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Neural stem cells (NSCs) are primary progenitor cells in the early developmental stage in the brain that initiate a diverse lineage of differentiated neurons and glia. Radial glial cells (RGCs), a type of neural stem cell in the ventricular zone, are essential for nurturing and delivering new immature neurons to the appropriate cortical target layers. Here we report that Anoctamin 1 (ANO1)/TMEM16A, a Ca2+-activated chloride channel, mediates the Ca2+-dependent process extension of RGCs. ANO1 is highly expressed and functionally active in RGCs of the mouse embryonic ventricular zone. Knockdown of ANO1 suppresses RGC process extension and protrusions, whereas ANO1 overexpression stimulates process extension. Among various trophic factors, brain-derived neurotrophic factor (BDNF) activates ANO1, which is required for BDNF-induced process extension in RGCs. More importantly, Ano1-deficient mice exhibited disrupted cortical layers and reduced cortical thickness. We thus conclude that the regulation of RGC process extension by ANO1 contributes to the normal formation of mouse embryonic brain. [ABSTRACT FROM AUTHOR]

Benign prostatic hyperplasia (BPH) is characterized by an enlargement of the prostate, causing lower urinary tract symptoms in elderly men worldwide. However, the molecular mechanism underlying the pathogenesis of BPH is unclear. Anoctamin1 (ANO1) encodes a Ca2+-activated chloride channel (CaCC) that mediates various physiological functions. Here, we demonstrate that it is essential for testosterone-induced BPH. ANO1 was highly amplified in dihydrotestosterone (DHT)-treated prostate epithelial cells, whereas the selective knockdown of ANO1 inhibited DHT-induced cell proliferation. Three androgen-response elements were found in the ANO1 promoter region, which is relevant for the DHT-dependent induction of ANO1. Administration of the ANO1 blocker or Ano1 small interfering RNA, inhibited prostate enlargement and reduced histological abnormalities in vivo. We therefore concluded that ANO1 is essential for the development of prostate hyperplasia and is a potential target for the treatment of BPH. [ABSTRACT FROM AUTHOR]

Background The various pathological conditions such as inflammation or injury can evoke pain hypersensitivity. That represents the response to innocuous stimuli or exaggerated response to noxious stimuli. The molecular mechanism based on the pain hypersensitivity is associated with changes in many of the channels in dorsal-root ganglion (DRG) neurons. Anoctamin 1 (ANO1/TMEM16A), a Ca2+ activated chloride channel is highly visible in small DRG neurons and responds to heat. Mice with an abolished function of ANO1 in DRG neurons demonstrated attenuated pain-like behaviors when exposed to noxious heat, suggesting a role in acute thermal nociception. In this study, we further examined the function of ANO1 in mediating inflammation- or injury-induced hyperalgesia or allodynia. Results Using Advillin/Ano1fl/fl (Adv/Ano1fl/fl) mice that have a functional ablation of Ano1 mainly in DRG neurons, we were able to determine its role in mediating thermal hyperalgesia and mechanical allodynia induced by inflammation or nerve injury. The thermal hyperalgesia and mechanical allodynia induced by carrageenan injection and spared-nerve injury were significantly reduced in Adv/Ano1fl/fl mice. In addition, flinching or licking behavior after bradykinin or formalin injection was also significantly reduced in Adv/Ano1fl/fl mice. Since pathological conditions augment nociceptive behaviors, we expected ANO1's contribution to the excitability of DRG neurons. Indeed, the application of inflammatory mediators reduced the threshold for action potential (rheobase) or time for induction of the first potential action in DRG neurons isolated from controlled (Ano1fl/fl) mice. These parameters for neuronal excitability induced by inflammatory mediators were not changed in Adv/Ano1fl/fl mice, suggesting an active contribution of ANO1 in augmenting the neuronal excitability. Conclusions In addition to ANO's role in mediating acute thermal pain as a heat sensor, ANO1 is also capable of augmenting the excitability of DRG neurons under inflammatory or neuropathic conditions and thereby aggravates inflammation- or tissue injury-induced pathological pain. [ABSTRACT FROM AUTHOR]

Background: The quantification of pain intensity in vivo is essential for identifying the mechanisms of various types of pain or for evaluating the effects of different analgesics. A variety of behavioral tests for pain measurement have been devised, but many are limited because animals are physically restricted, which affects pain sensation. In this study, pain assessment was attempted with minimal physical restriction, and voluntary movements of unrestrained animals were used to evaluate the intensities of various types of pain. Results: The number of times animals reared or total distances traveled was measured using a motion-tracking device and found to be markedly reduced in carrageenan-induced inflammatory, acetic acid-induced visceral, and streptozotocin-induced neuropathic pain tests. These two voluntary movement parameters were found to be highly correlated with paw withdrawal latency from irradiating heat. In addition, these parameters were markedly reversed by morphine and by non-steroidal anti-inflammatory drugs in inflammatory pain models. These parameters were also useful to detect hypoalgesia in TRPV1-/- mice. Conclusions: These results suggest that parameters of voluntary movement, such as, number of rearing and total distance moved, are effective indicators of pain intensity for many types of pain and that they can be used to evaluate degree of pain perception. [ABSTRACT FROM AUTHOR]

