-
Neuron May 2024Recanalization is the mainstay of ischemic stroke treatment. However, even with timely clot removal, many stroke patients recover poorly. Leptomeningeal collaterals...
Recanalization is the mainstay of ischemic stroke treatment. However, even with timely clot removal, many stroke patients recover poorly. Leptomeningeal collaterals (LMCs) are pial anastomotic vessels with yet-unknown functions. We applied laser speckle imaging, ultrafast ultrasound, and two-photon microscopy in a thrombin-based mouse model of stroke and fibrinolytic treatment to show that LMCs maintain cerebral autoregulation and allow for gradual reperfusion, resulting in small infarcts. In mice with poor LMCs, distal arterial segments collapse, and deleterious hyperemia causes hemorrhage and mortality after recanalization. In silico analyses confirm the relevance of LMCs for preserving perfusion in the ischemic region. Accordingly, in stroke patients with poor collaterals undergoing thrombectomy, rapid reperfusion resulted in hemorrhagic transformation and unfavorable recovery. Thus, we identify LMCs as key components regulating reperfusion and preventing futile recanalization after stroke. Future therapeutic interventions should aim to enhance collateral function, allowing for beneficial reperfusion after stroke.
Topics: Animals; Ischemic Stroke; Mice; Collateral Circulation; Humans; Reperfusion; Meninges; Male; Cerebrovascular Circulation; Mice, Inbred C57BL; Disease Models, Animal; Brain; Thrombectomy
PubMed: 38412858
DOI: 10.1016/j.neuron.2024.01.031 -
Chemical and perfusion markers as predictors of moyamoya disease progression and complication types.Scientific Reports Jan 2024To investigate the association between chemical markers (triglyceride, C-reactive protein (CRP), and inflammation markers) and perfusion markers (relative cerebral...
To investigate the association between chemical markers (triglyceride, C-reactive protein (CRP), and inflammation markers) and perfusion markers (relative cerebral vascular reserve (rCVR)) with moyamoya disease progression and complication types. A total of 314 patients diagnosed with moyamoya disease were included. Triglyceride and CRP levels were assessed and categorized based on Korean guidelines for dyslipidemia and CDC/AHA guidelines, respectively. Perfusion markers were evaluated using Diamox SPECT. Cox proportional hazard analysis was performed to examine the relationship between these markers and disease progression, as well as complication types (ischemic stroke, hemorrhagic stroke, and rCVR deterioration). Elevated triglyceride levels (≥ 200) were significantly associated with higher likelihood of end-point events (HR: 2.292, CI 1.00-4.979, P = 0.03). Severe decreased rCVR findings on Diamox SPECT were also significantly associated with end-point events (HR: 3.431, CI 1.254-9.389, P = 0.02). Increased CRP levels and white blood cell (WBC) count were significantly associated with moyamoya disease progression. For hemorrhagic stroke, higher triglyceride levels were significantly associated with end-point events (HR: 5.180, CI 1.355-19.801, P = 0.02). For ischemic stroke, severe decreased rCVR findings on Diamox SPECT (HR: 5.939, CI 1.616-21.829, P < 0.01) and increased CRP levels (HR: 1.465, CI 1.009-2.127, P = 0.05) were significantly associated with end-point events. Elevated triglyceride, CRP, and inflammation markers, as well as decreased rCVR, are potential predictors of moyamoya disease progression and complication types. Further research is warranted to understand their role in disease pathophysiology and treatment strategies.
Topics: Humans; Moyamoya Disease; Acetazolamide; Hemorrhagic Stroke; Perfusion; C-Reactive Protein; Disease Progression; Ischemic Stroke; Inflammation; Triglycerides; Stroke
PubMed: 38167529
DOI: 10.1038/s41598-023-47984-y -
Frontiers in Immunology 2023In response to the increasing demand for lung transplantation, lung perfusion (EVLP) has extended the number of suitable donor lungs by rehabilitating marginal organs....
