Mounting attention has been focused on defects in macroautophagy/autophagy and the autophagylysosomal pathway (ALP) in cerebral ischemia. TFEB (transcription factor EB)-mediated induction of ALP has been recently considered as the common mechanism in ameliorating the pathological lesion of myocardial ischemia and neurodegenerative diseases. Here we explored the vital role of TFEB in permanent middle cerebral artery occlusion (pMCAO)-mediated dysfunction of ALP and ischemic insult in rats. The results showed that ALP function was first enhanced in the early stage of the ischemic process, especially in neurons of the cortex, and this was accompanied by increased TFEB expression and translocation to the nucleus, which was mediated at least in part through activation by PPP3/ calcineurin. At the later stages of ischemia, a gradual decrease in the level of nuclear TFEB was coupled with a progressive decline in lysosomal activity, accumulation of autophagosomes and autophagy substrates, and exacerbation of the ischemic injury. Notably, neuron-specific overexpression of TFEB significantly enhanced ALP function and rescued the ischemic damage, starting as early as 6 h and even lasting to 48 h after ischemia. Furthermore, neuron-specific knockdown of TFEB markedly reversed the activation of ALP and further aggravated the neurological deficits and ischemic outcome at the early stage of pMCAO. These results highlight neuronal-targeted TFEB as one of the key players in the pMCAO-mediated dysfunction of ALP and ischemic injury, and identify TFEB as a promising target for therapies aimed at neuroprotection in cerebral ischemia.
Abstract. Primary renal lymphoma (PRL) is a rare disease, with no more than 70 cases reported in the literature. The present study reports the case of a 70-year-old woman with PRL. The patient was asymptomatic, however, a mass on the right kidney was identified incidentally during routine physical examination. Computed tomography revealed a mass in the right kidney that was 3.6 cm in diameter. Subsequently, right nephrectomy was performed. The histological evaluation of the nephrectomy specimen showed diffuse large B-cell non-Hodgkin's lymphoma. The patient was treated with 6-8 cycles of a cyclophosphamide, epirubicin, vindesine and dexamethasone regimen. Follow-up examination performed after 2 months of treatment revealed no evidence of local recurrence. The present study also reviewed 49 cases of PRL that have been reported since 1989. It was found that a shorter survival time was experienced by patients with bilateral PRL (mean, 21 months) compared with unilateral PRL (mean, 68 months). A shorter survival time was also experienced by patients who were treated with chemotherapy only (mean, 15.8 months) compared with those who were treated with combination chemotherapy and surgery (mean, 49.4 months).
Background: Microglial activation is a prominent feature of neuroinflammation, which is present in almost all neurodegenerative diseases. While an initial inflammatory response mediated by microglia is considered to be protective, excessive pro-inflammatory response of microglia contributes to the pathogenesis of neurodegeneration. Although autophagy is involved in the suppression of inflammation, its role and mechanism in microglia are unclear. Methods: In the present study, we studied the mechanism by which lipopolysaccharide (LPS) affects microglial autophagy and the effects of autophagy on the production of pro-inflammatory factors in microglial cells by western blotting, immunocytochemistry, transfection, transmission electron microscopy (TEM), and real-time PCR. In a mouse model of neuroinflammation, generated by intraventricular injection of LPS (5 μg/animal), we induced autophagy by rapamycin injection and investigated the effects of enhanced autophagy on microglial activation by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry. Results: We found that autophagic flux was suppressed in LPS-stimulated N9 microglial cells, as evidenced by decreased expression of the autophagy marker LC3-II (lipidated form of MAP1LC3), as well as increased levels of the autophagy adaptor protein SQSTM1. LPS significantly decreased Vps34 expression in N9 microglial cells by activating the PI3KI/AKT/MTOR pathway without affecting the levels of lysosome-associated proteins and enzymes. More importantly, overexpression of Vps34 significantly enhanced the autophagic flux and decreased the accumulation of SQSTM1 in LPS-stimulated N9 microglial cells. Moreover, our results revealed that an LPS-induced reduction in the level of Vps34 prevented the maturation of omegasomes to phagophores. Furthermore, LPSinduced neuroinflammation was significantly ameliorated by treatment with the autophagy inducer rapamycin both in vitro and in vivo.
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