Positional headache refers to a headache that worsens or improves with changes in posture. It is often secondary in nature, associated with various pathologies that may have serious consequences if left undiagnosed or untreated. The authors report a patient who complained of severe positional headache and was diagnosed with concurrent reversible cerebral vasoconstriction syndrome and vertebral artery dissection, thus highlighting the importance of considering such conditions in a patient with postural headaches.

Positional headache refers to a headache that worsens or improves with changes in posture. It is often secondary in nature, associated with various pathologies that may have serious consequences if left undiagnosed or untreated. The authors report a patient who complained of severe positional headache and was diagnosed with concurrent reversible cerebral vasoconstriction syndrome and vertebral artery dissection, thus highlighting the importance of considering such conditions in a patient with postural headaches.

Herpes simplex encephalitis is known to cause intracranial hypertension and cerebral edema. When cerebral edema occurs, venous sinuses are compressed, resulting in congestion and thrombosis. An arteriovenous fistula may form as a result, particularly in conjunction with superior sagittal sinus thrombosis. In this report, the authors describe a patient with protein S and C deficiency who developed venous sinus thrombosis and dural arteriovenous fistula after experiencing herpes simplex encephalitis.

Positional headache refers to a headache that worsens or improves with changes in posture. It is often secondary in nature, associated with various pathologies that may have serious consequences if left undiagnosed or untreated. The authors report a patient who complained of severe positional headache and was diagnosed with concurrent reversible cerebral vasoconstriction syndrome and vertebral artery dissection, thus highlighting the importance of considering such conditions in a patient with postural headaches.

Positional headache refers to a headache that worsens or improves with changes in posture. It is often secondary in nature, associated with various pathologies that may have serious consequences if left undiagnosed or untreated. The authors report a patient who complained of severe positional headache and was diagnosed with concurrent reversible cerebral vasoconstriction syndrome and vertebral artery dissection, thus highlighting the importance of considering such conditions in a patient with postural headaches.

Excessive immune responses induced by ischemia-reperfusion injury (IRI) are known to lead to necrotic and apoptotic cell death, and calcineurin plays a major role in this process. Calcineurin dephosphorylates the nuclear factor of activated T-cells (NFAT), permitting its translocation into the nucleus. As a result, calcineurin promotes the release of pro-inflammatory cytokines, such as tumor necrosis factor-alpha. The overproduction of pro-inflammatory cytokines causes renal cell death. Calcineurin activity is regulated by calpain, a cysteine protease present in the nucleus. Calpain-mediated proteolysis increases the phosphatase activity of calcineurin, resulting in NFAT dephosphorylation. This process has been studied in cardiomyocytes but its role in renal IRI is unknown. Thus, we examined whether calpain regulates calcineurin in renal tubule nuclei. We established an in vivo renal IRI model in mice and identified the protective role of a calcineurin inhibitor, FK506, in this process. Calcineurin is expressed in the nucleus, where it is present in its calpain-cleaved form. FK506 reduced nuclear expression of calcineurin and prevented calcineurin-mediated NFAT activation. Our study shows clearly that FK506 reduces calpain-mediated calcineurin activity. Consequently, calcineurin could not maintain NFAT activation. FK506 reduced renal cell death by suppressing the transcription of pro-inflammatory cytokine genes. This study provides evidence that FK506 protects against inflammation in a renal IRI mouse model. We also provided a mechanism of calcineurin action in the nucleus. Therefore, FK506 could improve renal function by decreasing calcineurin activity in both the cytoplasm and the nucleus of renal tubule cells.
Animals ; Calcineurin* ; Calpain ; Cell Death ; Cysteine Proteases ; Cytokines ; Cytoplasm* ; Inflammation ; Mice ; Myocytes, Cardiac ; Proteolysis ; Reperfusion Injury ; T-Lymphocytes ; Tacrolimus* ; Tumor Necrosis Factor-alpha