In response to the increasing demand for lung transplantation, lung perfusion (EVLP) has extended the number of suitable donor lungs by rehabilitating marginal organs. However despite an expanding use in clinical practice, the responses of the different lung cell types to EVLP are not known. In order to advance our mechanistic understanding and establish a refine tool for improvement of EVLP, we conducted a pioneer study involving single cell RNA-seq on human lungs declined for transplantation. Functional enrichment analyses were performed upon integration of data sets generated at 4 h (clinical duration) and 10 h (prolonged duration) from two human lungs processed to EVLP. Pathways related to inflammation were predicted activated in epithelial and blood endothelial cells, in monocyte-derived macrophages and temporally at 4 h in alveolar macrophages. Pathways related to cytoskeleton signaling/organization were predicted reduced in most cell types mainly at 10 h. We identified a division of labor between cell types for the selected expression of cytokine and chemokine genes that varied according to time. Immune cells including CD4 and CD8 T cells, NK cells, mast cells and conventional dendritic cells displayed gene expression patterns indicating blunted activation, already at 4 h in several instances and further more at 10 h. Therefore despite inducing inflammatory responses, EVLP appears to dampen the activation of major lung immune cell types, what may be beneficial to the outcome of transplantation. Our results also support that therapeutics approaches aiming at reducing inflammation upon EVLP should target both the alveolar and vascular compartments.
Topics: Humans; Perfusion; CD8-Positive T-Lymphocytes; Endothelial Cells; Lung Transplantation; Lung; Inflammation
PubMed: 37465668
DOI: 10.3389/fimmu.2023.1142228 -
Experimental Gerontology Nov 2023Severe sarcopenia may result in severe disability. Early diagnosis is currently the key to enhancing the treatment of sarcopenia, and there is an urgent need for a...
An experimental study for quantitative assessment of fatty infiltration and blood flow perfusion in quadriceps muscle of rats using IDEAL-IQ and BOLD-MRI for early diagnosis of sarcopenia.
BACKGROUND
Severe sarcopenia may result in severe disability. Early diagnosis is currently the key to enhancing the treatment of sarcopenia, and there is an urgent need for a highly sensitive and dependable tool to evaluate the course of early sarcopenia in clinical practice. This study aims to investigate longitudinally the early diagnosability of magnetic resonance imaging (MRI)-based fat infiltration and blood flow perfusion technology in sarcopenia progression.
METHODS
48 Sprague-Dawley rats were randomly assigned into six groups that were based on different periods of dexamethasone (DEX) injection (0, 2, 4, 6, 8, 10 days). Multimodal MRI was scanned to assess muscle mass. Grip strength and swimming exhaustion time of rats were measured to assess muscle strength and function. Immunofluorescence staining for CD31 was employed to assess skeletal muscle capillary formation, and western blot was used to detect vascular endothelial growth factor-A (VEGF-A) and muscle ring finger-1 (MuRF-1) protein expression. Subsequently, we analyzed the correlation between imaging and histopathologic parameters. A receiver operating characteristic (ROC) analysis was conducted to assess the effectiveness of quantitative MRI parameters for discriminating diagnosis in both pre- and post-modeling of DEX-induced sarcopenic rats.
RESULTS
Significant differences were found in PDFF, R2* and T2 values on day 2 of DEX-induction compared to the control group, occurring prior to the MRI-CSA values and limb grip strength on day 6 of induction and swimming exhaustion time on day 8 of induction. There is a strong correlation between MRI-CSA with HE-CSA values (r = 0.67; p < 0.001), oil red O (ORO) area with PDFF (r = 0.67; p < 0.001), microvascular density (MVD) (r = -0.79; p < 0.001) and VEGF-A (r = -0.73; p < 0.001) with R2*, MuRF-1 with MRI-CSA (r = -0.82; p < 0.001). The AUC of PDFF, R2*, and T2 values used for modeling evaluation are 0.81, 0.93, and 0.98, respectively.
CONCLUSION
Imaging parameters PDFF, R2*, and T2 can be used to sensitively evaluate early pathological changes in sarcopenia. The successful construction of a sarcopenia rat model can be assessed when PDFF exceeds 1.25, R2* exceeds 53.85, and T2 exceeds 33.88.
