Transthoracic echocardiography monitoring during atrial septal defect and ventricular septal defect device closures using a three-dimensional printed transducer holder.

Transthoracic echocardiography (TTE) is noninvasive but can only be performed intermittently during fluoroscopy. In a prior study, we created a transducer holder device to allow for hemodynamic monitoring in the intensive care unit. The current study is the first instance of the use of a three-dimensional (3D)-printed TTE transducer holder, which is easily customized and personalized to a previous transducer holder at relatively low cost and short production time, to enable continuous TTE monitoring during device closure of an atrial septal defect (ASD) and ventricular septal defect (VSD). There were 14 ASD patients and 9 VSD patients scheduled to undergo device closure. The study's real-time TTE monitoring was performed by using a 3D-printed transducer holder over the course of the entire implantation procedure. There were 23 patients who successfully underwent septal closures using the 3D-printed holder that enabled real-time images over the entire procedure. The median duration for real-time TTE guidance was 15 minutes for the ASD and 36 minutes for the VSD and the median fluoroscopy time was 11 minutes for the ASD and 30 minutes for the VSD. One migrating VSD occluder and one case of aortic regurgitation after occluder deployment were noted by real-time TTE monitoring during the procedure. Our novel 3D-printed transducer holder can provide transesophageal echocardiography-like real-time imaging during device closure of an ASD and a VSD and may become a new alternative method in ASD and VSD closures. It can also prevent radiation exposure for the intervention team who would otherwise need to perform TTE during live fluoroscopy.

Minocycline exhibits synergism with conditioned medium of bone marrow mesenchymal stem cells against ischemic stroke.

Several lines of evidence show that a conditioned medium of bone marrow mesenchymal stem cells (BM-MSCcm) improve functional recovery after ischemic stroke but do not reduce ischemic lesions. It is important to develop a treatment strategy that can exhibit a synergistic effect with BM-MSCcm against ischemic stroke. In this study, the effect of BM-MSCcm and/or minocycline was examined in culture and in a middle cerebral artery occlusion (MCAo) animal model. In neuron-glial cultures, BM-MSCcm and combined treatment, but not minocycline, effectively increased neuronal connection and oligodendroglial survival. In contrast, minocycline and combined treatment, but not BM-MSCcm, reduced toxin-induced free radical production in cultures. Either minocycline or BM-MSCcm, or in combination, conferred protective effects against oxygen glucose deprivation-induced cell damage. In an in vivo study, BM-MSCcm and minocycline were administered to rats 2 h after MCAo. Monotherapy with BM-MSCcm or minocycline after ischemic stroke resulted in 9.4% or 17.5% reduction in infarction volume, respectively, but there was no significant difference. Interestingly, there was a 33.9% significant reduction in infarction volume by combined treatment with BM-MSCcm and minocycline in an in vivo study. The combined therapy also significantly improved grasping power, which was not altered by monotherapy. Furthermore, combined therapy increased the expression of neuronal nuclei in the peri-infarct area and hippocampus, and concurrently decreased the expression of ED1 in rat brain and the peri-infarct zone. Our data suggest that minocycline exhibits a synergistic effect with BM-MSCcm against ischemic stroke not only to improve neurological functional outcome but also to reduce cerebral infarction.

Transthoracic echocardiography monitoring during ASD closure using an artificial hand system.

AIM: Continuous real-time echocardiographic monitoring is essential for guidance during ASD closure. However, transthoracic echocardiography (TTE) can only be implemented intermittently during fluoroscopy. We evaluate a novel approach to provide real-time imaging during the entire procedure. FINDING: We developed a custom-made TTE monitoring apparatus using artificial hand (AH-TTE) that enables real-time TTE images during atrial septal defect (ASD) closure. Thirty-two patients underwent successful device implantation using AH-TTE monitoring without complications. The median duration for real-time AH-TTE monitoring was 22 min and the median fluoroscopy time was 7.2 min. One case of pericardial effusion and one of transient bradycardia event due to air embolism was detected. All patients had uneventful recoveries. CONCLUSIONS: Our simple and novel monitoring technique with AH-TTE provides TEE-like monitoring and may be a new alternative method for ASD closure. It gives real-time stable TTE images and minimizes radiation exposure for the interventional team during fluoroscopy.

