Cardiac failure occurs when the heart fails to adapt to chronic stresses. Reactive oxygen species (ROS)-dependent signaling is implicated in cardiac stress responses, but the role of different ROS ...sources remains unclear. Here we report that NADPH oxidase-4 (Nox4) facilitates cardiac adaptation to chronic stress. Unlike other Nox proteins, Nox4 activity is regulated mainly by its expression level, which increases in cardiomyocytes under stresses such as pressure overload or hypoxia. To investigate the functional role of Nox4 during the cardiac response to stress, we generated mice with a genetic deletion of Nox4 or a cardiomyocyte-targeted overexpression of Nox4. Basal cardiac function was normal in both models, but Nox4-null animals developed exaggerated contractile dysfunction, hypertrophy, and cardiac dilatation during exposure to chronic overload whereas Nox4-transgenic mice were protected. Investigation of mechanisms underlying this protective effect revealed a significant Nox4-dependent preservation of myocardial capillary density after pressure overload. Nox4 enhanced stress-induced activation of cardiomyocyte hypoxia inducible factor 1 and the release of vascular endothelial growth factor, resulting in increased paracrine angiogenic activity. These data indicate that cardiomyocyte Nox4 is a unique inducible regulator of myocardial angiogenesis, a key determinant of cardiac adaptation to overload stress. Our results also have wider relevance to the use of nonspecific antioxidant approaches in cardiac disease and may provide an explanation for the failure of such strategies in many settings.
OBJECTIVE—Increased reactive oxygen species (ROS) production is involved in the pathophysiology of endothelial dysfunction. NADPH oxidase-4 (Nox4) is a ROS-generating enzyme expressed in the ...endothelium, levels of which increase in pathological settings. Recent studies indicate that it generates predominantly hydrogen peroxide (H2O2), but its role in vivo remains unclear.
METHODS AND RESULTS—We generated transgenic mice with endothelium-targeted Nox4 overexpression (Tg) to study the in vivo role of Nox4. Tg demonstrated significantly greater acetylcholine- or histamine-induced vasodilatation than wild-type littermates. This resulted from increased H2O2 production and H2O2-induced hyperpolarization but not altered nitric oxide bioactivity. Tg had lower systemic blood pressure than wild-type littermates, which was normalized by antioxidants.
CONCLUSION—Endothelial Nox4 exerts potentially beneficial effects on vasodilator function and blood pressure that are attributable to H2O2 production. These effects contrast markedly with those reported for Nox1 and Nox2, which involve superoxide-mediated inactivation of nitric oxide. Our results suggest that therapeutic strategies to modulate ROS production in vascular disease may need to separately target individual Nox isoforms.
The mechanism of blue light-induced retinal ganglion cell (RGC) injury is poorly understood. In this study, we established a patented light-emitting diode-based system to study the effects of ...long-term blue light exposure under culture conditions on RGC-5 cells. Long-term blue light exposure significantly reduced cell viability in a time-dependent manner and induced apoptosis and necrosis in RGC-5 cells. Long-term blue light exposure marked an increase in the expression of Bax and active Caspase-3 (p17), which was accompanied by Bcl-2 down-regulation, and displayed features of the mitochondria-dependent apoptosis pathway. Blue light exposure also increased the generation of reactive oxygen species (ROS), and was a strong inducer of ROS-sensitive protein nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) expression. Moreover, blue light exposure constitutively activated p38 mitogen-activated protein kinases and c-Jun NH2-terminal kinase (JNK), as well as induced the phosphorylation of extracellular signal-regulated kinase in the early phase, in blue light-exposed RGC-5 cells. The protein expression of c-jun and c-fos was further enhanced after RGC-5 cells were exposed to blue light. Taken together, these findings indicated that blue light induced RGC-5 cell line death in dependence upon exposure duration. The potential mechanisms for this phenomenon might be via activated mitochondria-dependent apoptosis, increased ROS production and protein expressions of Nrf2 and HO-1, and activated JNK/p38 MAPK signaling pathways.
This study aimed to assess the effectiveness of surgery in the management of vertical compensatory head posture in patients with congenital nystagmus (CN) inherited in an X-linked manner in a Chinese ...family and determine the molecular pathogenesis of this disease.
