,"abstract":"<div><h3>Background</h3><div>Pulse wave analysis (PWA) assesses endothelial dependent vasodilation (EDV) via the change in augmentation index (AIx) and has been used as a tool to assess endothelial function. However, its effectiveness in assessing the response to lipid lowering treatment has not been evaluated. The study aimed to describe and correlate the change in EDV following lipid lowering intervention in patients with hypercholesterolemia.</div></div><div><h3>Methods</h3><div>48 newly diagnosed patients with hypercholesterolemia underwent 6 months intervention with statin and/or therapeutic lifestyle changes (TLC) in clinical setting. Lipid profile measurement and endothelial function assessment using PWA were performed pre- and post-intervention.</div></div><div><h3>Results</h3><div>Significant reductions in low density lipoprotein cholesterol (LDL-C), non-high density lipoprotein cholesterol (non-HDL-C) and total cholesterol (TC) with corresponding significant improvement in EDV (2.94 ± 3.69 % to 7.50 ± 3.79 %, <em>p</em> < 0.001) were observed following intervention. Sub-analyses revealed greater LDL-C reductions and EDV improvements in the statin group compared to TLC. There was a significant inverse correlation between the change in EDV and the change in LDL-C after intervention (<em>r</em> = −0.298, <em>p</em> = 0.040).</div></div><div><h3>Conclusion</h3><div>Endothelial function assessed by PWA showed a parallel change with lipid profile pattern following lipid lowering intervention. The simple and non-invasive method may provide a potential tool for evaluating endothelial function and treatment outcomes in patients with hypercholesterolemia.</div></div>","PeriodicalId":18534,"journal":{"name":"Microvascular research","volume":"158 ","pages":"Article 104772"},"PeriodicalIF":2.9,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142716771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-19DOI: 10.1016/j.mvr.2024.104763
Rui Tao , Zhenyu Wei , Xiaoxia Chen , Qian Wang , Xiuduo Liu , Qing Lu , Jie Zhao , Hui Zhou
Aim
To reveal alterations in retinal structure, vessels, and function, and their association with cognitive function and neuroimaging in white matter hyperintensities (WMH).
Methods
This study enlisted WMH and age-matched healthy controls (HC). All participants underwent six different tests: magnetic resonance imaging (MRI) of the brain, the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA), fundus photography, optical coherence tomography (OCT), and visual field testing. Visual field can reflect the function of optic nerve and retina. The peripapillary retinal nerve fiber layer (p-RNFL) was analyzed using OCT. Image J software was employed to measure retinal vascular caliber in fundus photographs and to compute the central retinal artery equivalent (CRAE), central retinal venous equivalent (CRVE) and arteriole-to-venule ratio (AVR).
Results
A total of 90 WMH patients and 93 HC participants. In comparison with the HC, the WMH group exhibited reduced cognitive function scores (MoCA: P < 0.001; MMSE: P < 0.001), narrower retinal arteries (P < 0.001), smaller AVR (P < 0.001) and thinner p-RNFL thickness (total: P = 0.026; temporal: P = 0.006). About visual field, both univariate and multivariate analysis showed that mean sensitivity decreased, and mean defect increased in WMH group (P < 0.05). Additionally, correlation analysis indicated a positive correlation between CRAE and AVR with MMSE and MoCA score (r = 0.424–0.57, P < 0.001) and a negative correlation with Fazekas score (CRAE: r = −0.515, P < 0.001; AVR: r = −0.554, P < 0.001), and p-RNFL was negatively correlated with Fazekas score (total p-RNFL: r = −0.192, P = 0.009; temporal p-RNFL: r = −0.217, P = 0.003). Notably, no significant correlation was found between cognitive function and p-RNFL.
Conclusion
WMH group exhibit narrower retinal arteries, smaller arteriole-to-venule ratio, damaged p-RNFL and visual function. These alterations in retinal vessels are associate with both neuroimaging and cognitive function. Our results suggest that retinal imaging could serve as a valuable instrument for evaluating WMH and provides some new approaches to study the characteristic markers of WMH.