Exogenous GDF11 attenuates non-canonical TGF-ß signaling to protect the heart from acute myocardial ischemia-reperfusion injury.

Growth differentiation factor 11 (GDF11) is a member of the transforming growth factor beta 1 (TGF-ß1) superfamily that reverses age-related cardiac hypertrophy, improves muscle regeneration and angiogenesis, and maintains progenitor cells in injured tissue. Recently, targeted myocardial delivery of the GDF11 gene in aged mice was found to reduce heart failure and enhance the proliferation of cardiac progenitor cells after myocardial ischemia-reperfusion (I-R). No investigations have as yet explored the cardioprotective effect of exogenous recombinant GDF11 in acute I-R injury, despite the convenience of its clinical application. We sought to determine whether exogenous recombinant GDF11 protects against acute myocardial I-R injury and investigate the underlying mechanism in Sprague-Dawley rats. We found that GDF11 reduced arrhythmia severity and successfully attenuated myocardial infarction; GDF11 also increased cardiac function after I-R, enhanced HO-1 expression and decreased oxidative damage. GDF11 activated the canonical TGF-ß signaling pathway and inactivated the non-canonical pathways, ERK and JNK signaling pathways. Moreover, administration of GDF11 prior to reperfusion protected the heart from reperfusion damage. Notably, pretreatment with the activin-binding protein, follistatin (FST), inhibited the cardioprotective effects of GDF11 by blocking its activation of Smad2/3 signaling and its inactivation of detrimental TGF-ß signaling. Our data suggest that exogenous GDF11 has cardioprotective effects and may have morphologic and functional recovery in the early stage of myocardial I-R injury. GDF11 may be an innovative therapeutic approach for reducing myocardial I-R injury.

Tailored Holder for Continuous Echocardiographic Monitoring.

Hemodynamic monitoring is essential for prompt and effective interventions in intensive care unit patients. We developed a custom-made transthoracic echocardiography transducer holder consisting of transducer holder and skin patch attachment. This holder allowed continuous transthoracic echocardiography monitoring in 5 adult patients with circulatory failure due to shock, and 6 pediatric patients after successful percutaneous closure of a ventricular septal defect. One case of an unexpected hemopericardium was promptly diagnosed and pericardiocentesis was performed, and 1 patient required extracorporeal membrane oxygenation support.

Transesophageal echocardiography for incremental value of Amplatezer cribriform septal occluder for percutaneous transcatheter closure of complex septal defects: Case series.

BACKGROUND: The anatomy of septal defects can be complex and morphologically unpredictable. Balloon sizing of such defects may not be feasible, and an appropriately sized commercial occluder may not be available. Therefore, percutaneous transcatheter closure of such defects can be challenging because of an increased risk of complications. In this study, we have described the efficacy and safety of transcatheter closure of complex septal defects using Amplatzer cribriform occluder devices, assessed by real time three-dimensional (RT 3D) color Doppler transesophageal echocardiography (TEE). METHODS AND RESULTS: Four complex septal defects were involved in this investigation: (1) reimplanted multiple atrial septal defects (ASD) with one device embolization; (2) postinfarction ventricular septal defect; (3) long tunnel patent foramen ovale; and (4) postoperative residual ASD. All patients underwent percutaneous transcatheter interventions due to the high risk of surgical complications, and one of the three available cribriform ASD device sizes (18 mm, 25 mm, or 35 mm) was implanted. Perioperative RT 3D TEE combined with fluoroscopy was used for monitoring during the procedure. All defects were successfully occluded by cribriform septal occluder devices using the transcatheter technique. CONCLUSION: Our patients with complex septal defects were successfully treated by transcatheter closure using an Amplazter cribriform septal occluder device with careful planning based on patient presentation and close interdisciplinary collaboration. RT 3D color Doppler TEE provided precise information for the selection of the appropriate occluder device and facilitated the procedure by guiding the catheter through the often challenging patient anatomy.

Transcatheter Closure of Atrial Septal Defect with Attenuated Anterior Rim after Transcatheter Aortic Valve Implantation: Can It Be Carried out as a Single Procedure?

