Apolipoprotein E4 impairs the response of neurodegenerative retinal microglia and prevents neuronal loss in glaucoma.

The apolipoprotein E4 (APOE4) allele is associated with an increased risk of Alzheimer disease and a decreased risk of glaucoma, but the underlying mechanisms remain poorly understood. Here, we found that in two mouse glaucoma models, microglia transitioned to a neurodegenerative phenotype characterized by upregulation of Apoe and Lgals3 (Galectin-3), which were also upregulated in human glaucomatous retinas. Mice with targeted deletion of Apoe in microglia or carrying the human APOE4 allele were protected from retinal ganglion cell (RGC) loss, despite elevated intraocular pressure (IOP). Similarly to Apoe-/- retinal microglia, APOE4-expressing microglia did not upregulate neurodegeneration-associated genes, including Lgals3, following IOP elevation. Genetic and pharmacologic targeting of Galectin-3 ameliorated RGC degeneration, and Galectin-3 expression was attenuated in human APOE4 glaucoma samples. These results demonstrate that impaired activation of APOE4 microglia is protective in glaucoma and that the APOE-Galectin-3 signaling can be targeted to treat this blinding disease.

The Role of Gut Microbiota in Glaucoma Progression and Other Retinal Diseases.

As a rapidly growing field, microbiota research offers novel approaches to promoting ocular health and treating major retinal diseases, such as glaucoma. Gut microbiota changes throughout life; however, certain patterns of population changes have been increasingly associated with specific diseases. It has been well established that a disrupted microbiome contributes to central nervous system diseases, including Alzheimer disease, Parkinson disease, multiple sclerosis, and glioma, suggesting a prominent role of microbiome in neurodegenerative diseases. This review summarizes the progress in identifying significant changes in the microbial composition of patients with glaucoma by compiling studies on the association between microbiota and disease progression. Of interest is the relationship between increased Firmicutes/Bacteroidetes ratio in patients with primary open-angle glaucoma, increased taurocholic acid, decreased glutathione, and a reduction in retinal ganglion cell survival. Connecting these microbes to specific metabolites sheds light on the pathogenic mechanism and novel treatment strategies. In summary, the current review synthesizes the findings of several studies investigating the effects of shifting bacterial population in retinal diseases, particularly glaucoma, with the aim to identify the current direction of treatment and help direct future endeavors.

Electrical stimulation alters DNA methylation and promotes neurite outgrowth.

Electrical stimulation (ES) influences neural regeneration and functionality. We here investigate whether ES regulates DNA demethylation, a critical epigenetic event known to influence nerve regeneration. Retinal ganglion cells (RGCs) have long served as a standard model for central nervous system neurons, whose growth and disease development are reportedly affected by DNA methylation. The current study focuses on the ability of ES to rescue RGCs and preserve vision by modulating DNA demethylation. To evaluate DNA demethylation pattern during development, RGCs from mice at different stages of development, were analyzed using qPCR for ten-eleven translocation (TETs) and immunostained for 5 hydroxymethylcytosine (5hmc) and 5 methylcytosine (5mc). To understand the effect of ES on neurite outgrowth and DNA demethylation, cells were subjected to ES at 75 µAmp biphasic ramp for 20 min and cultured for 5 days. ES increased TETs mediated neurite outgrowth, DNA demethylation, TET1 and growth associated protein 43 levels significantly. Immunostaining of PC12 cells following ES for histone 3 lysine 9 trimethylation showed cells attained an antiheterochromatin configuration. Cultured mouse and human retinal explants stained with ß-III tubulin exhibited increased neurite growth following ES. Finally, mice subjected to optic nerve crush injury followed by ES exhibited improved RGCs function and phenotype as validated using electroretinogram and immunohistochemistry. Our results point to a possible therapeutic regulation of DNA demethylation by ES in neurons.

NF-κB activation in retinal microglia is involved in the inflammatory and neovascularization signaling in laser-induced choroidal neovascularization in mice.