Topics: Rats; Animals; Sarcopenia; Vascular Endothelial Growth Factor A; Quadriceps Muscle; Rats, Sprague-Dawley; Magnetic Resonance Imaging; Perfusion; Early Diagnosis
PubMed: 37929293
DOI: 10.1016/j.exger.2023.112322 -
International Journal of Clinical... 2023To evaluate retinal vascular perfusion and density by optical coherence tomography angiography (OCTA) before, during, and after hypoglycemia in individuals with diabetes...
AIM
To evaluate retinal vascular perfusion and density by optical coherence tomography angiography (OCTA) before, during, and after hypoglycemia in individuals with diabetes mellitus with or without diabetic retinopathy (DR).
METHODS
A focused clinical history was performed, followed by an ophthalmological examination to document retinopathy status. OCTA was performed at baseline, at hypoglycemia, and at glucose normalization. Eye tracking and eye alignment devices on the platform were used to obtain a macular thickness cube (512 × 128) and vascular perfusion and density protocols of 3 × 3 mm. Retinal vascular reactivity was analyzed with superficial plexus vascular perfusion and density protocols on OCTA.
RESULTS
Fifty-two participants encompassing 97 eyes fulfilled the eligibility criteria. Their mean age was 42.9 ± 15.1 years (range, 22 to 65), and 20 (38.2%) were men. We found a statistically significant difference in vascular perfusion and density when comparing all groups at baseline. The controls had higher vascular perfusion and density values than the cases. Vascular perfusion and density were significantly reduced in all groups during the hypoglycemia episode, except for vascular density in DR cases.
CONCLUSION
Acute hypoglycemia significantly alters the retinal vascularity in DM patients with and without DR, suggesting that repeated episodes of acute hypoglycemia could exacerbate retinopathy in the long term.
Topics: Male; Humans; Adult; Middle Aged; Female; Microvascular Density; Retinal Vessels; Fluorescein Angiography; Diabetic Retinopathy; Perfusion; Hypoglycemia; Insulins
PubMed: 37876724
DOI: 10.1155/2023/9928582 -
Science Advances Dec 2023Proper placental vascularization is vital for pregnancy outcomes, but assessing it with animal models and human explants has limitations. We introduce a 3D in vitro...
Proper placental vascularization is vital for pregnancy outcomes, but assessing it with animal models and human explants has limitations. We introduce a 3D in vitro model of human placenta terminal villi including fetal mesenchyme and vascular endothelium. By coculturing HUVEC, placental fibroblasts, and pericytes in a macrofluidic chip with a flow reservoir, we generate fully perfusable fetal microvessels. Pressure-driven flow facilitates microvessel growth and remodeling, resulting in early formation of interconnected and lasting placental-like vascular networks. Computational fluid dynamics simulations predict shear forces, which increase microtissue stiffness, decrease diffusivity, and enhance barrier function as shear stress rises. Mass spectrometry analysis reveals enhanced protein expression with flow, including matrix stability regulators, proteins associated with actin dynamics, and cytoskeleton organization. Our model provides a powerful tool for deducing complex in vivo parameters, such as shear stress on developing vascularized placental tissue, and holds promise for unraveling gestational disorders related to the vasculature.
Topics: Animals; Pregnancy; Humans; Female; Placenta; Perfusion; Neovascularization, Pathologic; Coculture Techniques; Microvessels
PubMed: 38134282
DOI: 10.1126/sciadv.adj8540 -
Cellular & Molecular Biology Letters Jul 2023Hepatic ischemia-reperfusion injury (IRI) in donation after cardiac death (DCD) donors is a major determinant of transplantation success. Endoplasmic reticulum (ER)...
BACKGROUND
Hepatic ischemia-reperfusion injury (IRI) in donation after cardiac death (DCD) donors is a major determinant of transplantation success. Endoplasmic reticulum (ER) stress plays a key role in hepatic IRI, with potential involvement of the Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) pathway and the antiapoptotic protein hematopoietic-lineage substrate-1-associated protein X-1 (HAX1). In this study, we aimed to investigate the effects of hypothermic oxygenated perfusion (HOPE), an organ preservation modality, on ER stress and apoptosis during hepatic IRI in a DCD rat model.