目的：揭示白质高密度症（WMH）患者视网膜结构、血管和功能的改变及其与认知功能和神经影像学的关联：本研究招募了 WMH 和年龄匹配的健康对照组（HC）。所有参与者都接受了六项不同的测试：脑部磁共振成像（MRI）、迷你精神状态检查（MMSE）、蒙特利尔认知评估（MoCA）、眼底照相、光学相干断层扫描（OCT）和视野测试。视野可反映视神经和视网膜的功能。光学相干断层扫描分析了视网膜周围神经纤维层（p-RNFL）。使用 Image J 软件测量眼底照片中的视网膜血管口径，并计算视网膜中央动脉等值（CRAE）、视网膜中央静脉等值（CRVE）和动静脉比（AVR）：共有90名WMH患者和93名HC参与者。与 HC 相比，WMH 组患者的认知功能评分降低（MoCA：P 结论：WMH 组患者的视网膜变窄，而 HC 组患者的视网膜变窄：WMH 组表现出视网膜动脉变窄、动脉血管与小动脉之比变小、p-RNFL 和视觉功能受损。视网膜血管的这些改变与神经影像学和认知功能都有关联。我们的研究结果表明，视网膜成像可作为评估 WMH 的重要工具，并为研究 WMH 的特征标记提供了一些新方法。
{"title":"Retinal vascular alterations are associated with cognitive function and neuroimaging in white matter hyperintensities","authors":"Rui Tao , Zhenyu Wei , Xiaoxia Chen , Qian Wang , Xiuduo Liu , Qing Lu , Jie Zhao , Hui Zhou","doi":"10.1016/j.mvr.2024.104763","DOIUrl":"10.1016/j.mvr.2024.104763","url":null,"abstract":"<div><h3>Aim</h3><div>To reveal alterations in retinal structure, vessels, and function, and their association with cognitive function and neuroimaging in white matter hyperintensities (WMH).</div></div><div><h3>Methods</h3><div>This study enlisted WMH and age-matched healthy controls (HC). All participants underwent six different tests: magnetic resonance imaging (MRI) of the brain, the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA), fundus photography, optical coherence tomography (OCT), and visual field testing. Visual field can reflect the function of optic nerve and retina. The peripapillary retinal nerve fiber layer (p-RNFL) was analyzed using OCT. Image J software was employed to measure retinal vascular caliber in fundus photographs and to compute the central retinal artery equivalent (CRAE), central retinal venous equivalent (CRVE) and arteriole-to-venule ratio (AVR).</div></div><div><h3>Results</h3><div>A total of 90 WMH patients and 93 HC participants. In comparison with the HC, the WMH group exhibited reduced cognitive function scores (MoCA: P < 0.001; MMSE: P < 0.001), narrower retinal arteries (P < 0.001), smaller AVR (P < 0.001) and thinner p-RNFL thickness (total: P = 0.026; temporal: P = 0.006). About visual field, both univariate and multivariate analysis showed that mean sensitivity decreased, and mean defect increased in WMH group (P < 0.05). Additionally, correlation analysis indicated a positive correlation between CRAE and AVR with MMSE and MoCA score (r = 0.424–0.57, P < 0.001) and a negative correlation with Fazekas score (CRAE: r = −0.515, P < 0.001; AVR: r = −0.554, P < 0.001), and p-RNFL was negatively correlated with Fazekas score (total p-RNFL: r = −0.192, P = 0.009; temporal p-RNFL: r = −0.217, P = 0.003). Notably, no significant correlation was found between cognitive function and p-RNFL.</div></div><div><h3>Conclusion</h3><div>WMH group exhibit narrower retinal arteries, smaller arteriole-to-venule ratio, damaged p-RNFL and visual function. These alterations in retinal vessels are associate with both neuroimaging and cognitive function. Our results suggest that retinal imaging could serve as a valuable instrument for evaluating WMH and provides some new approaches to study the characteristic markers of WMH.</div></div>","PeriodicalId":18534,"journal":{"name":"Microvascular research","volume":"158 ","pages":"Article 104763"},"PeriodicalIF":2.9,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142681112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-19DOI: 10.1016/j.mvr.2024.104764
Akiko Kawakami , Hiroaki Sato , Yosuke Nakadate , Patricia Roque , Arkady Khoutorsky , Takashi Matsukawa , Thomas Schricker
Introduction
l-glutamine has been shown to have cardioprotective effects in models of ischemia-reperfusion injury. Its potential cardioprotective effects when given before and during early reperfusion, however, have not been studied.
Methods
This study hypothesized that l-glutamine administered before and after myocardial ischemia provides better cardioprotection than when administered after ischemia only. Eighteen male rat hearts were exposed to 15 min of ischemia using the Langendorff system and randomly assigned to three groups of six each. Group one received Krebs-Henseleit (KH) buffer over 20 min before ischemia and during 20 min of reperfusion (Control), group two received KH buffer containing 2.5 mmol･L−1 glutamine during reperfusion (Post-Gln) and group three was given KH buffer containing glutamine before and after the ischemic insult (Pre + Post-Gln). Indicators of hemodynamics such as maximum left ventricular derivative of pressure development (LV dP/dt max) were recorded at 5, 10, 15 and 20 min post-reperfusion. Myocardial levels of O-linked β-N-acetylglucosamine (O-GlcNAc) and heat shock protein 70 (HSP70) were measured by Western blotting technique after 20 min of reperfusion.