Transcatheter aortic valve replacement (TAVR) has emerged as a highly effective minimally invasive treatment for symptomatically critical aortic stenosis (AS) in patients at high or prohibitive surgical risk. We report a case of staged transcatheter management of critical AS combined with an atrial septal defect (ASD) with attenuated anterior superior rim. The clinical result of this case suggests that both procedures can be safely performed simultaneously. Therefore, combined transcatheter treatment may appear as a possible strategy in patients with concomitant cardiac conditions.

Abnormal mitral-aortic intervalvular coupling in mitral valve diseases: a study using real-time three-dimensional transesophageal echocardiography.

BACKGROUND: Mitral and aortic valves are coupled via fibrous tissue. This coupling is considered to be important for cardiac function before and after mitral valve surgery. The relationship between mitral-aortic coupling and different types of mitral regurgitation (MR) is not completely understood. METHODS AND RESULTS: Real-time three-dimensional transesophageal echocardiography (RT3D-TEE) was performed in 133 subjects: 30 normal subjects, 15 patients with Carpentier type I MR (annular dilatation and congenital cleft), 40 type II (mitral valve prolapse), 20 type IIIa (rheumatic) and 28 type IIIb (ischemic mitral regurgitation). Custom software was used to track mitral (MA) and aortic annuli (AoA) in 3D space throughout cardiac cycle, allowing measurement of changes in mitral and aortic valve morphology. Normal mitral-aortic coupling is characterized by reciprocal changes in the annular areas throughout cardiac cycle, with systolic reduction of the angle between the two annular planes. In Carpentier type II patients, not only MA but also AoA areas were increased (P < 0.05 vs normal), but the reciprocal pattern of mitral-aortic coupling was preserved. In both type I IMR and IIIb patients, MA and AoA areas were both increased (P < 0.05 vs normal) and the reciprocal behavior of mitral-aortic coupling was lost. Only MA area was increased in type IIIa patients. The extent of mitral-aortic angle reduction during systole was diminished in all 4 Carpentier groups (P < 0.05 vs normal). CONCLUSIONS: Mitral valve diseases may affect normal mitral-aortic coupling and aortic valve function. Different patterns of abnormal mitral-aortic coupling are associated with different Carpentier types of MR.

Transcatheter Aortic Valve Implantation in a Woman with Porcelain Aorta, Previous Sternotomy for Coronary Artery Bypass Grafting, and Critical Aortic Stenosis.

UNLABELLED: A 74-year-old woman who was diagnosed with right breast cancer at age 39 had been treated with mastectomy, and repeated cycles of chemotherapy and radiotherapy. She also had a history of coronary artery disease, wherein two coronary artery bypass grafts were performed 3 years ago. At that time, porcelain aorta was detected during surgery. In the year prior to admission, the patient presented with severe symptomatic critical aortic stenosis. Due to the prohibitively high surgical risk and need for aortic valve replacement, she underwent successful transcatheter aortic valve implantation with transfemoral implantation of a 29 mm Medtronic CoreValve prosthesis. The patient experienced a good result with reduction of the transaortic gradient and mild residual aortic regurgitation. KEY WORDS: Aortic stenosis; Coronary artery bypass grafting; Porcelain aorta; Radiation; Transcatheter aortic valve implantation.

Intraoperative three-dimensional transesophageal echocardiography for assessing the defect geometries of mitral prosthetic paravalvular leak during transcatheter closure.

