ABSTRACT
The α-Klotho is an anti-aging protein that, when overexpressed, extends the life span in humans and mice. It has an anti-inflammatory and protective action on renal cells by inhibiting NF-κB activation and production of inflammatory cytokines in response to TNF-α. Furthermore, studies have shown the neuroprotective effect of α-Klotho against neuroinflammation on different conditions, such as aging, animal models of neurodegenerative diseases, and ischemic brain injury. This work aimed to evaluate the effects of α-Klotho protein on primary glial cell culture against the proinflammatory challenge with LPS and how this could interfere with neuronal health. Cortical mixed glial cells and purified astrocytes were pretreated with α- α-Klotho and stimulated with LPS followed by TNFα, IL-1ß, IL-6, IFN-γ levels, and NF-κB activity analysis. Conditioned medium from cortical mixed glia culture treated with LPS (glia conditioned medium (GCM) was used to induce neuronal death of primary cortical neuronal culture and evaluate if GCM-KL (medium from glia culture pretreated α-Klotho followed by LPS stimulation) or GCM + LPS in the presence of KL can reverse the effect. LPS treatment in glial cells induced an increase in proinflammatory mediators such as TNF-α, IL-1ß, IL-6, and IFN-γ, and activation of astrocyte NF-κB. GCM treated-cortical neuronal culture induced a concentration-dependent neuronal death. Pretreatment with α-Klotho decreased TNF-α and IL-6 production, reverted NF-κB activation, and decreased neuronal death induced by GCM. In addition, KL incubation together with GCM + LPS completely reverts the neuronal toxicity induced by low concentration of GCM-LPS. These data suggest an anti-inflammatory and neuroprotective effect of α-Klotho protein in the CNS. This work demonstrated the therapeutic potential of α-Klotho in pathological processes which involves a neuroinflammatory component.
Subject(s)
NF-kappa B , Neuroprotective Agents , Humans , Animals , Mice , NF-kappa B/metabolism , Lipopolysaccharides/pharmacology , Lipopolysaccharides/metabolism , Culture Media, Conditioned/pharmacology , Culture Media, Conditioned/metabolism , Tumor Necrosis Factor-alpha/metabolism , Neuroprotective Agents/pharmacology , Neuroprotective Agents/metabolism , Interleukin-6/metabolism , Klotho Proteins , Neuroglia/metabolism , Neurons/metabolism , Anti-Inflammatory Agents/pharmacology , Inflammation/metabolismABSTRACT
Na+ /K+ -ATPase, a transmembrane protein essential for maintaining the electrochemical gradient across the plasma membrane, acts as a receptor for cardiotonic steroids such as ouabain. Cardiotonic steroids binding to Na+ /K+ -ATPase triggers signalling pathways or inhibits Na+ /K+ -ATPas activity in a concentration-dependent manner, resulting in a modulation of Ca2+ levels, which are essential for homeostasis in neurons. However, most of the pharmacological strategies for avoiding neuronal death do not target Na+ /K+ -ATPase activity due to its complexity and the poor understanding of the mechanisms involved in Na+ /K+ -ATPase modulation. The present review aims to discuss two points regarding the interplay between Na+ /K+ -ATPase and Ca2+ signalling in the brain. One, Na+ /K+ -ATPase impairment causing illness and neuronal death due to Ca2+ signalling and two, benefits to the brain by modulating Na+ /K+ -ATPase activity. These interactions play an essential role in neuronal cell fate determination and are relevant to find new targets for the treatment of neurodegenerative diseases. LINKED ARTICLES: This article is part of a themed issue on Building Bridges in Neuropharmacology. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.8/issuetoc.
