RESUMEN
In Parkinson's disease (PD), progressive degeneration of nigrostriatal innervation leads to atrophy and loss of dendritic spines of striatal medium spiny neurons (MSNs). The loss disrupts corticostriatal transmission, impairs motor behavior, and produces nonmotor symptoms. Nigral neurons express brain-derived neurotropic factor (BDNF) and dopamine D3 receptors, both protecting the dopamine neurons and the spines of MSNs. To restore motor and nonmotor symptoms to normality, we assessed a combined therapy in a bilateral rat Parkinson's model, with only 30% of surviving neurons. The preferential D3 agonist pramipexole (PPX) was infused for four ½ months via mini-osmotic pumps and one month after PPX initiation; the BDNF-gene was transfected into the surviving nigral cells using the nonviral transfection NTS-polyplex vector. Overexpression of the BDNF-gene associated with continuous PPX infusion restored motor coordination, balance, normal gait, and working memory. Recovery was also related to the restoration of the average number of dendritic spines of the striatal projection neurons and the number of TH-positive neurons of the substantia nigra and ventral tegmental area. These positive results could pave the way for further clinical research into this promising therapy.
RESUMEN
Cytotoxic cellular responses are crucial for clearing intracellular pathogens and generating host resistance. Experimental pulmonary tuberculosis is associated with an early delay in T cell responses and with elevated lung bacterial burden during chronic infection. In this study we quantified the in vivo cytotoxicity and the mycobacterial burden from two pertinent tissues in groups of mice infected each with a mycobacterial strain of different virulence. None of the strains induced cytotoxic responses during early (day 14) infection. Interestingly, at 21 and 60 days post-infection, Mycobacterium canettii (lowest virulence) triggered the strongest in vivo cytotoxicity both in lungs and mediastinal lymph nodes. In contrast, Mycobacterium tuberculosis H37Rv (intermediate virulence) and Beijing strains (highest virulence) induced lower cytotoxic responses, and exhibited high bacterial growth, especially in lungs. These in vivo data suggest that virulence of Mycobacterium strains are somehow associated with subverting cytotoxic responses, thus contributing to early bacterial replication and subsequent persistence in the lungs.
Asunto(s)
Pulmón/patología , Ganglios Linfáticos/patología , Mycobacterium tuberculosis/inmunología , Neumonía/inmunología , Tuberculosis/inmunología , Animales , Citotoxicidad Inmunológica , Modelos Animales de Enfermedad , Humanos , Pulmón/inmunología , Pulmón/microbiología , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/microbiología , Masculino , Ratones , Ratones Endogámicos BALB C , Mycobacterium tuberculosis/crecimiento & desarrollo , Mycobacterium tuberculosis/patogenicidad , Neumonía/microbiología , Especificidad de la Especie , Linfocitos T/inmunología , Tuberculosis/microbiología , Virulencia/inmunologíaRESUMEN
Hypoxia, a driver of tumor growth and metastasis, regulates angiogenic pathways that are targets for vessel normalization and ovarian cancer management. However, toxicities and resistance to anti-angiogenics can limit their use making identification of new targets vital. Inhibin, a heteromeric TGFß ligand, is a contextual regulator of tumor progression acting as an early tumor suppressor, yet also an established biomarker for ovarian cancers. Here, we find that hypoxia increases inhibin levels in ovarian cancer cell lines, xenograft tumors, and patients. Inhibin is regulated primarily through HIF-1, shifting the balance under hypoxia from activins to inhibins. Hypoxia regulated inhibin promotes tumor growth, endothelial cell invasion and permeability. Targeting inhibin in vivo through knockdown and anti-inhibin strategies robustly reduces permeability in vivo and alters the balance of pro and anti-angiogenic mechanisms resulting in vascular normalization. Mechanistically, inhibin regulates permeability by increasing VE-cadherin internalization via ACVRL1 and CD105, a receptor complex that we find to be stabilized directly by inhibin. Our findings demonstrate direct roles for inhibins in vascular normalization via TGF-ß receptors providing new insights into the therapeutic significance of inhibins as a strategy to normalize the tumor vasculature in ovarian cancer.