Abstract:
Cell-permeant fusion peptides Tat-PDZ can dose-dependently reduce the threshold for anesthesia. PDZ domain-mediated protein interactions at synapses in the central nervous system play an important role in the molecular mechanisms of anesthesia. Moreover, Tat-PDZ cell-permeant fusion peptides are delivered intracellularly into neurons in the central nervous system subsequent to intraperitoneally injection. By in vitro and in vivo binding assays, we found that the Tat-PDZ dose-dependently inhibited the interactions between NMDARs and PSD-95. Furthermore, behavior testing showed that animals given Tat-PDZ exhibited significantly reduced established inflammatory pain behaviors compared to vehicle-treated group. Our results indicate that by disrupting NMDAR/PSD-95 protein interactions, the Tat-PDZ cell-permeable fusion peptides provide a new approach for inflammatory pain therapy.
Abstract:
Cell-permeant fusion peptides Tat-PDZ can dose-dependently reduce the threshold for anesthesia. PDZ domain-mediated protein interactions at synapses in the central nervous system play an important role in the molecular mechanisms of anesthesia. Moreover, Tat-PDZ cell-permeant fusion peptides are delivered intracellularly into neurons in the central nervous system subsequent to intraperitoneally injection. By in vitro and in vivo binding assays, we found that the Tat-PDZ dose-dependently inhibited the interactions between NMDARs and PSD-95. Furthermore, behavior testing showed that animals given Tat-PDZ exhibited significantly reduced established inflammatory pain behaviors compared to vehicle-treated group. Our results indicate that by disrupting NMDAR/PSD-95 protein interactions, the Tat-PDZ cell-permeable fusion peptides provide a new approach for inflammatory pain therapy.
Abstract:
PSD-95/SAP90 antisense-treated animals not only experience a significant decrease in MAC for isoflurane, but also experience an attenuation in the NMDA-induced increase in isoflurane MAC. PSD-95/SAP90 appears to mediate the role of the NMDA receptor in determining the MAC of inhalational anesthetics. Suppression of the expression of PSD-95/SAP90 in the spinal cord significantly attenuates responses to painful stimuli mediated through the N-methyl-D-aspartate receptor activation. In spinal cord neurons PSD-95/SAP90 interacts with the N-methyl-D-aspartate receptor subunits 2A/2B. Activation of the N-methyl-D-aspartate receptor in spinal hyperalgesia results in association of the N-methyl-D-aspartate receptor with PSD-95/SAP90. PSD-95/SAP90 is required for hyperalgesia triggered via the N-methyl-D-aspartate receptor at the spinal cord level.
Abstract:
Hypoxia induced mitogenic factor (HIMF) is a member of the “found in inflammatory zone” (FIZZ)/resistin family of proteins and has potent mitogenic, angiogenic, and vasoconstrictive effects in the lung vasculature. We use antibodies to HIMF to treat certain diseases including adult respiratory distress syndrome, radiation-induced pulmonary fibrosis, idiopathic pulmonary fibrosis, and emphysema.
Abstract:
Several lines of evidence have shown a role for the nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signaling pathway in the development of spinal hyperalgesia. However, the roles of effectors for cGMP are not fully understood in the processing of pain in the spinal cord. cGMP-dependent protein kinase (PKG) I&agr; but not PKGI&bgr; was localized in the neuronal bodies and processes, and was distributed primarily in the superficial laminae of the spinal cord. Intrathecal administration of an inhibitor of PKGI&agr;, Rp-8-[(4-Chlorophenyl)thio]-cGMPS triethylamine, produces significant antinociception. Moreover, PKGI&agr; protein expression was dramatically increased in the lumbar spinal cord after noxious stimulation. This upregulation of PKGI&agr; expression was completely blocked not only by a neuronal NO synthase inhibitor, and a soluble guanylate cyclase inhibitor, but also by an N-methyl-D-aspartate (NMDA) receptor antagonist, MK-801. Noxious stimulation not only initially activates but also later upregulates PKGI&agr; expression in the superficial laminae via an NMDA-NO-cGMP signaling pathway, suggesting that PKGI&agr; plays an important role in the central mechanism of inflammatory hyperalgesia in the spinal cord.