PURPOSE: To evaluate Nuclear Factor NF-κB (NF-κB) signaling on microglia activation, migration, and angiogenesis in laser-induced choroidal neovascularization (CNV). METHODS: Nine-week-old C57BL/6 male mice were randomly assigned to IMD-0354 treated or untreated groups (5 mice, 10 eyes per group). CNV was induced with a 532-nm laser. Laser spots (power 250 mW, spot size 100 µm, time of exposure 50 ms) were created in each eye using a slit-lamp delivery system. Selective inhibitor of nuclear factor kappa-B kinase subunit beta (IKK2) inhibitor IMD-0354 (10 µg) was delivered subconjunctivally; vehicle-treated mice were the control. The treatment effect on CNV development was assessed at five days post-CNV induction in vivo in C57BL/6 and Cx3cr1gfp/wt mice by fluorescent angiography, fundus imaging, and ex vivo by retinal flatmounts immunostaining and Western blot analysis of RPE/Choroidal/Scleral complexes (RCSC) lysates. In vitro evaluations of IMD-0354 effects were performed in the BV-2 microglial cell line using lipopolysaccharide (LPS) stimulation. RESULTS: IMD-0354 caused a significant reduction in the fluorescein leakage and size of the laser spot, as well as a reduction in microglial cell migration and suppression of phospho-IκBα, Vascular endothelial growth factor (VEGF-A), and Prostaglandin-endoperoxide synthase 2 (COX-2). In vivo and ex vivo observations demonstrated reduced lesion size in mice, CD68, and Allograft inflammatory factor 1 (IBA-1) positive microglia cells migration to the laser injury site in IMD-0354 treated eyes. The data further corroborate with GFP-positive cells infiltration of the CNV site in Cx3cr1wt/gfp mice. In vitro IMD-0354 (10-25 ng/ml) treatment reduced NF-κB activation, expression of COX-2, caused decreased Actin-F presence and organization, resulting in reduced BV-2 cells migration capacity. CONCLUSION: The present data indicate that NF-κB activation in microglia and it's migration capacity is involved in the development of laser CNV in mice. Its suppression by NF-κB inhibition might be a promising therapeutic strategy for wet AMD.

Transcorneal but not transpalpebral electrical stimulation disrupts mucin homeostasis of the ocular surface.

PURPOSE: Transcorneal electrical stimulation (TcES) is increasingly applied as a therapy for preserving and improving vision in retinal neurodegenerative and ischemic disorders. However, a common complaint about TcES is its induction of eye pain and dryness in the clinic, while the mechanisms remain unknown. METHOD: TcES or transpalpebral ES (TpES) was conducted in C57BL6j mice for 14 days. The contralateral eyes were used as non-stimulated controls. Levels of intracellular [Ca2+] ([Ca2+]i) were assessed by Fura-2AM. The conductance resistances of the eye under various ES conditions were measured in vivo by an oscilloscope. RESULTS: Although TcES did not affect tear production, it significantly induced damage to the ocular surface, as revealed by corneal fluorescein staining that was accompanied by significantly decreased mucin (MUC) 4 expression compared to the control. Similar effects of ES were detected in cultured primary corneal epithelium cells, showing decreased MUC4 and ZO-1 levels after the ES in vitro. In addition, TcES decreased secretion of MUC5AC from the conjunctiva in vivo, which was also corroborated in goblet cell cultures, where ES significantly attenuated carbachol-induced [Ca2+]i increase. In contrast to TcES, transpalpebral ES (TpES) did not induce corneal fluorescein staining while significantly increasing tear production. Importantly, the conductive resistance from orbital skin to the TpES was significantly smaller than that from the cornea to the retina in TcES. CONCLUSION: TcES, but not TpES, induces corneal epithelial damage in mice by disrupting mucin homeostasis. TpES thus may represent a safer and more effective ES approach for treating retinal neurodegeneration clinically.

Epigenetic Regulation of Optic Nerve Development, Protection, and Repair.

Epigenetic factors are known to influence tissue development, functionality, and their response to pathophysiology. This review will focus on different types of epigenetic regulators and their associated molecular apparatus that affect the optic nerve. A comprehensive understanding of epigenetic regulation in optic nerve development and homeostasis will help us unravel novel molecular pathways and pave the way to design blueprints for effective therapeutics to address optic nerve protection, repair, and regeneration.

CD4+ T-Cell Responses Mediate Progressive Neurodegeneration in Experimental Ischemic Retinopathy.