BACKGROUND: Paravalvular leaks (PVLs) are a common complication of prosthetic valve replacement. Use of the transcatheter intervention technique is a suitable alternative in high-risk patients who may not tolerate repeat surgery. Common reasons for failure of this demanding intervention include poor imaging quality and unsuitable anatomy. The purpose of this study was to assess the usefulness and the incremental value of real-time three-dimensional (RT 3D) transesophageal echocardiography (TEE) over two-dimensional (2D) TEE findings in the evaluation of the geometry and track of mitral PVLs during transcatheter closure. METHODS: Five patients with six mitral PVLs at high risk for repeat surgery underwent transcatheter leak closure. Intraoperative RT 3DTEE was used to assess the location, shape, number, and size of the defects. Transapical approaches were used in all cases with fluoroscopic and RT 3D TEE guidance of the wire and catheter, device positioning, and assessment of residual leak after the procedure. RESULTS: In all of the cases, defects with irregular crescent shapes and distorted tracks were clearly delineated by RT 3D TEE. This was compared to those results obtained through 2D TEE, which was unable to characterize the defects. Three cases showed small leaks, which were completely occluded with a patent ductus arteriosus (PDA) device in two cases, and a muscular ventricular septal defect (mVSD) occluder combined with coil devices in one case. One case involved a large leak and early device embolization of the muscular VSD occluder, which was removed surgically, and demonstrated a crescent-shaped defect. One patient had two releaks 2 months subsequent to the procedure due to two new extended leaks at the tails of the crescent-shaped defect. CONCLUSION: RT 3D TEE can clearly delineate the geometries of defects in their entirety, including shape, size, and location of the defect and track canal. It would also appear that RT 3D TEE is superior to 2D TEE in the process of guiding the wire through the difficult canal anatomy, facilitating the overall procedure. The small mitral PVLs can be completely occluded, but subsequent complications occurred with large defect closures because of embolization or releak. Therefore, transcatheter closure of PVLs seems to be an attractive alternative for these patients, but newer occluder designs that better conform to leak geometry will be required to improve outcomes.

Percutaneous transcatheter closure of mitral paravalvular leak via transarterial retrograde approach.

Repeat surgery has usually been considered the first choice to solve paravalvular leaks of prosthetic valves, but it carries a high operative risk, a high mortality rate and an increased risk for re-leaks. Percutaneous closure of such defects is possible, and different approaches and devices are used for this purpose. For mitral paravalvular leaks, constructing an arterio-venous wire loop for delivering the closure device through an antegrade approach is the most commonly used technique. Transcatheter closure can also be performed through a transapical approach or retrograde transfemoral arterial approach. We present a case of 68-year-old man with a mitral paravalvular leak that was successfully closed using an Amplatzer(®) Duct Occluder II, via retrograde transfemoral arterial approach under three-dimensional transesophageal echocardiographic guidance, without the use of a wire loop. The initial attempt to cross the paravalvular defect was unsuccessful, but the obstacle was finally overcome by introducing complex interventional techniques.

The role of adenosine in preconditioning by brief pressure overload in rats.

BACKGROUND/PURPOSE: Brief pressure overload of the left ventricle reduced myocardial infarct (MI) size in rabbits has been previously reported. Its effects in other species are not known. This study investigates effects of pressure overload and the role of adenosine in rats in this study. METHODS: MI was induced by 40-minute occlusion of the left anterior descending coronary artery followed by 3-hour reperfusion. MI size was determined by triphenyl tetrazolium chloride staining. Brief pressure overload was induced by two 10-minute episodes of partial snaring of the ascending aorta. Systolic left ventricular pressure was raised 50% above the baseline value. Ischemic preconditioning was elicited by two 10-minute coronary artery occlusions. RESULTS: The MI size (mean ± standard deviation), expressed as percentage of area at risk, was significantly reduced in the pressure overload group as well as in the ischemic preconditioning group (17.4 ± 3.0% and 18.2 ± 1.5% vs. 26.6 ± 2.4% in the control group, p < 0.001). Pretreatment with 8-(p-sulfophenyl)-theophylline (SPT), an inhibitor of adenosine receptors, did not significantly limit the protection by pressure overload and ischemic preconditioning (18.3 ± 1.5% and 18.2 ± 2.0%, respectively, p < 0.001). SPT itself did not affect the extent of infarct (25.4 ± 2.0%). The hemodynamics, area at risk and mortality were not significantly different among all groups of animals. CONCLUSION: Brief pressure overload of the left ventricle preconditioned rat myocardium against infarction. Because SPT did not significantly alter MI size reduction, our results did not support a role of adenosine in preconditioning by pressure overload in rats.

Dynamic assessment of the changing geometry of the mitral apparatus in 3D could stratify abnormalities in functional mitral regurgitation and potentially guide therapy.