We studied 18 members belonging to four generations in a family with congenital nystagmus. Parks shift of neutral zone surgeries were performed on 7 patients with vertical compensatory head posture from the family. In addition, head posture, visual acuity, and stereopsis of the 7 patients were evaluated before and 2-years after the displacement surgeries. Gene alternations of the disease were researched by sequencing a candidate gene (FRMD7). From each generation of the family, one patient (including the proband) and one normal control were sampled for Sanger sequencing.
Over a median follow-up period of 2 years, the anomalous head posture, visual acuity, and stereopsis significantly improved postoperatively (P < 0.05). Sanger sequencing revealed that a variant c.586G > T (p.D196Y) in exon 7 of FRMD7 was co-segregated with the disease in this family.
Parks shift of neutral zone surgeries relieved the vertical compensatory head posture and improved visual acuity and stereopsis in the primary position of CN patients. In this study, it was concluded that a missense mutation in exon 7 (c.586G > 7, p.D196Y) in FRMD7 was possibly responsible for the disease in this family.
•Day-time blue light increase alertness in elder people with significant cataracts.•Cataract surgery can increase blue light transmittance.•Blue light perception can be beneficial for the health of ...elder people.
Daytime blue light exposure can reduce fatigue and increase alertness in young healthy adults. Little is known of the daytime blue light influence on alertness in elders. A prospective with-in subject study was carried out in Peking University Third Hospital to evaluate the impact of cataract surgery on visual functions and the electroencephalogram alertness response to blue light stimulus before and after surgery. 14 participants diagnosed with age-related cataract were scheduled for monocular cataract surgery with ultraviolet-filtering intraocular lens (IOL) implantation. Best corrected visual acuity (BCVA), color discrimination and electroencephalogram results were measured before and after surgery. Exposure to blue light resulted in decreased delta (0.25–3.00 Hz) activity and increased beta (13.25–30.00 Hz) activity both before and after cataract surgery. Significant improvements in the BCVA and Farnsworth-Munsell-100-hue total error scores were found after cataract surgery. The partial error scores in the red-yellow, green blue-blue, and blue purple-purple red bands also showed significant differences, with the green blue-blue band showing the most obvious improvement. Day-time blue light stimulus can increase alertness in elderly people with significant cataracts. Cataract surgery with ultraviolet-filtering IOL implantation can increase light, particularly blue light transmittance. Opaque lens removal does not increase the alertness responses to blue light 1 day after surgery. Nevertheless, the increase in light especially blue light perception can be beneficial for the health of elder people in the long run.
Iridocorneal endothelial (ICE) syndrome is a progressive anterior segment disorder that can be tricky to treat. Keratoplasty is commonly used to treat corneal edema in ICE syndrome. However, glaucoma ...is an important risk factor affecting graft survival. To address this question, we designed a retrospective cohort study to evaluate the effect of Spokewise Iridotomy (SI) on Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) Grafts in Iridocorneal Endothelial (ICE) Syndrome.
This was a retrospective cohort study. A total of 29 patients were included; 31 eyes with ICE syndrome underwent DSAEK at Peking University Third Hospital between June 2015 and June 2022, including 11 eyes with combined SI during DSAEK. The aim was to explore the effect of SI on vision, glaucoma control, complications, peripheral anterior synechiae recurrence, endothelial cell count, and graft survival.
The median follow-up time was 30.83 months (mo.) in the SI+Endothelial Keratoplasty (EK) group and 6.17 mo in the EK group. The 2-year cumulative survival rate of grafts in the SI+EK group was 100%, compared with the 6-month and 1-year cumulative survival rates of 80.2 and 63.2%, respectively, in the EK group (
= 0.043). The SI+EK group had a lower incidence of immediate postoperative complications (
= 0.005), fewer postoperative anti-glaucoma medications (AGMs) (
= 0.029), smaller peripheral anterior synechiae recurrence (
= 0.001), and significant visual acuity improvement (
< 0.05). More AGMs were used in failed grafts (
= 0.002).
SI can help control intraocular pressure, improve visual acuity, and increase graft survival after DSAEK in ICE syndrome patients.