Retinal ischemic events, which result from occlusion of the ocular vasculature share similar causes as those for central nervous system stroke and are among the most common cause of acute and irreversible vision loss in elderly patients. Currently, there is no established treatment, and the condition often leaves patients with seriously impaired vision or blindness. The immune system, particularly T-cell-mediated responses, is thought to be intricately involved, but the exact roles remain elusive. We found that acute ischemia-reperfusion injury to the retina induced a prolonged phase of retinal ganglion cell loss that continued to progress during 8 weeks after the procedure. This phase was accompanied by microglial activation and CD4+ T-cell infiltration into the retina. Adoptive transfer of CD4+ T cells isolated from diseased mice exacerbated retinal ganglion cell loss in mice with retinal reperfusion damage. On the other hand, T-cell deficiency or administration of T-cell or interferon-γ-neutralizing antibody attenuated retinal ganglion cell degeneration and retinal function loss after injury. These findings demonstrate a crucial role for T-cell-mediated responses in the pathogenesis of neural ischemia. These findings point to novel therapeutic targets of limiting or preventing neuron and function loss for currently untreatable conditions of optic neuropathy and/or central nervous system ischemic stroke.

TNFα activates MAPK and Jak-Stat pathways to promote mouse Müller cell proliferation.

Mouse Müller cells, considered as dormant retinal progenitors, often respond to retinal injury by undergoing reactive gliosis rather than displaying neural regenerative responses. Tumor necrosis factor alpha (TNFα) is a key cytokines induced after injury and implicated in mediating inflammatory and neural regenerative responses in zebrafish. To investigate the involvement of TNFα in mouse retinal injury, adult C57BL/6J mice were subjected to light damage for 14 consecutive days. TNFα was elevated in the retina of mice exposed to light damage, which induced Müller cell proliferation in vitro. Affymetrix microarray showed that, in Müller cells, TNFα induces up-regulation of inflammatory and proliferation-related genes, including NFKB2, leukemia inhibitory factor, interleukin-6, janus kinase (Jak) 1, Jak2, signal transducer and activator of transcription (Stat) 1, Stat2, mitogen-activated protein kinase (MAPK) 7, and MAP4K4 but down-regulation of neuroprogenitor genes, including Sox9, Ascl1, Wnt2 and Hes1. Blocking the Jak/Stat and MAPK pathways attenuated TNFα-induced Müller cell proliferation. These results suggest that TNFα may drive the proliferation and inflammatory response, rather than the neural regenerative potential, of mouse Müller cells.

The impact of belatacept on third-party HLA alloantibodies in highly sensitized kidney transplant recipients.

Recent evidence suggests that belatacept reduces the durability of preexisting antibodies to class I and class II human leukocyte antigens (HLAs). In this case series of 163 highly sensitized kidney transplant candidates whose calculated panel-reactive antibody (cPRA) activity was ≥98% to 100%, the impact of belatacept on preexisting HLA antibodies was assessed. Of the 163 candidates, 72 underwent transplantation between December 4, 2014 and April 15, 2017; 60 of these transplanted patients remained on belatacept consecutively for at least 6 months. We observed a decrease in the breadth and/or strength of HLA class I antibodies as assessed by FlowPRA in belatacept-treated patients compared to controls who did not receive belatacept. Specifically, significant HLA antibody reduction was evident for class I (P < .0009). Posttransplant belatacept-treated patients also had a clinically significant reduction in their cPRA compared to controls (P < .01). Collectively, these findings suggest belatacept can reduce HLA class I antibodies in a significant proportion of highly sensitized recipients and could be an option to improve pretransplant compatibility with organ donors.

Activation of muscarinic acetylcholine receptor 1 promotes invasion of hepatocellular carcinoma by inducing epithelial-mesenchymal transition.

Hepatocellular carcinoma is the second leading cause of cancer-related death worldwide. Neural regulation plays an important role in the development of hepatocellular carcinoma, and activation of sympathetic nervous system can promote the migration and invasion of cancer cells. However, little research has been conducted on how the vagus nerve influences hepatocellular carcinoma. In this study, we found that the expression of vesicular acetylcholine transporter, a biomarker of vagus nerve, was associated with hepatocellular carcinoma patients' clinicopathological characteristics by immunohistochemistry. Further, activation of muscarinic acetylcholine receptor 1 (M1R) promoted HepG2 and SMMC-7721 cells migration and invasion and epithelial-mesenchymal transition via PI3K/Akt pathway. Moreover, inhibition of M1R by antagonist or shRNA suppressed hepatocellular carcinoma cells migration and invasion in vitro and in vivo, inhibited epithelial-mesenchymal transition and PI3K/Akt pathway. Therefore, these results indicate that activation of M1R promotes invasion of hepatocellular carcinoma through epithelial-mesenchymal transition and PI3K/Akt pathway.

