Akt/Nrf2 Activated Upregulation of Heme Oxygenase-1 Involves in the Role of Rg1 Against Ferrous Iron-Induced Neurotoxicity in SK-N-SH Cells

The liver is a key player for maintaining glucose homeostasis. Excessive hepatic glucose production is considered to be a key for the onset of type 2 diabetes mellitus. The primary function of heme oxygenase-1 (HO1) is to catalyze the degradation of heme into biliverdin, ferrous iron, and carbon monoxide. Previous studies have demonstrated that the degradation of heme by HO1 in the liver results in mitochondrial dysfunction and drives insulin resistance. In this study, by overexpressing HO1 in hepatocytes and mice, we showed that HO1 promotes gluconeogenesis in a Foxo1-dependent manner. Importantly, HO1 overexpression increased the generation of ferrous iron in the liver, which further activates NF-<a>κB</a> and phosphorylates Foxo1 at Ser273 to enhance gluconeogenesis. We further assessed the role of HO1 in insulin-resistant L-DKO (liver-specific knockout of IRS1 and IRS2 genes) mice, which exhibit upregulation of HO1 in the liver and hepatic ferrous iron overload. HO1 knockdown by shRNA or treatment of iron chelator rescued the aberrant gluconeogenesis in L-DKO mice. In addition, we found that systemic iron overload promotes gluconeogenesis by activating hepatic PKA→Foxo1 axis. Thus, our results demonstrate the role of HO1 in regulating hepatic iron status and Foxo1 to control gluconeogenesis and blood glucose.

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Heme Oxygenase-1 Regulates Ferrous Iron and Foxo1 in Control of Hepatic Gluconeogenesis

10.2337/figshare.13382714.v1 ◽

2021 ◽

Author(s):

Ada Admin ◽

Wang Liao ◽

Wanbao Yang ◽

Zheng Shen ◽

Weiqi Ai ◽

...

Keyword(s):

Iron Overload ◽

Heme Oxygenase ◽

Ferrous Iron ◽

Iron Status ◽

Hepatic Glucose Production ◽

Glucose Production ◽

Iron Chelator ◽

Heme Oxygenase 1 ◽

Dependent Manner

The liver is a key player for maintaining glucose homeostasis. Excessive hepatic glucose production is considered to be a key for the onset of type 2 diabetes mellitus. The primary function of heme oxygenase-1 (HO1) is to catalyze the degradation of heme into biliverdin, ferrous iron, and carbon monoxide. Previous studies have demonstrated that the degradation of heme by HO1 in the liver results in mitochondrial dysfunction and drives insulin resistance. In this study, by overexpressing HO1 in hepatocytes and mice, we showed that HO1 promotes gluconeogenesis in a Foxo1-dependent manner. Importantly, HO1 overexpression increased the generation of ferrous iron in the liver, which further activates NF-<a>κB</a> and phosphorylates Foxo1 at Ser273 to enhance gluconeogenesis. We further assessed the role of HO1 in insulin-resistant L-DKO (liver-specific knockout of IRS1 and IRS2 genes) mice, which exhibit upregulation of HO1 in the liver and hepatic ferrous iron overload. HO1 knockdown by shRNA or treatment of iron chelator rescued the aberrant gluconeogenesis in L-DKO mice. In addition, we found that systemic iron overload promotes gluconeogenesis by activating hepatic PKA→Foxo1 axis. Thus, our results demonstrate the role of HO1 in regulating hepatic iron status and Foxo1 to control gluconeogenesis and blood glucose.

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Protective role of heme oxygenase-1 in liver

Biologia ◽

10.2478/s11756-012-0058-1 ◽

2012 ◽

Vol 67 (4) ◽

Cited By ~ 3

Author(s):

Maher Abdalla ◽

Mary Mathahs ◽

Iman Ahmad

Keyword(s):

Oxidative Stress ◽

Heme Oxygenase ◽

Ferrous Iron ◽

Protective Role ◽

Heme Oxygenase 1 ◽

Multiple Forms ◽

Growing Body ◽

Rate Limiting ◽

Transcriptional Induction

AbstractHeme oxygenase-1 (HO-1) is the rate limiting enzyme in heme catabolism and degrades heme to carbon monoxide, biliverdin, and ferrous iron. HO-1 transcriptional induction occurs in response to multiple forms of chemical, physical stress and cytokines. HO-1 confers cytoprotection by inhibiting apoptosis, oxidative stress, and inflammation. Hepatitis C virus (HCV) is a major cause of cirrhosis and hepatocellular carcinoma. It has been shown that HO-1 induction and HO-1 products interfere with replication of HCV and markedly decreased HCV replication. However, a growing body of evidence indicates that induction of HO-1 may be involved in carcinogenesis and can play a role in the metastasis and growth of tumors. The antioxidant, antiviral activity of HO-1 makes it the cytoprotective enzyme for liver tissue in HCV infection, and induction of HO-1 can be suggested as a future therapeutic approach. However, the role of HO-1 in tumor growth should not be ignored.

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Involvement of Heme Oxygenase-1 in Neuropsychiatric and Neurodegenerative Diseases

Current Pharmaceutical Design ◽

10.2174/1381612824666180717160623 ◽

2018 ◽

Vol 24 (20) ◽

pp. 2283-2302 ◽

Cited By ~ 9

Author(s):

Vivian B. Neis ◽

Priscila B. Rosa ◽

Morgana Moretti ◽

Ana Lucia S. Rodrigues

Keyword(s):

Neurodegenerative Diseases ◽

Heme Oxygenase ◽

Therapeutic Potential ◽

Redox Homeostasis ◽

Antioxidant Defenses ◽

Heme Oxygenase 1 ◽

Physiological Conditions ◽

And Oxidative Stress ◽

Defensive Mechanism

Heme oxygenase (HO) family catalyzes the conversion of heme into free iron, carbon monoxide and biliverdin. It possesses two well-characterized isoforms: HO-1 and HO-2. Under brain physiological conditions, the expression of HO-2 is constitutive, abundant and ubiquitous, whereas HO-1 mRNA and protein are restricted to small populations of neurons and neuroglia. HO-1 is an inducible enzyme that has been shown to participate as an essential defensive mechanism for neurons exposed to oxidant challenges, being related to antioxidant defenses in certain neuropathological conditions. Considering that neurodegenerative diseases (Alzheimer’s Disease (AD), Parkinson’s Disease (PD) and Multiple Sclerosis (MS)) and neuropsychiatric disorders (depression, anxiety, Bipolar Disorder (BD) and schizophrenia) are associated with increased inflammatory markers, impaired redox homeostasis and oxidative stress, conditions that may be associated with alterations in HO-levels/activity, the purpose of this review is to present evidence on the possible role of HO-1 in these Central Nervous System (CNS) diseases. In addition, the possible therapeutic potential of targeting brain HO-1 is explored in this review.

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