METHODS
To investigate whether HOPE could improve IRI in DCD livers, levels of different related proteins were examined by western blotting and quantitative real-time polymerase chain reaction. Further expression analyses, immunohistochemical analyses, immunofluorescence staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, and transmission electron microscopy were conducted to analyze the effects of HOPE on ER stress and apoptosis. To clarify the role of the JAK2/STAT3 pathway and HAX1 in this process, AG490 inhibitor, JAX1 plasmid transfection, co-immunoprecipitation (CO-IP), and flow cytometry analyses were conducted.
RESULTS
HOPE reduced liver injury and inflammation while alleviating ER stress and apoptosis in the DCD rat model. Mechanistically, HOPE inhibited unfolded protein responses by activating the JAK2/STAT3 pathway, thus reducing ER stress and apoptosis. Moreover, the activated JAK2/STAT3 pathway upregulated HAX1, promoting the interaction between HAX1 and SERCA2b to maintain ER calcium homeostasis. Upregulated HAX1 also modulated ER stress and apoptosis by inhibiting the inositol-requiring enzyme 1 (IRE1) pathway.
CONCLUSIONS
JAK2/STAT3-mediated upregulation of HAX1 during HOPE alleviates hepatic ER stress and apoptosis, indicating the JAK2/STAT3/HAX1 pathway as a potential target for IRI management during DCD liver transplantation.
Topics: Animals; Rats; Janus Kinase 2; STAT3 Transcription Factor; Liver; Endoplasmic Reticulum Stress; Perfusion
PubMed: 37438690
DOI: 10.1186/s11658-023-00466-5 -
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi =... Dec 2023Electrical impedance tomography (EIT) is an emerging technology for real-time monitoring based on the impedance differences of different tissues and organs in the human... (Review)
Review
Electrical impedance tomography (EIT) is an emerging technology for real-time monitoring based on the impedance differences of different tissues and organs in the human body. It has been initially applied in clinical research as well as disease diagnosis and treatment. Lung perfusion refers to the blood flow perfusion function of lung tissue, and the occurrence and development of many diseases are closely related to lung perfusion. Therefore, real-time monitoring of lung perfusion is particularly important. The application and development of EIT further promote the monitoring of lung perfusion, and related research has made great progress. This article reviews the principles of EIT imaging, lung perfusion imaging methods, and their clinical applications in recent years, with the aim of providing assistance to clinical and scientific researchers.
Topics: Humans; Electric Impedance; Lung; Tomography, X-Ray Computed; Perfusion; Tomography
PubMed: 38151950
DOI: 10.7507/1001-5515.202302025 -
International Journal of Surgery... Nov 2023The increasing use of extended criteria donors (ECD) sets higher requirements for graft preservation. Machine perfusion (MP) improves orthotopic liver transplantation... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The increasing use of extended criteria donors (ECD) sets higher requirements for graft preservation. Machine perfusion (MP) improves orthotopic liver transplantation (OLT) outcomes, but its effects on different donor types remains unclear. The authors' aim was to assess the effects of hypothermic machine perfusion (HMP), normothermic machine perfusion (NMP), or normothermic regional perfusion (NRP) versus static cold storage (SCS) on different donor types.
MATERIALS AND METHODS
A literature search comparing the efficacy of MP versus SCS in PubMed, Cochrane, and EMBASE database was conducted. A meta-analysis was performed to obtain pooled effects of MP on ECD, donation after circulatory death (DCD), and donor after brainstem death.
RESULTS
Thirty nine studies were included (nine randomized controlled trials and 30 cohort studies). Compared with SCS, HMP significantly reduced the risk of non-anastomotic biliary stricture (NAS) [odds ratio (OR) 0.43, 95% confidence interval (CI) 0.26-0.72], major complications (OR 0.55, 95% CI 0.39-0.78), and early allograft dysfunction (EAD) (OR 0.46, 95% CI 0.32-0.65) and improved 1-year graft survival (OR 2.36, 95% CI 1.55-3.62) in ECD-OLT. HMP also reduced primary non-function (PNF) (OR 0.40, 95% CI 0.18-0.92) and acute rejection (OR 0.62, 95% CI 0.40-0.97). NMP only reduced major complications in ECD-OLT (OR 0.56, 95% CI 0.34-0.94), without favorable effects on other complications and survival. NRP lowered the overall risk of NAS (OR 0.27, 95% CI 0.11-0.68), PNF (OR 0.43, 95% CI 0.22-0.85), and EAD (OR 0.58, 95% CI 0.42-0.80) and meanwhile improved 1-year graft survival (OR 2.40, 95% CI 1.65-3.49) in control DCD-OLT.