Abstract:
Several lines of evidence have shown a role for the nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signaling pathway in the development of spinal hyperalgesia. However, the roles of effectors for cGMP are not fully understood in the processing of pain in the spinal cord. cGMP-dependent protein kinase (PKG) Iα but not PKGIβ was localized in the neuronal bodies and processes, and was distributed primarily in the superficial laminae of the spinal cord. Intrathecal administration of an inhibitor of PKGIα, Rp-8-[(4-Chlorophenyl)thio]-cGMPS triethylamine, produces significant antinociception. Moreover, PKGIα protein expression was dramatically increased in the lumbar spinal cord after noxious stimulation. This upregulation of PKGIα expression was completely blocked not only by a neuronal NO synthase inhibitor, and a soluble guanylate cyclase inhibitor, but also by an N-methyl-D-aspartate (NMDA) receptor antagonist, MK-801. Noxious stimulation not only initially activates but also later upregulates PKGIα expression in the superficial laminae via an NMDA-No-cGMP signaling pathway, suggesting that PKGIα plays an important role in the central mechanism of inflammatory hyperalgesia in the spinal cord.
Abstract:
PSD-95/SAP90 antisense-treated animals not only experience a significant decrease in MAC for isoflurane, but also experience an attenuation in the NMDA-induced increase in isoflurane MAC. PSD-95/SAP90 appears to mediate the role of the NMDA receptor in determining the MAC of inhalational anesthetics. Suppression of the expression of PSD-95/SAP90 in the spinal cord significantly attenuates responses to painful stimuli mediated through the N-methyl-D-aspartate receptor activation. In spinal cord neurons PSD-95/SAP90 interacts with the N-methyl-D-aspartate receptor subunits 2A/2B. Activation of the N-methyl-D-aspartate receptor in spinal hyperalgesia results in association of the N-methyl-D-aspartate receptor with PSD-95/SAP90. PSD-95/SAP90 is required for hyperalgesia triggered via the N-methyl-D-aspartate receptor at the spinal cord level.
Abstract:
Hypoxia induced mitogenic factor (HIMF) is a member of the “found in inflammatory zone” (FIZZ)/resistin family of proteins and has potent mitogenic, angiogenic, and vasoconstrictive effects in the lung vasculature. The receptor/binding partners for this family of proteins have been largely unknown. We identified Bruton's tyrosine kinase (BTK) as a functional HIMF binding partner through GST-HIMF pull-downs and mass spectrometry. Using primary cultured HIMF-stimulated murine bone marrow cells, we demonstrated that BTK was recruited to the leading edge of the cells. We also demonstrated that BTK and the closely related tyrosine kinase Fyn, colocalized at the growth cone process in these cells. HIMF stimulation induced BTK autophosphorylation, which peaked at 2.5 minutes. A transwell migration assay showed that treatment with recombinant murine HIMF induced migration of primary cultured bone marrow cells, which was completely blocked by the BTK inhibitor, LFM-A13. In vivo studies, using the rat hindlimb ischemia model, revealed that HIMF can stimulate angiogenesis in the hypoxic tissue probably through inducing the migration of endothelial progenitor cells (EPCs) to areas of active angiogenesis. Our results indicate that HIMF may acts as a chemotactic molecule in stimulating the migration of leukocytes/EPCs from bone marrow to targeted tissues through activation of the BTK pathway.
Abstract:
Several lines of evidence have shown a role for the nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signaling pathway in the development of spinal hyperalgesia. However, the roles of effectors for cGMP are not fully understood in the processing of pain in the spinal cord. cGMP-dependent protein kinase (PKG) Iα but not PKGIβ was localized in the neuronal bodies and processes, and was distributed primarily in the superficial laminae of the spinal cord. Intrathecal administration of an inhibitor of PKGIα, Rp-8-[(4-Chlorophenyl)thio]-cGMPS triethylamine, produces significant antinociception. Moreover, PKGIα protein expression was dramatically increased in the lumbar spinal cord after noxious stimulation. This upregulation of PKGIα expression was completely blocked not only by a neuronal NO synthase inhibitor, and a soluble guanylate cyclase inhibitor, but also by an N-methyl-D-aspartate (NMDA) receptor antagonist, MK-801. Noxious stimulation not only initially activates but also later upregulates PKGIα expression in the superficial laminae via an NMDA-NO-cGMP signaling pathway, suggesting that PKGIα plays an important role in the central mechanism of inflammatory hyperalgesia in the spinal cord.