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Tie2 activation promotes choriocapillary regeneration for alleviating neovascular age-related macular degeneration

Choriocapillary loss is a major cause of neovascular age-related macular degeneration (NV-AMD). Although vascular endothelial growth factor (VEGF) blockade for NV-AMD has shown beneficial outcomes, unmet medical needs for patients refractory or tachyphylactic to anti-VEGF therapy exist. In addition, the treatment could exacerbate choriocapillary rarefaction, necessitating advanced treatment for fundamental recovery from NV-AMD. In this study, Tie2 activation by angiopoietin-2–binding and Tie2-activating antibody (ABTAA) presents a therapeutic strategy for NV-AMD. Conditional Tie2 deletion impeded choriocapillary maintenance, rendering eyes susceptible to NV-AMD development. Moreover, in a NV-AMD mouse model, ABTAA not only suppressed choroidal neovascularization (CNV) and vascular leakage but also regenerated the choriocapillaris and relieved hypoxia. Conversely, VEGF blockade degenerated the choriocapillaris and exacerbated hypoxia, although it suppressed CNV and vascular leakage. Together, we establish that angiopoietin-Tie2 signaling is critical for choriocapillary maintenance and that ABTAA represents an alternative, combinative therapeutic strategy for NV-AMD by alleviating anti-VEGF adverse effects.

Neovascular age-related macular degeneration (NV-AMD) is a leading cause of irreversible vision loss among elderly persons in developed countries. NV-AMD is characterized by the formation of choroidal neovascularization (CNV), an ingrowth of abnormal blood vessels from the choroid through Bruch’s membrane into the sub-retinal pigment epithelium (RPE) or subretinal space. Throughout this ingrowth, abnormal leakages of fluids and bloods occur into the retina, causing vision distortion and loss of central vision (2, 3). To treat neovascular eye diseases including NV-AMD, anti–vascular endothelial growth factor A (VEGF) therapy has largely been used based on the fact that an excessive production of VEGF from hypoxic cells in the retino-choroidal complex is critical in the pathogenesis and features of neovascular eye diseases (3, 4).

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Newly discovered hybrid molecules could serve as a novel category of anti-cancer agent

Researchers from NYU Abu Dhabi’s (NYUAD) chemistry program and colleagues from the University’s biology program have developed and studied the biological activity of five new, metal-organic hybrid knotted molecules, termed metal-organic trefoil knots (M-TKs). These molecules can effectively deliver metals to cancer cells, demonstrating the potential to act as a new category of anti-cancer agents.

In a study published in the journal Chemical Science, NYUAD Research Scientists Farah Benyettou and Thirumurugan Prakasam from the Trabolsi Research Group, led by NYUAD Associate Professor of Chemistry Ali Trabolsi, report that these nanoscale, water-soluble M-TKs showed high potency in vitro against six cancer cell lines and in vivo in zebrafish embryos. Zebrafish-related studies were performed by NYUAD Postdoctoral Associate Anjana Ramdas Nair from the Sadler Lab.

The M-TKs, generated by metal-templated self-assembly of a simple pair of chelating ligands, were well tolerated in vitro by non-cancer cells but were significantly more potent than cisplatin, a common chemotherapy medication, in both human cancer cells—including those that were cisplatin-resistant—and in zebrafish embryos. In cultured cells, M-TKs introduce reactive oxygen species (ROS) that damage the mitochondria of cancer cells, but not the nuclear DNA or the plasma membrane.

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Massive sequencing study links rare DNA alterations to type 2 diabetes

An international consortium of scientists has analyzed protein-coding genes from nearly 46,000 people, linking rare DNA alterations to type 2 diabetes. The study, one of the largest known of its type, includes data from people of European, African American, Hispanic/Latino, East Asian, and South Asian ancestries.

From this large cohort—roughly 21,000 individuals with type 2 diabetes and 25,000 healthy controls—the researchers identified four genes with rare variants that affect diabetes risk. The data suggests that hundreds more genes will likely be identified in the future.

These genes and the proteins they encode are potential targets for new medicines, and may guide researchers to better understand and treat disease.

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Civil War plant medicines blast drug-resistant bacteria in lab tests

During the height of the Civil War, the Confederate Surgeon General commissioned a guide to traditional plant remedies of the South, as battlefield physicians faced high rates of infections among the wounded and shortages of conventional medicines. A new study of three of the plants from this guide—the white oak, the tulip poplar and the devil’s walking stick—finds that they have antiseptic properties.

Scientific Reports is publishing the results of the study led by scientists at Emory University. The results show that extracts from the plants have antimicrobial activity against one or more of a trio of dangerous species of multi-drug-resistant bacteria associated with wound infections: Acinetobacter baumannii, Staphylococcus aureus and Klebsiella pneumoniae.

“Our findings suggest that the use of these topical therapies may have saved some limbs, and maybe even lives, during the Civil War,” says Cassandra Quave, senior author of the paper and assistant professor at Emory’s Center for the Study of Human Health and the School of Medicine’s Department of Dermatology.

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