Therapeutic drugs with ototoxic side effects cause significant hearing loss for thousands of patients annually. Two major classes of ototoxic drugs are cisplatin and the aminoglycoside antibiotics, both of which are toxic to mechanosensory hair cells, the receptor cells of the inner ear. A critical need exists for therapies that protect the inner ear without inhibiting the therapeutic efficacy of these drugs. The induction of heat shock proteins (HSPs) inhibits both aminoglycoside- and cisplatin-induced hair cell death and hearing loss. We hypothesized that exposure to sound that is titrated to stress the inner ear without causing permanent damage would induce HSPs in the cochlea and inhibit ototoxic drug–induced hearing loss. We developed a sound exposure protocol that induces HSPs without causing permanent hearing loss. We used this protocol in conjunction with a newly developed mouse model of cisplatin ototoxicity and found that preconditioning mouse inner ears with sound has a robust protective effect against cisplatin-induced hearing loss and hair cell death. Sound therapy also provided protection against aminoglycoside-induced hearing loss. These data indicate that sound preconditioning protects against both classes of ototoxic drugs, and they suggest that sound therapy holds promise for preventing hearing loss in patients receiving these drugs.
Soumen Roy, Matthew M. Ryals, Astrid Botty Van den Bruele, Tracy S. Fitzgerald, Lisa L. Cunningham
Ischemic stroke is a devastating condition, for which there is still no effective therapy. Acute ischemic stroke is associated with high concentrations of glutamate in the blood and interstitial brain fluid. The inability of the tissue to retain glutamate within the cells of the brain ultimately provokes neuronal death. Increased concentrations of interstitial glutamate exert further excitotoxic effects on healthy tissue surrounding the infarct zone. We developed a strategy based on peritoneal dialysis to reduce blood glutamate levels, thereby accelerating brain-to-blood glutamate clearance. In a rat model of stroke, this simple procedure reduced the transient increase in glutamate, consequently decreasing the size of the infarct area. Functional magnetic resonance imaging demonstrated that the rescued brain tissue remained functional. Moreover, in patients with kidney failure, peritoneal dialysis significantly decreased glutamate concentrations. Our results suggest that peritoneal dialysis may represent a simple and effective intervention for human stroke patients.
María del Carmen Godino, Victor G. Romera, José Antonio Sánchez-Tomero, Jesus Pacheco, Santiago Canals, Juan Lerma, José Vivancos, María Angeles Moro, Magdalena Torres, Ignacio Lizasoain, José Sánchez-Prieto
Recent studies described the experimental adaptation of influenza H5 HAs that confers respiratory droplet transmission (rdt) to influenza virus in ferrets. Acquisition of the ability to transmit via aerosol may lead to the development of a highly pathogenic pandemic H5 virus. Vaccines are predicted to play an important role in H5N1 control should the virus become readily transmissible between humans. We obtained PBMCs from patients who received an A/Vietnam/1203/2004 H5N1 subunit vaccine. Human hybridomas were then generated and characterized. We identified antibodies that bound the HA head domain and recognized both WT and rdt H5 HAs. We used a combination of structural techniques to define a mechanism of antibody recognition of an H5 HA receptor–binding site that neutralized H5N1 influenza viruses and pseudoviruses carrying the HA rdt variants that have mutations near the receptor-binding site. Incorporation or retention of this critical antigenic site should be considered in the design of novel H5 HA immunogens to protect against mammalian-adapted H5N1 mutants.
Natalie J. Thornburg, David P. Nannemann, David L. Blum, Jessica A. Belser, Terrence M. Tumpey, Shyam Deshpande, Gloria A. Fritz, Gopal Sapparapu, Jens C. Krause, Jeong Hyun Lee, Andrew B. Ward, David E. Lee, Sheng Li, Katie L. Winarski, Benjamin W. Spiller, Jens Meiler, James E. Crowe Jr.
Tumor cells with donor genotype have been identified in human skin cancer after allogeneic transplantation; however, the donor contribution to the malignant epithelium has not been established. Kidney transplant recipients have an increased risk of invasive skin squamous cell carcinoma (SCC), which is associated with accumulation of the tumor suppressor p53 and
Laurence Verneuil, Mariana Varna, Philippe Ratajczak, Christophe Leboeuf, Louis-François Plassa, Morad Elbouchtaoui, Pierre Schneider, Wissam Sandid, Celeste Lebbé, Marie-Noelle Peraldi, François Sigaux, Hugues de Thé, Anne Janin
Chronic granulomatous disease (CGD) patients have recurrent life-threatening bacterial and fungal infections. Olfactomedin 4 (OLFM4) is a neutrophil granule protein that negatively regulates host defense against bacterial infection. The goal of this study was to evaluate the impact of
Wenli Liu, Ming Yan, Janyce A. Sugui, Hongzhen Li, Chengfu Xu, Jungsoo Joo, Kyung J. Kwon-Chung, William G. Coleman, Griffin P. Rodgers
Diabetes elevates the risk for neurological diseases, but little is known about the underlying mechanisms. Brain-derived neurotrophic factor (BDNF) is secreted by microvascular endothelial cells (ECs) in the brain, functioning as a neuroprotectant through the activation of the neurotrophic tyrosine kinase receptor TRKB. In a rat model of streptozotocin-induced hyperglycemia, we found that endothelial activation of MMP9 altered TRKB-dependent trophic pathways by degrading TRKB in neurons. Treatment of brain microvascular ECs with advanced glycation endproducts (AGE), a metabolite commonly elevated in diabetic patients, increased MMP9 activation, similar to in vivo findings. Recombinant human MMP9 degraded the TRKB ectodomain in primary neuronal cultures, suggesting that TRKB could be a substrate for MMP9 proteolysis. Consequently, AGE-conditioned endothelial media with elevated MMP9 activity degraded the TRKB ectodomain and simultaneously disrupted the ability of endothelium to protect neurons against hypoxic injury. Our findings demonstrate that neuronal TRKB trophic function is ablated by MMP9-mediated degradation in the diabetic brain, disrupting cerebrovascular trophic coupling and leaving the brain vulnerable to injury.