Norrin maintains malignancy of gastric cancer cells in part through activating AKT signaling.

Human tumorigenesis resembles embryogenesis by aberrant activation of several developmental pathways including Wnt/ß-catenin signaling. Norrin is an atypical ligand for Frizzled receptor that is preferentially expressed in the endothelium to promote retinal vascularization during development. However, its expression pattern and potential roles in human cancers remain unclear. Here we report that Norrin expression is elevated in the parenchymal cells, but not endothelial cells, in gastric cancer (GC). Moreover, Norrin is required for growth and invasion of GC cells and its expression status is associated with unfavorable outcomes. However, analysis of the TGCA database demonstrates that Norrin expression status is not correlated with key target genes of Wnt/ß-catenin signaling. Among several signaling pathways hyperactivated in cancer, Norrin-depleted GC cells also display down-regulated AKT signaling except the canonical Wnt/ß-catenin signaling. Consistently, small molecule-induced cytosolic activation of AKT partially rescues the proliferative and invasive capability of Norrin-depleted cells. Together, these findings suggest a novel role of Norrin in gastric tumorigenesis that could be exploited for adjuvant therapy against the deadly malignancy.

Eradication Efficacy of Modified Dual Therapy Compared with Bismuth-Containing Quadruple Therapy as a First-Line Treatment of Helicobacter pylori.

OBJECTIVES: This study assessed the effectiveness, adverse events, patient adherence, and costs of modified dual therapy compared with bismuth-containing quadruple therapy for treating Helicobacter pylori infection in Chinese patients. We also sought to determine whether modified dual therapy could be used as an alternative first-line treatment for H. pylori infection. METHODS: A total of 232 H. pylori-infected, treatment-naive patients were enrolled in this open-label, randomized controlled clinical trial. Patients were randomly allocated into 2 groups: the 14-day modified dual therapy group and the bismuth-containing quadruple therapy group. Eradication rates, drug-related adverse events, patient compliance, and drug costs were compared between the 2 groups. RESULTS: The modified dual therapy group achieved eradication rates of 87.9%, 91.1%, and 91.1% as determined by the intention-to-treat, per-protocol, and modified intention-to-treat analyses, respectively. The eradication rates were similar compared with the bismuth-containing quadruple therapy group: 89.7%, 91.2%, and 90.4%. In addition, modified dual therapy ameliorated variations in the CYP2C19, IL-1B-511, and H. pylori VacA genotypes. There were no significant differences in the compliance rates between the 2 groups. The modified dual therapy group exhibited significantly less overall side effects compared with the bismuth-containing quadruple therapy group (P < 0.001). Furthermore, the cost of medications in the modified dual therapy was lower compared with that in the bismuth-containing quadruple therapy. CONCLUSIONS: Modified dual therapy at high dose and administration frequency is equally effective and safer and less costly compared with bismuth-containing quadruple therapy.

Neuroinflammation and microglia in glaucoma: time for a paradigm shift.

Glaucoma is a complex neurodegenerative disease with many clinical subtypes. Some of its rare forms include pigmentary glaucoma, uveitic glaucoma and congenital glaucoma. While they all share common features of progressive retinal ganglion cell (RGC) loss, optic nerve damage and corresponding visual field loss, the exact mechanisms underlying glaucomatous neuron loss are not clear. This has largely hindered the development of a real cure for this disease. Elevated intraocular pressure (IOP) is a known major risk factor of glaucoma; however, progressive degeneration of RGCs and axons can also be found in patients with a normal IOP, i.e., normal tension glaucoma (NTG). Interestingly, patients who carry the gain-of-function mutation of the pro-inflammatory gene TBK1 - tumor necrosis factor (TNF) receptor associated factor NF-κB activator (TANK) binding kinase 1 - are at increased risk to develop NTG. This finding suggests a causal link between neuroinflammatory processes and glaucoma. Various studies have reported the presence of neuroinflammatory responses by microglia, astrocytes and other blood-born immune cells in the optic nerve head (ONH) at early stages of experimental glaucoma. Inhibition of certain pro-inflammatory pathways, particularly those associated with microglial activation, appears to be neuroprotective. In this review, we will focus on the inflammatory responses, in particular the proposed roles of microglia, in the pathogenesis of glaucoma.

Small intestinal bacterial overgrowth is associated with Diarrhea-predominant irritable bowel syndrome by increasing mainly Prevotella abundance.