Excessive immune responses induced by ischemia-reperfusion injury (IRI) are known to lead to necrotic and apoptotic cell death, and calcineurin plays a major role in this process. Calcineurin dephosphorylates the nuclear factor of activated T-cells (NFAT), permitting its translocation into the nucleus. As a result, calcineurin promotes the release of pro-inflammatory cytokines, such as tumor necrosis factor-alpha. The overproduction of pro-inflammatory cytokines causes renal cell death. Calcineurin activity is regulated by calpain, a cysteine protease present in the nucleus. Calpain-mediated proteolysis increases the phosphatase activity of calcineurin, resulting in NFAT dephosphorylation. This process has been studied in cardiomyocytes but its role in renal IRI is unknown. Thus, we examined whether calpain regulates calcineurin in renal tubule nuclei. We established an in vivo renal IRI model in mice and identified the protective role of a calcineurin inhibitor, FK506, in this process. Calcineurin is expressed in the nucleus, where it is present in its calpain-cleaved form. FK506 reduced nuclear expression of calcineurin and prevented calcineurin-mediated NFAT activation. Our study shows clearly that FK506 reduces calpain-mediated calcineurin activity. Consequently, calcineurin could not maintain NFAT activation. FK506 reduced renal cell death by suppressing the transcription of pro-inflammatory cytokine genes. This study provides evidence that FK506 protects against inflammation in a renal IRI mouse model. We also provided a mechanism of calcineurin action in the nucleus. Therefore, FK506 could improve renal function by decreasing calcineurin activity in both the cytoplasm and the nucleus of renal tubule cells.
Animals ; Calcineurin* ; Calpain ; Cell Death ; Cysteine Proteases ; Cytokines ; Cytoplasm* ; Inflammation ; Mice ; Myocytes, Cardiac ; Proteolysis ; Reperfusion Injury ; T-Lymphocytes ; Tacrolimus* ; Tumor Necrosis Factor-alpha

Sirtuin 1 (SIRT1) is a mammalian NAD+-dependent protein deacetylase that regulates cellular metabolism and inflammatory response. The organ-specific deletion of SIRT1 induces local inflammation and insulin resistance in dietary and genetic obesity. Macrophage-mediated inflammation contributes to insulin resistance and metabolic syndrome, however, the macrophage-specific SIRT1 function in the context of obesity is largely unknown. C57/BL6 wild type (WT) or myeloid-specific SIRT1 knockout (KO) mice were fed a high-fat diet (HFD) or normal diet (ND) for 12 weeks. Metabolic parameters and markers of hepatic steatosis and inflammation in liver were compared in WT and KO mice. SIRT1 deletion enhanced HFD-induced changes on body and liver weight gain, and increased glucose and insulin resistance. In liver, SIRT1 deletion increased the acetylation, and enhanced HFD-induced nuclear translocation of nuclear factor kappa B (NF-kappaB), hepatic inflammation and macrophage infiltration. HFD-fed KO mice showed severe hepatic steatosis by activating lipogenic pathway through sterol regulatory element-binding protein 1 (SREBP-1), and hepatic fibrogenesis, as indicated by induction of connective tissue growth factor (CTGF), alpha-smooth muscle actin (alpha-SMA), and collagen secretion. Myeloid-specific deletion of SIRT1 stimulates obesity-induced inflammation and increases the risk of hepatic fibrosis. Targeted induction of macrophage SIRT1 may be a good therapy for alleviating inflammation-associated metabolic syndrome.
Acetylation ; Actins ; Animals ; Collagen ; Connective Tissue Growth Factor ; Diet ; Diet, High-Fat ; Fibrosis ; Glucose ; Inflammation* ; Insulin Resistance ; Liver ; Macrophages ; Metabolism ; Mice* ; NF-kappa B ; Obesity ; Sirtuin 1 ; Sterol Regulatory Element Binding Protein 1 ; Weight Gain