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Aging is considered to be accelerated by insulin signaling in lower organisms, but it remained unclear whether this could hold true for mammals. Here we show that mice with skeletal muscle-specific double knockout of Akt1/2, key downstream molecules of insulin signaling, serve as a model of premature sarcopenia with insulin resistance. The knockout mice exhibit a progressive reduction in skeletal muscle mass, impairment of motor function and systemic insulin sensitivity. They also show osteopenia, and reduced lifespan largely due to death from debilitation on normal chow and death from tumor on high-fat diet. These phenotypes are almost reversed by additional knocking out of Foxo1/4, but only partially by additional knocking out of Tsc2 to activate the mTOR pathway. Overall, our data suggest that, unlike in lower organisms, suppression of Akt activity in skeletal muscle of mammals associated with insulin resistance and aging could accelerate osteosarcopenia and consequently reduce lifespan. Sasako et al. show that disruption of the insulin/IGF-1 signaling by suppressing Akt activity in mouse skeletal muscle can accelerate osteosarcopenia and shortens lifespan, which is reversed by inactivation of FoxOs rather than activation of mTOR, suggesting FoxOs as therapeutic targets. [ABSTRACT FROM AUTHOR]

To clarify the neuroprotective property of ceruloplasmin and the pathogenesis of aceruloplasminemia, we generated ceruloplasmin-deficient ( CP) mice on the C57BL/10 genetic background and further treated them with a mitochondrial complex I inhibitor, rotenone. There was no iron accumulation in the brains of CP mice at least up to 60 weeks of age. Without rotenone treatment, CP mice showed slight motor dysfunction compared with CP mice, but there were no detectable differences in the levels of oxidative stress markers between these two groups. A low dose of rotenone did not affect the mitochondrial complex I activity in our mice, however, it caused a significant change in motor behavior, neuropathology, or the levels of oxidative stress markers in CP mice, but not in CP mice. Our data support that ceruloplasmin protects against rotenone-induced oxidative stress and neurotoxicity, probably through its antioxidant properties independently of its function of iron metabolism. [ABSTRACT FROM AUTHOR]

This report concerns a patient with systemic lupus erythematosus (SLE) who died of acute respiratory distress syndrome (ARDS) 1 day after the onset of pulmonary symptoms. Autopsy demonstrated severe hemophagocytosis in the bone marrow and histopathology indicating a marked increase in vascular permeability in both lungs and kidneys. In this patient, active SLE and associated hemophagocytic syndrome may have induced an increase in the production of inflammatory cytokines, which immediately induced ARDS. Since fatal ARDS can occur as a life-threatening complication of SLE, careful observation is necessary, particularly when there are clinical findings suggestive of associated hemophagocytic syndrome. [ABSTRACT FROM AUTHOR]

We report a young female patient with Henoch–Schönlein purpura (HSP) nephritis complicated by reversible posterior leukoencephalopathy syndrome (RPLS). The patient suddenly showed generalized seizures and cortical blindness with severe hypertension due to renal insufficiency approximately 1 year after cessation of corticosteroid treatment for HSP nephritis. Magnetic resonance imaging (MRI) demonstrated bilateral abnormal signals mainly in the cerebellum and white matter of the occipital lobe. Clinical symptoms quickly improved in conjunction with disappearance of abnormal signals on brain MRI after starting control of hypertension and continuous hemodiafiltration with steroid pulse therapy and plasmapheresis. RPLS may be caused by vasculitis and also by hemodynamic change due to severe hypertension in HSP, particularly in patients with nephropathy. In such cases intensive treatment should be performed as soon as possible to avoid neurological sequelae. [ABSTRACT FROM AUTHOR]