Objective: Diarrhea-predominant irritable bowel syndrome (IBS-D) is the main subtype of IBS, a chronic functional gastrointestinal disorder. Small intestinal bacterial overgrowth (SIBO), which is characterized by dysbiosis of the bowel, causes gastrointestinal symptoms quite similar to IBS-D. However, whether SIBO correlates with IBS-D and its further mechanism remain unknown.Materials and Methods: The study included 60 IBS-D patients that fulfilled Rome IV criteria and 60 healthy controls. All subjects were undergoing a lactose breath test (LBT) to diagnose SIBO. IBS-D patients were further assigned to negative SIBO (SIBO-) subgroup and positive SIBO (SIBO+) subgroup to analyze the scores of symptoms and differences in the fecal microbiota.Results: The prevalence of SIBO in IBS-D patients was higher than that in healthy controls (51.7% vs. 16.7%, p ≤ .001). In addition, IBS-SSS in SIBO+ subgroup was significantly higher than SIBO- subgroup (p = .015). The 16S rRNA analyses showed that composition and abundance of fecal microbiota were obviously different between the two subgroups. There was a remarkable increase in Prevotella in IBS-D patients, especially in IBS-D SIBO+ sufferers. Meanwhile, there were a moderately positive correlation of the abundance of Prevotella (rho = 0.458, p ≤ .001) with IBS-SSS.Conclusion: SIBO is associated with IBS-D, which may be related to alteration in the intestinal microbiota. These findings suggest the potent role of Prevotella in gastrointestinal symptoms between SIBO and IBS-D, thus provide a novel insight into the connection between SIBO and IBS-D.

Development and validation of three machine-learning models for predicting multiple organ failure in moderately severe and severe acute pancreatitis.

BACKGROUND: Multiple organ failure (MOF) is a serious complication of moderately severe (MASP) and severe acute pancreatitis (SAP). This study aimed to develop and assess three machine-learning models to predict MOF. METHODS: Patients with MSAP and SAP who were admitted from July 2014 to June 2017 were included. Firstly, parameters with significant differences between patients with MOF and without MOF were screened out by univariate analysis. Then, support vector machine (SVM), logistic regression analysis (LRA) and artificial neural networks (ANN) models were constructed based on these factors, and five-fold cross-validation was used to train each model. RESULTS: A total of 263 patients were enrolled. Univariate analysis screened out sixteen parameters referring to blood volume, inflammatory, coagulation and renal function to construct machine-learning models. The predictive efficiency of the optimal combinations of features by SVM, LRA, and ANN was almost equal (AUC = 0.840, 0.832, and 0.834, respectively), as well as the Acute Physiology and Chronic Health Evaluation II score (AUC = 0.814, P > 0.05). The common important predictive factors were HCT, K-time, IL-6 and creatinine in three models. CONCLUSIONS: Three machine-learning models can be efficient prognostic tools for predicting MOF in MSAP and SAP. ANN is recommended, which only needs four common parameters.

Polybenzyl Glutamate Biocompatible Scaffold Promotes the Efficiency of Retinal Differentiation toward Retinal Ganglion Cell Lineage from Human-Induced Pluripotent Stem Cells.

Optic neuropathy is one of the leading causes of irreversible blindness caused by retinal ganglion cell (RGC) degeneration. The development of induced pluripotent stem cell (iPSC)-based therapy opens a therapeutic window for RGC degeneration, and tissue engineering may further promote the efficiency of differentiation process of iPSCs. The present study was designed to evaluate the effects of a novel biomimetic polybenzyl glutamate (PBG) scaffold on culturing iPSC-derived RGC progenitors. The iPSC-derived neural spheres cultured on PBG scaffold increased the differentiated retinal neurons and promoted the neurite outgrowth in the RGC progenitor layer. Additionally, iPSCs cultured on PBG scaffold formed the organoid-like structures compared to that of iPSCs cultured on cover glass within the same culture period. With RNA-seq, we found that cells of the PBG group were differentiated toward retinal lineage and may be related to the glutamate signaling pathway. Further ontological analysis and the gene network analysis showed that the differentially expressed genes between cells of the PBG group and the control group were mainly associated with neuronal differentiation, neuronal maturation, and more specifically, retinal differentiation and maturation. The novel electrospinning PBG scaffold is beneficial for culturing iPSC-derived RGC progenitors as well as retinal organoids. Cells cultured on PBG scaffold differentiate effectively and shorten the process of RGC differentiation compared to that of cells cultured on coverslip. The new culture system may be helpful in future disease modeling, pharmacological screening, autologous transplantation, as well as narrowing the gap to clinical application.