CONCLUSIONS
HMP might currently be considered for marginal livers as it comprehensively improves ECD-OLT outcomes. NMP assists some outcomes in ECD-OLT, but more evidence regarding NMP-ECD is warranted. NRP significantly improves DCD-OLT outcomes and is recommended where longer non-touch periods exist.
Topics: Humans; Liver Transplantation; Tissue Donors; Liver; Graft Survival; Perfusion; Organ Preservation
PubMed: 37578436
DOI: 10.1097/JS9.0000000000000661 -
JAMA Network Open Mar 2024Peripheral artery disease (PAD) in diabetes may lead to diabetic foot ulcer and lower-extremities amputation. Glucagon-like peptide 1 receptor agonists have proven... (Randomized Controlled Trial)
Randomized Controlled Trial
IMPORTANCE
Peripheral artery disease (PAD) in diabetes may lead to diabetic foot ulcer and lower-extremities amputation. Glucagon-like peptide 1 receptor agonists have proven cardiovascular benefits in trials of people with type 2 diabetes at high cardiovascular risk.
OBJECTIVE
To examine the effect of liraglutide on peripheral perfusion measured as peripheral transcutaneous oxygen pressure (TcPo2) in individuals with type 2 diabetes and PAD.
DESIGN, SETTING, AND PARTICIPANTS
This open-label randomized clinical trial was conducted between February 1, 2021, and June 30, 2022, with a final follow-up on December 30, 2022, at University of Campania "Luigi Vanvitelli," Naples, Italy. Fifty-five individuals with type 2 diabetes, PAD, and TcPo2 between 30 and 49 mm Hg were included.
INTERVENTIONS
Patients were randomized to receive 1.8 mg of subcutaneous liraglutide or conventional treatment of cardiovascular risk factors (control group) for 6 months.
MAIN OUTCOMES AND MEASURES
Coprimary outcomes were the change from baseline of peripheral perfusion between groups and the comparison of the proportion of individuals who reached 10% increase of TcPo2 from baseline in each group.
RESULTS
Fifty-five participants (mean [SD] age, 67.5 [8.5] years; 43 [78%] male) were randomized (27 to the liraglutide group and 28 to the control group) and analyzed. Participants had a median (IQR) hemoglobin A1c level of 6.9% (6.5%-7.8%) and a mean (SD) TcPo2 of 40.3 (5.7) mm Hg. Transcutaneous Po2 increased over time in both groups, with significant differences favoring the liraglutide group after 6 months (estimated treatment difference, 11.2 mm Hg; 95% CI, 8.0-14.5 mm Hg; P < .001). The 10% increase of TcPo2 occurred in 24 participants (89%) in the liraglutide group and 13 (46%) in the control group (relative risk, 1.91; 95% CI, 1.26-2.90; P < .001). Compared with the control group, individuals in the liraglutide group had a significant reduction of C-reactive protein (-0.4 mg/dL; 95% CI, -0.7 to -0.07 mg/dL; P = .02), urinary albumin to creatinine ratio (-119.4 mg/g; 95% CI, -195.0 to -43.8 mg/g; P = .003), and improvement of 6-minute walking distance (25.1 m; 95% CI, 21.8-28.3 m; P < .001).
CONCLUSIONS AND RELEVANCE
In this randomized clinical trial of people with type 2 diabetes and PAD, liraglutide increased peripheral perfusion detected by TcPo2 measurement during 6 months of treatment. These results support the use of liraglutide to prevent the clinical progression of PAD in individuals with type 2 diabetes.
TRIAL REGISTRATION
ClinicalTrials.gov Identifier: NCT04881110.
Topics: Male; Humans; Aged; Female; Liraglutide; Diabetes Mellitus, Type 2; Perfusion; Peripheral Arterial Disease; Lower Extremity
PubMed: 38470420
DOI: 10.1001/jamanetworkopen.2024.1545