INTRODUCTION: In functional mitral regurgitation (FMR), effective regurgitant orifice area (EROA) displays a dynamic pattern. The impact of dynamic changes of annulus dysfunction and leaflets tenting on phasic EROA was explored with real-time three-dimensional transesophageal echocardiography (RT3D-TEE). METHODS: RT3D-TEE was performed in 52 FMR patients and 30 controls. Mitral annulus dimensions and leaflets tenting were measured throughout systole (TomTec, Germany). Phasic EROA was measured by proximal isovelocity surface area (PISA) method. RESULTS: Mitral annulus had the minimal area and an oval shape with saddle configuration during early systole in controls, which enlarged and became round and flattened towards mid and late systole (P<0.05). In contrast, annulus in FMR was significantly larger, rounder and flatter (P<0.001), which further dilated and became more flattened at late systole (P<0.05 vs control). Leaflet tenting height in FMR decreased in mid systole and remains unchanged towards late systole. The leaflet tenting volume peaked at early and late systole with a mid-systolic trough in both FMR and controls. But tenting volume of patients with FMR was significantly larger than that of controls (all P<0.001 vs control in whole systole). Further analysis demonstrated that early tenting volume (ß value=0.053, P<0.05) was a predictor of early EROA, whereas late tenting volume (ß value=0.031, P<0.05) and late annular displacement velocity were predictors of late EROA. CONCLUSIONS: The early and late peak EROAs of FMR was primarily contributed by tenting volume at early systole and late systole respectively. These findings would be of value to consider in interventions aimed at reducing the severity of FMR.

Transcatheter intervention for complex ascending aortic pseudoaneurysm after cardiac surgery.

BACKGROUND: Ascending aortic pseudoaneurysm (PsA) is an uncommon but surgically challenging problem with high morbidity and mortality. Herein we describe the efficacy and safety of the different approaches to transcatheter intervention for repair of ascending PsA and assess the selection of occluder devices using real-time 3-dimensional (RT 3D) color Doppler transesophageal echocardiography (TEE).METHODS AND RESULTS: Three patients with complex ascending PsA after cardiac or aortic root surgery were treated with transcatheter intervention due to high risk for redo surgery. Perioperative RT 3D-TEE combined with fluoroscopy was used for monitoring. All ascending PsA were successfully occluded with different devices using the transcatheter technique either with the transapical, transarterial approach, or transvenous combined with hybrid process depending on lesion anatomy. CONCLUSIONS: Treatment of complex ascending PsA with transcatheter or combined hybrid intervention with cautious planning based on patient presentation and well-coordinated teamwork was successful. RT 3D color Doppler TEE provided precise information for the selection of appropriate occluder device, and also facilitated the procedure by guiding the catheter through difficult anatomy.

Recovery of neurological function of ischemic stroke by application of conditioned medium of bone marrow mesenchymal stem cells derived from normal and cerebral ischemia rats.

BACKGROUND: Several lines of evidence have demonstrated that bone marrow-derived mesenchymal stem cells (BM-MSC) release bioactive factors and provide neuroprotection for CNS injury. However, it remains elusive whether BM-MSC derived from healthy donors or stroke patients provides equal therapeutic potential. The present work aims to characterize BM-MSC prepared from normal healthy rats (NormBM-MSC) and cerebral ischemia rats (IschBM-MSC), and examine the effects of their conditioned medium (Cm) on ischemic stroke animal model. RESULTS: Isolated NormBM-MSC or IschBM-MSC formed fibroblastic like morphology and expressed CD29, CD90 and CD44 but failed to express the hematopoietic marker CD34. The number of colony formation of BM-MSC was more abundant in IschBM-MSC than in NormBM-MSC. This is in contrast to the amount of Ficoll-fractionated mononuclear cells from normal donor and ischemic rats. The effect of cm of BM-MSC was further examined in cultures and in middle cerebral artery occlusion (MCAo) animal model. Both NormBM-MSC Cm and IschBM-MSC Cm effectively increased neuronal connection and survival in mixed neuron-glial cultures. In vivo, intravenous infusion of NormBM-MSC Cm and IschBM-MSC Cm after stroke onset remarkably improved functional recovery. Furthermore, NormBM-MSC Cm and IschBM-MSC Cm increased neurogenesis and attenuated microglia/ macrophage infiltration in MCAo rat brains. CONCLUSIONS: Our data suggest equal effectiveness of BM-MSC Cm derived from ischemic animals or from a normal population. Our results thus revealed the potential of BM-MSC Cm on treatment of ischemic stroke.