De novo belatacept in clinical vascularized composite allotransplantation.

Most immunosuppressive regimens used in clinical vascularized composite allotransplantation (VCA) have been calcineurin inhibitor (CNI)-based. As such, most recipients have experienced CNI-related side effects. Costimulation blockade, specifically CD28/B7 inhibition with belatacept, has emerged as a clinical replacement for CNI-based immunosuppression in kidney transplantation. We have previously shown that belatacept can be used as a centerpiece immunosuppressant for VCA in nonhuman primates, and subsequently reported successful conversion from a CNI-based regimen to a belatacept-based regimen after clinical hand transplantation. We now report on the case of a hand transplant recipient, whom we have successfully treated with a de novo belatacept-based regimen, transitioned to a CNI-free regimen. This case demonstrates that belatacept can provide sufficient prophylaxis from rejection without chronic CNI-associated side effects, a particularly important goal in nonlifesaving solid organ transplants such as VCA.

Rescue of Glaucomatous Neurodegeneration by Differentially Modulating Neuronal Endoplasmic Reticulum Stress Molecules.

UNLABELLED: Axon injury is an early event in neurodegenerative diseases that often leads to retrograde neuronal cell death and progressive permanent loss of vital neuronal functions. The connection of these two obviously sequential degenerative events, however, is elusive. Deciphering the upstream signals that trigger the neurodegeneration cascades in both neuronal soma and axon would be a key step toward developing the effective neuroprotectants that are greatly needed in the clinic. We showed previously that optic nerve injury-induced neuronal endoplasmic reticulum (ER) stress plays an important role in retinal ganglion cell (RGC) death. Using two in vivo mouse models of optic neuropathies (traumatic optic nerve injury and glaucoma) and adeno-associated virus-mediated RGC-specific gene targeting, we now show that differential manipulation of unfolded protein response pathways in opposite directions-inhibition of eukaryotic translation initiation factor 2α-C/EBP homologous protein and activation of X-box binding protein 1-promotes both RGC axons and somata survival and preserves visual function. Our results indicate that axon injury-induced neuronal ER stress plays an important role in both axon degeneration and neuron soma death. Neuronal ER stress is therefore a promising therapeutic target for glaucoma and potentially other types of neurodegeneration. SIGNIFICANCE STATEMENT: Neuron soma and axon degeneration have distinct molecular mechanisms although they are clearly connected after axon injury. We previously demonstrated that axon injury induces neuronal endoplasmic reticulum (ER) stress and that manipulation of ER stress molecules synergistically promotes neuron cell body survival. Here we investigated the possibility that ER stress also plays a role in axon degeneration and whether ER stress modulation preserves neuronal function in neurodegenerative diseases. Our results suggest that neuronal ER stress is a general mechanism of degeneration for both neuronal cell body and axon, and that therapeutic targeting of ER stress produces significant functional recovery.

Comparison of procedural sequences in same-day painless bidirectional endoscopy: Single-center, prospective, randomized study.

BACKGROUND AND AIM: To compare the efficacy and safety of esophagogastroduodenoscopy (EGD)-colonoscopy and colonoscopy-EGD sequences for patients subjected to same-day bidirectional endoscopy under remifentanil and propofol sedation. METHODS: A total of 209 eligible outpatients scheduled for diagnostic same-day bidirectional endoscopy between 16 February 2016 and 30 April 2016 were randomly assigned to the EGD-colonoscopy (n = 106) and colonoscopy-EGD (n = 103) sequence groups. Primary endpoint was total dose of propofol required for the procedure. Secondary endpoints included duration of endoscopy, patient satisfaction, adverse effects, endoscopy findings, and cardiopulmonary responses of the patients. RESULTS: Patients in the two groups were similar in terms of demographic and clinical data (P > 0.05). EGD-colonoscopy sequence group had lesser requirement of propofol for sedation (P < 0.05), faster recovery (P < 0.001), and lesser influence on mean arterial pressure (MAP) during the endoscopy (P < 0.05). Duration of EGD and colonoscopy, patient satisfaction, adverse effects, and pathological findings did not differ between the two groups. CONCLUSIONS: The EGD-colonoscopy sequence may be considered the preferred sequence for same-day bidirectional endoscopy as a result of less cardiovascular stress, lessened need for sedation with propofol, and faster recovery.