Results
The LV dp/dt max in the Pre + Post-Gln group was significantly elevated as compared to the Post-Gln group after 10 min of reperfusion and was significantly higher than in the control group at all-time points. Myocardial expression of O-GlcNAc was increased in the Pre + Post-Gln group (P < 0.01 vs. control) without showing any differences in HSP70.
Conclusion
In this model of stunned myocardium, pre- and post-ischemic administration of l-glutamine improved cardiac function indicating cardioprotective effects, possibly mediated by O-GlcNAc.
{"title":"Cardioprotective effects of l-glutamine in an ischemic rat heart model","authors":"Akiko Kawakami , Hiroaki Sato , Yosuke Nakadate , Patricia Roque , Arkady Khoutorsky , Takashi Matsukawa , Thomas Schricker","doi":"10.1016/j.mvr.2024.104764","DOIUrl":"10.1016/j.mvr.2024.104764","url":null,"abstract":"<div><h3>Introduction</h3><div><span>l</span>-glutamine has been shown to have cardioprotective effects in models of ischemia-reperfusion injury. Its potential cardioprotective effects when given before and during early reperfusion, however, have not been studied.</div></div><div><h3>Methods</h3><div>This study hypothesized that <span>l</span>-glutamine administered before and after myocardial ischemia provides better cardioprotection than when administered after ischemia only. Eighteen male rat hearts were exposed to 15 min of ischemia using the Langendorff system and randomly assigned to three groups of six each. Group one received Krebs-Henseleit (KH) buffer over 20 min before ischemia and during 20 min of reperfusion (Control), group two received KH buffer containing 2.5 mmol･L<sup>−1</sup> glutamine during reperfusion (Post-Gln) and group three was given KH buffer containing glutamine before and after the ischemic insult (Pre + Post-Gln). Indicators of hemodynamics such as maximum left ventricular derivative of pressure development (LV dP/dt max) were recorded at 5, 10, 15 and 20 min post-reperfusion. Myocardial levels of O-linked β-<em>N</em>-acetylglucosamine (O-GlcNAc) and heat shock protein 70 (HSP70) were measured by Western blotting technique after 20 min of reperfusion.</div></div><div><h3>Results</h3><div>The LV dp/dt max in the Pre + Post-Gln group was significantly elevated as compared to the Post-Gln group after 10 min of reperfusion and was significantly higher than in the control group at all-time points. Myocardial expression of O-GlcNAc was increased in the Pre + Post-Gln group (<em>P</em> < 0.01 vs. control) without showing any differences in HSP70.</div></div><div><h3>Conclusion</h3><div>In this model of stunned myocardium, pre- and post-ischemic administration of <span>l</span>-glutamine improved cardiac function indicating cardioprotective effects, possibly mediated by O-GlcNAc.</div></div>","PeriodicalId":18534,"journal":{"name":"Microvascular research","volume":"158 ","pages":"Article 104764"},"PeriodicalIF":2.9,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142687058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-19DOI: 10.1016/j.mvr.2024.104765
Antonios Stathoulopoulos , Carola S. König , Sudarshan Ramachandran , Stavroula Balabani
The impact of therapeutic interventions on red blood cell (RBC) deformability and microscale transport is investigated, using statins as an exemplar. Human RBCs were treated in vitro with two commonly prescribed statins, atorvastatin and rosuvastatin, at clinically relevant concentrations. Changes in RBC deformability were quantified using a microfluidic-based ektacytometer and expressed in terms of the elongation index. Dilute suspensions of the statin-treated RBCs were then perfused through a microfluidic pillar array, at a constant flow rate and negligible inertia, and imaged. Particle Tracking Velocimetry (PTV) was applied to track RBCs, identify preferential paths and estimate their velocities, whereas image processing was used to estimate cell dynamics, perfusion metrics and distributions. The findings were compared against those of healthy, untreated cells. Statins enhanced RBC deformability in agreement with literature. The extent of enhancement was found to be statin-dependent. The softer statin-treated cells were found to flow in straight, less tortuous paths, spend more time inside the pillar array and exhibit lower velocities compared to healthy RBCs, attributed to their enhanced deformation and longer shape recovery time upon impact with the array posts. The in vitro microfluidic approach demonstrated here may serve as a monitoring tool to personalise and maximise the outcome of a therapeutic treatment.