NADPH oxidase (Nox)-derived reactive oxygen species (ROS) are known to be involved in angiotensin II-induced hypertension and endothelial dysfunction. Several Nox isoforms are expressed in the vessel ...wall, among which Nox2 is especially abundant in the endothelium. Endothelial Nox2 levels rise during hypertension but little is known about the cell-specific role of endothelial Nox2 in vivo. To address this question, we generated transgenic mice with endothelial-specific overexpression of Nox2 (Tg) and studied the effects on endothelial function and blood pressure. Tg had an about twofold increase in endothelial Nox2 levels which was accompanied by an increase in p22phox levels but no change in levels of other Nox isoforms or endothelial nitric oxide synthase (eNOS). Basal NADPH oxidase activity, endothelial function and blood pressure were unaltered in Tg compared to wild-type littermates. Angiotensin II caused a greater increase in ROS production in Tg compared to wild-type aorta and attenuated acetylcholine-induced vasorelaxation. Both low and high dose chronic angiotensin II infusion increased telemetric ambulatory blood pressure more in Tg compared to wild-type, but with different patterns of BP change and aortic remodeling depending upon the dose of angiotensin II dose. These results indicate that an increase in endothelial Nox2 levels contributes to angiotensin II-induced endothelial dysfunction, vascular remodeling and hypertension.
Abstract
Background
Single-cell technologies have enabled extensive analysis of complex immune composition, phenotype and interactions within tumor, which is crucial in understanding the mechanisms ...behind cancer progression and treatment resistance. Unfortunately, knowledge on cell phenotypes and their spatial interactions has only had limited impact on the pathological stratification of patients in the clinic so far. We explore the relationship between different tumor environments (TMEs) and response to immunotherapy by deciphering the composition and spatial relationships of different cell types.
Methods
Here we used imaging mass cytometry to simultaneously quantify 35 proteins in a spatially resolved manner on tumor tissues from 26 melanoma patients receiving anti-programmed cell death-1 (anti-PD-1) therapy. Using unsupervised clustering, we profiled 662,266 single cells to identify lymphocytes, myeloid derived monocytes, stromal and tumor cells, and characterized TME of different melanomas.
Results
Combined single-cell and spatial analysis reveals highly dynamic TMEs that are characterized with variable tumor and immune cell phenotypes and their spatial organizations in melanomas, and many of these multicellular features are associated with response to anti-PD-1 therapy. We further identify six distinct TME archetypes based on their multicellular compositions, and find that patients with different TME archetypes responded differently to anti-PD-1 therapy. Finally, we find that classifying patients based on the gene expression signature derived from TME archetypes predicts anti-PD-1 therapy response across multiple validation cohorts.
Conclusions
Our results demonstrate the utility of multiplex proteomic imaging technologies in studying complex molecular events in a spatially resolved manner for the development of new strategies for patient stratification and treatment outcome prediction.
Computational protocols for cell type deconvolution from bulk RNA-seq data have been used to understand cellular heterogeneity in disease-related samples, but their performance can be impacted by ...batch effect among datasets. Here, we present a DAISM-DNN protocol to achieve robust cell type proportion estimation on the target dataset. We describe the preparation of calibrated samples from human blood samples. We then detail steps to train a dataset-specific deep neural network (DNN) model and cell type proportion estimation using the trained model.
For complete details on the use and execution of this protocol, please refer to Lin et al. (2022).
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•A protocol for accurate cell type deconvolution with data-driven DNN-based approach•Obtain expression and cell proportions from calibrated samples•DAISM-DNN model training including parameter tuning and data formatting•Trained model can be applied to other biomedical experiments under the same conditions
Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.
Computational protocols for cell type deconvolution from bulk RNA-seq data have been used to understand cellular heterogeneity in disease-related samples, but their performance can be impacted by batch effect among datasets. Here, we present a DAISM-DNN protocol to achieve robust cell type proportion estimation on the target dataset. We describe the preparation of calibrated samples from human blood samples. We then detail steps to train a dataset-specific deep neural network (DNN) model and cell type proportion estimation using the trained model.
A 25-year-old woman with moderate myopia presented for refractive surgery. Bilateral femtosecond laser small-incision lenticule extraction (SMILE) was scheduled and her right eye was completed ...smoothly. However, during the lenticule cutting of her left eye, a large inferior black area was noted. The operation was abandoned after an immediate optical coherence tomography examination, which revealed the corneal epithelium defect with no laser scanning line at the corresponding site. The secondary surgery was assigned to laser-assisted subepithelial keratomileusis (LASEK) after 1 week. The uncorrected distance visual acuity of her left eye recovered to 20/25 on the 12 day and to 20/20 at 3-month follow-up, with ideal corneal topography profiles. Corneal epithelium defect induced by accidental alcohol contact during disinfection was suspected to cause the black area. The management of black area had to be determined according to the location and size. LASEK was a rational substitution for the aborted SMILE.
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