Transcatheter Repair of Iatrogenic Aortic Perforation Complicating Transseptal Puncture for a Catheter Ablation of Atrial Arrhythmia.

UNLABELLED: Aortic root perforation is a potentially life-threatening complication that may occur during transseptal puncture and requires immediate repair. We present a 71-year-old man who was admitted for catheter ablation of persistent atypical atrial flutter. Fluoroscopic-guided transseptal puncture was performed to gain access to the left atrium. An unrecognized puncture of the aortic root by Brockenbrough needle and inadvertent advancement of Mullins sheath resulted in aortic root perforation. We decided to seal the hole transcatheterly with an occluder device. Severe aortic regurgitation (AR) was noted by transesophageal echocardiography after deployment of a 6 mm Amplatzer septal occluder (ASO). Thereafter, we switched to a 6/4-mm Amplatzer duct occluder (ADO) and only minimal AR was noted after deployment. This is because the diameter of the left atrial disc of ASO is larger than the diameter of the retention skirt of ADO to interfere with the movement of aortic valve leaflet. During 6 months of echocardiographic follow-up, the ADO remained in place and no residual shunt was observed. KEY WORDS: Aortic perforation; Transcatheter repair; Transseptal puncture.

The role of transesophageal echocardiography in clinical use.

Transesophageal echocardiography (TEE) is not only an invaluable diagnostic tool for cardiac patients, but also is essential for cardiac monitoring in critically ill patients in cardiac and non-cardiac surgery settings and in the differential diagnosis of unexplained hemodynamic collapse. The advantage of TEE over transthoracic echocardiography (TTE) is usually clearer images, especially when viewing structures that are difficult to see transthoracically. TEE is essential in monitoring adult and congenital heart surgery perioperatively. The adequacy of the repair can be ensured immediately through a review of TEE images directly after surgery. Although TEE is considered to be relatively safe and noninvasive, TEE-associated complications, such as esophageal laceration, must be taken seriously. Recently, real-time three-dimensional (3D) TEE imaging has played an important role defining valvular and congenital abnormalities and aiding in operative and percutaneous repair.

The additional value of live/real-time three-dimensional transesophageal echocardiography over two-dimensional transesophageal echocardiography for assessing mitral regurgitation with eccentric jets.

BACKGROUND: Two-dimensional transesophageal echocardiography (2D TEE) Doppler color flow imaging is the gold standard for assessing the severity of mitral regurgitation (MR). Severe MR with very eccentric jet may involve more than one mitral leaflet lesion and can be missed by 2D TEE. The purpose of this study was to assess the usefulness and the incremental value of real-time three-dimensional (RT 3D) TEE over 2D TEE findings in the evaluation of patients suffering eccentric MR with more than one mitral leaflet lesion. METHODS: Intraoperative 2D TEE and RT 3D TEE examinations were performed on 168 patients with Carpenter II MR who underwent surgery. MR was defined as either central, free-standing eccentric jet or very eccentric jet. 2D TEE and RT 3D TEE finding were compared with surgical findings. RESULTS: Of these 168 MR patients, 25 patients (14.9%) had central jets and 143 patients (85.1%) had eccentric jets. Among 143 patients with eccentric jets, 47 patients (32.9%) had free-standing eccentric MR jets, and 96 (67.1%) patients had very eccentric jets. 3D TEE diagnosed the severity and location of MR lesions correctly in all patients; this was not the case with 2D TEE, which had significant diagnostic misses in nine patients (9.4%, p < 0.001) having MR with very eccentric jets. These nine patients had lesions on both mitral leaflets, which were missed during 2D TEE examination owing to the highly turbulent flows produced by very eccentric jets from one mitral leaflet lesion and impinging the opposite mitral leaflet lesion. CONCLUSION: The severity of MR with very eccentric jet was more accurately and comprehensively assessed by 3D TEE than by 2D TEE. Therefore, intraoperative RT 3D TEE provides incremental information that is generally superior to 2D TEE in patients with complex MR due to very eccentric jets.