{"title":"Statin-treated RBC dynamics in a microfluidic porous-like network","authors":"Antonios Stathoulopoulos , Carola S. König , Sudarshan Ramachandran , Stavroula Balabani","doi":"10.1016/j.mvr.2024.104765","DOIUrl":"10.1016/j.mvr.2024.104765","url":null,"abstract":"<div><div>The impact of therapeutic interventions on red blood cell (RBC) deformability and microscale transport is investigated, using statins as an exemplar. Human RBCs were treated <em>in vitro</em> with two commonly prescribed statins, atorvastatin and rosuvastatin, at clinically relevant concentrations. Changes in RBC deformability were quantified using a microfluidic-based ektacytometer and expressed in terms of the elongation index. Dilute suspensions of the statin-treated RBCs were then perfused through a microfluidic pillar array, at a constant flow rate and negligible inertia, and imaged. Particle Tracking Velocimetry (PTV) was applied to track RBCs, identify preferential paths and estimate their velocities, whereas image processing was used to estimate cell dynamics, perfusion metrics and distributions. The findings were compared against those of healthy, untreated cells. Statins enhanced RBC deformability in agreement with literature. The extent of enhancement was found to be statin-dependent. The softer statin-treated cells were found to flow in straight, less tortuous paths, spend more time inside the pillar array and exhibit lower velocities compared to healthy RBCs, attributed to their enhanced deformation and longer shape recovery time upon impact with the array posts. The <em>in vitro</em> microfluidic approach demonstrated here may serve as a monitoring tool to personalise and maximise the outcome of a therapeutic treatment.</div></div>","PeriodicalId":18534,"journal":{"name":"Microvascular research","volume":"158 ","pages":"Article 104765"},"PeriodicalIF":2.9,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142687076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study aimed to explore retinal changes in Bietti crystalline dystrophy (BCD) patients, including retinal metabolism, blood flow, vascular remodeling, and pupillary light reflex (PLR) abnormalities.
Methods
This cross-sectional study included 120 eyes from BCD patients and 120 eyes from healthy controls, utilizing a multimodal imaging system (MEFIAS 3200, SYSEYE, Chongqing, China) to evaluate retinal oxygenation, blood flow, vascular structure, and PLR. Measurements included oxygen saturation, blood flow velocity, vessel diameters, and pulsatility metrics. PLR parameters were assessed under specific light stimuli.
Results
BCD patients demonstrated significantly higher retinal oxygen saturation and content, but lower oxygen utilization and metabolism compared to controls, with more pronounced declines in those over 40 years old. Vascular parameters revealed smaller external diameters and larger lumen diameters, indicating vascular remodeling. Retinal blood flow was lower, while the resistivity index was higher in BCD patients. Additionally, PLR abnormalities were noted, including reduced constriction amplitude, pupil constriction ratio, constriction duration, and maximum constriction velocity, along with prolonged latency were observed in BCD patients.
Conclusion
BCD patients had significant retinal and vascular changes, along with PLR impairments, especially in patients over 40. More targeted interventions should be focused in future research.
{"title":"A multimodal imaging approach to investigate retinal oxygen and vascular dynamics, and neural dysfunction in bietti crystalline dystrophy","authors":"Shiyi Yin , Jinyuan Wang , Jingyuan Zhu , Ximeng Feng , Haihan Zhang , Haowen Li , Jingying Xiu , Chuanqing Zhou , Qiushi Ren , Wenbin Wei","doi":"10.1016/j.mvr.2024.104762","DOIUrl":"10.1016/j.mvr.2024.104762","url":null,"abstract":"<div><h3>Background</h3><div>This study aimed to explore retinal changes in Bietti crystalline dystrophy (BCD) patients, including retinal metabolism, blood flow, vascular remodeling, and pupillary light reflex (PLR) abnormalities.</div></div><div><h3>Methods</h3><div>This cross-sectional study included 120 eyes from BCD patients and 120 eyes from healthy controls, utilizing a multimodal imaging system (MEFIAS 3200, SYSEYE, Chongqing, China) to evaluate retinal oxygenation, blood flow, vascular structure, and PLR. Measurements included oxygen saturation, blood flow velocity, vessel diameters, and pulsatility metrics. PLR parameters were assessed under specific light stimuli.</div></div><div><h3>Results</h3><div>BCD patients demonstrated significantly higher retinal oxygen saturation and content, but lower oxygen utilization and metabolism compared to controls, with more pronounced declines in those over 40 years old. Vascular parameters revealed smaller external diameters and larger lumen diameters, indicating vascular remodeling. Retinal blood flow was lower, while the resistivity index was higher in BCD patients. Additionally, PLR abnormalities were noted, including reduced constriction amplitude, pupil constriction ratio, constriction duration, and maximum constriction velocity, along with prolonged latency were observed in BCD patients.</div></div><div><h3>Conclusion</h3><div>BCD patients had significant retinal and vascular changes, along with PLR impairments, especially in patients over 40. More targeted interventions should be focused in future research.</div></div>","PeriodicalId":18534,"journal":{"name":"Microvascular research","volume":"157 ","pages":"Article 104762"},"PeriodicalIF":2.9,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142621727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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