Deepti Navaratna, Xiang Fan, Wendy Leung, Josephine Lok, Shuzhen Guo, Changhong Xing, Xiaoying Wang, Eng H. Lo
Brown adipose tissue (BAT) burns fat to produce heat when the body is exposed to cold and plays a role in energy metabolism. Using fluorodeoxyglucose-positron emission tomography and computed tomography, we previously reported that BAT decreases with age and thereby accelerates age-related accumulation of body fat in humans. Thus, the recruitment of BAT may be effective for body fat reduction. In this study, we examined the effects of repeated stimulation by cold and capsinoids (nonpungent capsaicin analogs) in healthy human subjects with low BAT activity. Acute cold exposure at 19°C for 2 hours increased energy expenditure (EE). Cold-induced increments of EE (CIT) strongly correlated with BAT activity independently of age and fat-free mass. Daily 2-hour cold exposure at 17°C for 6 weeks resulted in a parallel increase in BAT activity and CIT and a concomitant decrease in body fat mass. Changes in BAT activity and body fat mass were negatively correlated. Similarly, daily ingestion of capsinoids for 6 weeks increased CIT. These results demonstrate that human BAT can be recruited even in individuals with decreased BAT activity, thereby contributing to body fat reduction.
Takeshi Yoneshiro, Sayuri Aita, Mami Matsushita, Takashi Kayahara, Toshimitsu Kameya, Yuko Kawai, Toshihiko Iwanaga, Masayuki Saito
Numerous common genetic variants have been linked to blood pressure, but no underlying mechanism has been elucidated. Population studies have revealed that the variant rs5068 (A/G) in the 3′ untranslated region of
Pankaj Arora, Connie Wu, Abigail May Khan, Donald B. Bloch, Brandi N. Davis-Dusenbery, Anahita Ghorbani, Ester Spagnolli, Andrew Martinez, Allicia Ryan, Laurel T. Tainsh, Samuel Kim, Jian Rong, Tianxiao Huan, Jane E. Freedman, Daniel Levy, Karen K. Miller, Akiko Hata, Federica del Monte, Sara Vandenwijngaert, Melissa Swinnen, Stefan Janssens, Tara M. Holmes, Emmanuel S. Buys, Kenneth D. Bloch, Christopher Newton-Cheh, Thomas J. Wang
Amélie Bonnefond, Anne Raimondo, Fanny Stutzmann, Maya Ghoussaini, Shwetha Ramachandrappa, David C. Bersten, Emmanuelle Durand, Vincent Vatin, Beverley Balkau, Olivier Lantieri, Violeta Raverdy, François Pattou, Wim Van Hul, Luc Van Gaal, Daniel J. Peet, Jacques Weill, Jennifer L. Miller, Fritz Horber, Anthony P. Goldstone, Daniel J. Driscoll, John B. Bruning, David Meyre, Murray L. Whitelaw, Philippe Froguel
Adenoid cystic carcinoma (ACC) is a rare malignancy that can occur in multiple organ sites and is primarily found in the salivary gland. While the identification of recurrent fusions of the
Philip J. Stephens, Helen R. Davies, Yoshitsugu Mitani, Peter Van Loo, Adam Shlien, Patrick S. Tarpey, Elli Papaemmanuil, Angela Cheverton, Graham R. Bignell, Adam P. Butler, John Gamble, Stephen Gamble, Claire Hardy, Jonathan Hinton, Mingming Jia, Alagu Jayakumar, David Jones, Calli Latimer, Stuart McLaren, David J. McBride, Andrew Menzies, Laura Mudie, Mark Maddison, Keiran Raine, Serena Nik-Zainal, Sarah O’Meara, Jon W. Teague, Ignacio Varela, David C. Wedge, Ian Whitmore, Scott M. Lippman, Ultan McDermott, Michael R. Stratton, Peter J. Campbell, Adel K. El-Naggar, P. Andrew Futreal
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