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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">Front. Neurol.</journal-id>
<journal-title>Frontiers in Neurology</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Front. Neurol.</abbrev-journal-title>
<issn pub-type="epub">1664-2295</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.3389/fneur.2014.00083</article-id>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Neuroscience</subject>
<subj-group>
<subject>Opinion Article</subject>
</subj-group>
</subj-group>
</article-categories>
<title-group>
<article-title>The Correlation between Osteoporosis Occurrences in Both Schizophrenia and Parkinson&#x02019;s Disease</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name><surname>Radaei</surname> <given-names>Fatemeh</given-names></name>
<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
<uri xlink:href="http://frontiersin.org/people/u/110606"/>
</contrib>
<contrib contrib-type="author">
<name><surname>Darvishi</surname> <given-names>Asma</given-names></name>
<xref ref-type="aff" rid="aff2"><sup>2</sup></xref>
<uri xlink:href="http://frontiersin.org/people/u/162985"/>
</contrib>
<contrib contrib-type="author" corresp="yes">
<name><surname>Gharibzadeh</surname> <given-names>Shahriar</given-names></name>
<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
<xref ref-type="corresp" rid="cor1">&#x0002A;</xref>
<uri xlink:href="http://frontiersin.org/people/u/103117"/>
</contrib>
</contrib-group>
<aff id="aff1"><sup>1</sup><institution>Neural and Cognitive Sciences Laboratory, Biomedical Engineering Faculty, Amirkabir University of Technology</institution>, <addr-line>Tehran</addr-line>, <country>Iran</country></aff>
<aff id="aff2"><sup>2</sup><institution>Tehran University of Medical Sciences</institution>, <addr-line>Tehran</addr-line>, <country>Iran</country></aff>
<author-notes>
<fn fn-type="edited-by"><p>Edited by: Jordi Blanch, Hospital Cl&#x000ED;nic de Barcelona, Spain</p></fn>
<fn fn-type="edited-by"><p>Reviewed by: Varun Kesherwani, University of Nebraska Medical Center, USA</p></fn>
<corresp content-type="corresp" id="cor1">&#x0002A;Correspondence: <email>gharibzadeh&#x00040;aut.ac.ir</email></corresp>
<fn fn-type="other" id="fn001"><p>This article was submitted to Neurodegeneration, a section of the journal Frontiers in Neurology.</p></fn>
</author-notes>
<pub-date pub-type="epub">
<day>02</day>
<month>06</month>
<year>2014</year>
</pub-date>
<pub-date pub-type="collection">
<year>2014</year>
</pub-date>
<volume>5</volume>
<elocation-id>83</elocation-id>
<history>
<date date-type="received">
<day>13</day>
<month>02</month>
<year>2014</year>
</date>
<date date-type="accepted">
<day>16</day>
<month>05</month>
<year>2014</year>
</date>
</history>
<permissions>
<copyright-statement>Copyright &#x000A9; 2014 Radaei, Darvishi and Gharibzadeh.</copyright-statement>
<copyright-year>2014</copyright-year>
<license license-type="open-access" xlink:href="http://creativecommons.org/licenses/by/3.0/"><p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.</p></license>
</permissions>
<kwd-group>
<kwd>Parkinson&#x02019;s disease</kwd>
<kwd>schizophrenia</kwd>
<kwd>osteoporosis</kwd>
<kwd>AMPK</kwd>
<kwd>energy metabolism</kwd>
</kwd-group>
<counts>
<fig-count count="0"/>
<table-count count="0"/>
<equation-count count="0"/>
<ref-count count="14"/>
<page-count count="1"/>
<word-count count="829"/>
</counts>
</article-meta>
</front>
<body>
<p>Osteoporosis disease is a metabolic disorder in which bone mineral density (BMD) is lower than the normal threshold. Based on literature, it is known that schizophrenic patients due to consuming anti-psychotic drugs and Parkinson&#x02019;s disease patients due to vitamin D deficiency and decrease in mobility are at the high risk of osteoporosis (<xref ref-type="bibr" rid="B1">1</xref>&#x02013;<xref ref-type="bibr" rid="B4">4</xref>).</p>
<p>On the other hand, it is observed that adenosine 5&#x02032;-monophosphate (AMP)-activated protein kinase (AMPK) activity, which is regulating cellular energy homeostasis, is reduced in schizophrenia diseases (<xref ref-type="bibr" rid="B5">5</xref>). In addition, it is known that there is mitochondrial dysfunction in Parkinson&#x02019;s disease that can be treated by AMPK, which is identified as a mitochondrial biogenesis (<xref ref-type="bibr" rid="B6">6</xref>&#x02013;<xref ref-type="bibr" rid="B8">8</xref>). Recently, some findings show that AMPK plays an important role in bone metabolism. Besides, some <italic>in vitro</italic> studies revealing that AMPK modulators regulate bone cell function (<xref ref-type="bibr" rid="B9">9</xref>&#x02013;<xref ref-type="bibr" rid="B13">13</xref>). Also, some studies show that deficiency of AMPK &#x003B1; and &#x003B2; subunits in mice causes bone loss <italic>in vivo</italic> (<xref ref-type="bibr" rid="B14">14</xref>).</p>
<p>Based on the above mentioned points, it can be referred that AMPK deficiency in Parkinson&#x02019;s disease and schizophrenia may lead to osteoporosis. This can be used as a goal in treatment of osteoporosis in those disorders. In another word, nowadays there are some drugs available for both diseases but they have some side effect, which may lead to osteoporosis; by considering the fact that AMPK deficiency may cause osteoporosis, new drugs can be provided with AMPK supplement to reduce the osteoporosis symptoms. Surely, experimental trials are needed to validate our hypothesis.</p>
<sec id="S1">
<title>Conflict of Interest Statement</title>
<p>The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
</body>
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