The quarter-pel motion vector accuracy supported by H.264/advanced video coding (AVC) in motion estimation (ME) and compensation (MC) provides high compression efficiency. However, it also increases the computational complexity. While various well-known fast integer-pel ME methods are already available, lack of a good, fast subpel ME method results in problems associated with relatively high computational complexity. This paper presents one way of solving the complexity problem of subpel ME by making adaptive motion vector (MV) accuracy decisions in inter-mode selection. The proposed MV accuracy decision is made using inter-mode selection of a macroblock with two decision criteria. Pixels are classified as stationary (and/or homogeneous) or nonstationary (and/or nonhomogeneous). In order to avoid unnecessary interpolation and processing, a proper subpel ME level is chosen among four different combinations, each of which has a different MV accuracy and number of subpel ME iterations based on the classification. Simulation results using an open source x264 software encoder show that without any noticeable degradation (by -0.07 dB on average), the proposed method reduces total encoding time and subpel ME time, respectively, by 51.78% and by 76.49% on average, as compared to the conventional full-pel pixel search. [ABSTRACT FROM AUTHOR]

Spinal muscular atrophy and hereditary motor and sensory neuropathies are characterized by muscle weakness and atrophy caused by the degenerations of peripheral motor and sensory nerves. Recent advances in genetics have resulted in the identification of missense mutations in TRPV4 in patients with these hereditary neuropathies. Neurodegeneration caused by Ca2+ overload due to the gain-of-function mutation of TRPV4 was suggested as the molecular mechanism for the neuropathies. Despite the importance of TRPV4 mutations in causing neuropathies, the precise role of TRPV4 in the sensory/motor neurons is unknown. Here, we report that TRPV4 mediates neurotrophic factor-derived neuritogenesis in developing peripheral neurons. TRPV4 was found to be highly expressed in sensory and spinal motor neurons in early development as well as in the adult, and the overexpression or chemical activation of TRPV4 was found to promote neuritogenesis in sensory neurons as well as PC12 cells, whereas its knockdown and pharmacologic inhibition had the opposite effect. More importantly, nerve growth factor or cAMP treatment up-regulated the expression of phospholipase A2 and TRPV4. Neurotrophic factor-derived neuritogenesis appears to be regulated by the phospholipase A2-mediated TRPV4 pathway. These findings show that TRPV4 mediates neurotrophic factor-induced neuritogenesis in developing peripheral nerves. Because neurotrophic factors are essential for the maintenance of peripheral nerves, these findings suggest that aberrant TRPV4 activity may lead to some types of pathology of sensory and motor nerves. [ABSTRACT FROM AUTHOR]

Recent clinical trials using ex vivo expanded mesenchymal stromal cells (MSCs) have raised interest in the safety and function of cultured MSCs. Here, to assess the feasibility of using allogenic human umbilical cord blood serum (CBS) for humanized clinical-grade expansion of MSCs, we characterized MSCs expanded in CBS and compared them to MSCs expanded in fetal bovine serum (FBS). MSCs in CBS exhibited a higher preservation of colony-forming cells and an accelerated expansion over serial passages with increased Oct-4 expression compared to those cultured in FBS. Notably, CBS-expanded MSCs exhibited a unique differentiation potential characterized by a shift from adipogenic to osteogenic differentiation. The differentiation shift was associated with enhanced basal and Runx2-mediated transcriptional activation of the osteocalcin promoter, as well as increased accumulation of -catenin and the yes-associated protein (YAP) which was independent of changes in TAZ (transcriptional co-activator with PDZ-binding motif) levels. Interestingly, the phenotypes were reversed when the FBS and CBS media were switched, suggesting the unique stimulatory effects of CBS rather than the selection of heterogeneous MSC subpopulations. The distinct regulatory effects of CBS on MSC included selective activation of platelet-derived growth factor and epidermal growth factor signals in MSCs, but not in FBS. Taken together, these results provide insight into the dynamic regulation of MSCs during ex vivo culture and show that the ex vivo culture of MSCs in allogenic human CBS provides a novel tool for the accelerated expansion of a population of MSCs that exhibit a higher self-renewal and an enhanced osteogenic potential. [ABSTRACT FROM AUTHOR]

Vanilloid receptor 1 (VR1), a capsaicin receptor, is known to play a major role in mediating inflammatory thermal nociception. Although the physiological role and biophysical properties of VR1 are known, the mechanism of its activation by ligands is poorly understood. Here we show that VR1 must be phosphorylated by Ca2+-calmodulin dependent kinase II (CaMKII) before its activation by capsaicin. In contrast, the dephosphorylation of VR1 by calcineurin leads to a desensitization of the receptor. Moreover, point mutations in VR1 at two putative consensus sites for CaMKII failed to elicit capsaicin-sensitive currents and caused a concomitant reduction in VR1 phosphorylation in vivo. Such mutants also lost their high affinity binding with [³H]resiniferatoxin, a potent capsaicin receptor agonist. We conclude that the dynamic balance between the phosphorylation and dephosphorylation of the VR1 channel by CaMKII and caleineurin, respectively, controls the activation/ desensitization states by regulating VR1 binding. Furthermore, because sensitization by protein kinase A and C converge at these sites, phosphorylation stress in the cell appears to control a wide range of excitabilities in response to various adverse stimuli. [ABSTRACT FROM AUTHOR]

Examines the bradykinin-12-lipoxygenase-vanilloid receptor signaling pathway for inflammatory hyperalgesia. Development of therapeutic strategies for the treatment of inflammatory pain; Quantification of the thermal nociception; Production of the endogenous capsaicin receptor agonist.