Baicalein protects against retinal ischemia by antioxidation, antiapoptosis, downregulation of HIF-1α, VEGF, and MMP-9 and upregulation of HO-1.

PURPOSE: Retinal ischemia-associated ocular disorders are vision threatening. This study examined whether the flavonoid baicalein is able to protect against retinal ischemia/reperfusion. METHODS: Using rats, the intraocular pressure was raised to 120 mmHg for 60 min to induce retinal ischemia. In vitro, an ischemic-like insult, namely oxidative stress, was established by incubating dissociated retinal cells with 100 µM ascorbate and 5 µM FeSO4 (iron) for 1 h. The rats or the dissociated cells had been pretreated with baicalein (in vivo: 0.05 or 0.5 nmol; in vitro: 100 µM), vehicle (1% ethanol), or trolox (in vivo: 5 nmol; in vitro: 100 µM or 1 mM). The effects of these treatments on the retina or the retinal cells were evaluated by electrophysiology, immunohistochemistry, terminal deoxynucleotidyl-transferase-mediated dUTP nick end-labeling (TUNEL) staining, Western blotting, or in vitro dichlorofluorescein assay. In addition, real-time-polymerase chain reaction was used to assess the retinal expression of hypoxia-inducible factor-1α (HIF-1α), matrix metalloproteinase-9 (MMP-9), vascular endothelium growth factor (VEGF), and heme oxygenase-1 (HO-1). RESULTS: The retinal changes after ischemia included a decrease in the electroretinogram b-wave amplitude, a loss of choline acetyltransferase immunolabeling amacrine cell bodies/neuronal processes, an increase in vimentin immunoreactivity, which is a marker for Müller cells, an increase in apoptotic cells in the retinal ganglion cell layer linked to a decrease in the Bcl-2 protein, and changes in the mRNA levels of HIF-1α, VEGF, MMP-9, and HO-1. Of clinical importance, the ischemic detrimental effects were concentration dependently and/or significantly (0.05 nmol and/or 0.5 nmol) altered when baicalein was applied 15 min before retinal ischemia. Most of all, 0.5 nmol baicalein significantly reduced the upregulation of MMP-9; in contrast, 5 nmol trolox only had a weak attenuating effect. In dissociated retinal cells subjected to ascorbate/iron, there was an increase in the levels of reactive oxygen species, which had been significantly attenuated by 100 µM baicalein and trolox (100 µM or 1 mM; a stronger antioxidative effect at 1 mM). CONCLUSIONS: Baicalein would seem to protect against retinal ischemia via antioxidation, antiapoptosis, upregulation of HO-1, and downregulation of HIF-1α, VEGF, and MMP-9. The antioxidative effect of baicalein would appear to play a minor role in downregulation of MMP-9.

Anti-oxidative, anti-apoptotic, and pro-angiogenic effects mediate functional improvement by sonic hedgehog against focal cerebral ischemia in rats.

Sonic hedgehog (SHH) is a morphogen important for neural development during embryogenesis. Recently, beneficial actions of SHH in ischemic injury have been noted. To test whether epidural application of the biolgically active N-terminal fragment of SHH (SHH-N) may reduce the extent of ischemic brain injury, male Long-Evans rats were exposed to a 60-min episode of middle cerebral artery occlusion (MCAO) with topical application of SHH-N and/or its specific inhibitor, cyclopamine, in fibrin glue over the peri-infarct cortex. We found that epidural application of SHH-N substaintially reduced infarct volumes after 7 days of reperfusion, which was reversed by cyclopamine; SHH-N also improved behavioral outcomes as assessed by global neurological functions, rotarod test, and grasping power test. Furthermore, SHH-N attenuated the extents of protein oxidation, lipid peroxidation, and apoptosis induced by focal ischemia/reperfusion. Immunohistochemical staining coupled with bromodeoxyuridine (BrdU) incorporation revealed that SHH-N enhanced post-ischemic angiogenesis, stimulated the proliferation of nestin-positive (nestin(+)) neural progenitor cells (NPCs), and suppressed astrocytosis. Our results thus revealed multifaceted protective mechanisms of SHH-N against focal cerebral ischemia/reperfusion.