<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE article  PUBLIC "-//NLM//DTD Journal Publishing DTD v3.0 20080202//EN" "http://dtd.nlm.nih.gov/publishing/3.0/journalpublishing3.dtd"><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" dtd-version="3.0" xml:lang="en" article-type="research article"><front><journal-meta><journal-id journal-id-type="publisher-id">JBM</journal-id><journal-title-group><journal-title>Journal of Biosciences and Medicines</journal-title></journal-title-group><issn pub-type="epub">2327-5081</issn><publisher><publisher-name>Scientific Research Publishing</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.4236/jbm.2022.105011</article-id><article-id pub-id-type="publisher-id">JBM-117316</article-id><article-categories><subj-group subj-group-type="heading"><subject>Articles</subject></subj-group><subj-group subj-group-type="Discipline-v2"><subject>Biomedical&amp;Life Sciences</subject></subj-group></article-categories><title-group><article-title>
 
 
  Can &lt;I&gt;Plasmodium falciparum&lt;/I&gt; Induce Homocysteinemia in Malaria Patients?
 
</article-title></title-group><contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Noé</surname><given-names>Yaméogo</given-names></name><xref ref-type="aff" rid="aff1"><sup>1</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Abdoul</surname><given-names>Karim Ouattara</given-names></name><xref ref-type="aff" rid="aff2"><sup>2</sup></xref><xref ref-type="corresp" rid="cor1"><sup>*</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Bapio</surname><given-names>Valérie Bazié</given-names></name><xref ref-type="aff" rid="aff3"><sup>3</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Alfred</surname><given-names>Rakissida Ouédraogo</given-names></name><xref ref-type="aff" rid="aff4"><sup>4</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Florencia</surname><given-names>Wendkuuni Djigma</given-names></name><xref ref-type="aff" rid="aff5"><sup>5</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Jacques</surname><given-names>Simporé</given-names></name><xref ref-type="aff" rid="aff5"><sup>5</sup></xref></contrib></contrib-group><aff id="aff1"><addr-line>Laboratoire de Biologie Moléculaires et de Génétique (LABIOGENE), UFR-SVT, Université Joseph KI-ZERBO, Ouagadougou, Burkina Faso</addr-line></aff><aff id="aff4"><addr-line>Centre Hospitalier Universitaire de Bogodogo, Ouagadougou, Burkina Faso</addr-line></aff><aff id="aff5"><addr-line>Centre de Recherche Biomoléculaire Pietro Annigoni (CERBA), Ouagadougou, Burkina Faso</addr-line></aff><aff id="aff3"><addr-line>Centre National de Recherche Scientifique et Technologique, Ouagadougou, Burkina Faso</addr-line></aff><aff id="aff2"><addr-line>Université Norbert Zongo (UNZ), Centre Universitaire de Manga, Koudougou, Burkina Faso</addr-line></aff><pub-date pub-type="epub"><day>09</day><month>05</month><year>2022</year></pub-date><volume>10</volume><issue>05</issue><fpage>117</fpage><lpage>128</lpage><history><date date-type="received"><day>16,</day>	<month>March</month>	<year>2022</year></date><date date-type="rev-recd"><day>22,</day>	<month>May</month>	<year>2022</year>	</date><date date-type="accepted"><day>25,</day>	<month>May</month>	<year>2022</year></date></history><permissions><copyright-statement>&#169; Copyright  2014 by authors and Scientific Research Publishing Inc. </copyright-statement><copyright-year>2014</copyright-year><license><license-p>This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/</license-p></license></permissions><abstract><p>
 
 
  Background: Plasmodium falciparum has developed elaborate strategies to survive in the hostile intracellular environment of the infected host cell, including resistance to oxidative stress. Cysteine is a metabolic product of homocysteine and a precursor of the antioxidant glutathione used by Plasmodium falciparum to escape harmful oxidation. 
  Objectives: In the present study we aimed to assess whether Plasmodium falciparum can induce homocysteinemia in malaria patients of Burkina Faso. 
  Methods: Eighty-five (85) individuals including 25 affected by severe malaria, 44 by simple malaria, and 12 negative controls for P. falciparum infection were included in the present study. An enzymatic assay of plasma homocysteinemia was performed using the Homocysteine Enzymatic Assay reagent (ref 05385415 190) on the Roche/ Hitachi Cobas c. 
  Results: The results of the present study show that the mean plasma homocysteine concentrations were 15.1 &#177; 8.4 μmol/L among patients with severe malaria, 14.0 &#177; 6.0 μmol/L in patients with uncomplicated malaria, and 12.6 &#177; 4.1 μmol/L in negative controls for malaria parasite. 
  Conclusions: Our findings suggest high homocysteinemia in malaria patients, especially in those with severe malaria. Monitoring homocysteinemia in the latter group will be useful to avoid complications when an elevated plasma level of homocysteine is a known risk factor for cardiovascular diseases.
 
</p></abstract><kwd-group><kwd>Homocysteine</kwd><kwd> Malaria</kwd><kwd> Burkina Faso</kwd></kwd-group></article-meta></front><body><sec id="s1"><title>1. Introduction</title><p>The essential amino acid, methionine, is the only source of homocysteine (Hcy) in humans and is found in dietary protein [<xref ref-type="bibr" rid="scirp.117316-ref1">1</xref>]. Hcy, a sulfur-containing non-protein amino acid is an essential intermediate in the normal mammalian metabolism of methionine. Hcy levels are maintained dynamically by either a remethylation into methionine or transsulfuration into cysteine (<xref ref-type="fig" rid="fig1">Figure 1</xref>). Part of homocysteine is remethylated in the liver by the action of betaine-Hcy methyltransferase using methyltetrahydrofolate and betaine as methyl donors, respectively. Thus, both CBS, MS and MTHFR enzyme activity as well as the availability of THF (tetrahydrofolates) from folic acid metabolism play an important role in cell Hcy balance</p><p>[<xref ref-type="bibr" rid="scirp.117316-ref2">2</xref>]. Normal values of plasmatic levels of Hcy have been described as around 5 - 15 μmol/L when higher levels of Hcy are put into three main categories: mild (15 to 30 μmol/L), moderate (30 to 100 μmol/L), and severe, greater than 100 μmol/L [<xref ref-type="bibr" rid="scirp.117316-ref3">3</xref>]. An elevated blood level of homocysteine is an independent risk factor for cardiovascular disease [<xref ref-type="bibr" rid="scirp.117316-ref4">4</xref>], neuropsychiatric pathologies such as Alzheimer’s disease [<xref ref-type="bibr" rid="scirp.117316-ref5">5</xref>], neural tube closure defect [<xref ref-type="bibr" rid="scirp.117316-ref6">6</xref>] [<xref ref-type="bibr" rid="scirp.117316-ref7">7</xref>], depressive disorders [<xref ref-type="bibr" rid="scirp.117316-ref8">8</xref>] and schizophrenia [<xref ref-type="bibr" rid="scirp.117316-ref9">9</xref>] [<xref ref-type="bibr" rid="scirp.117316-ref10">10</xref>] [<xref ref-type="bibr" rid="scirp.117316-ref11">11</xref>]. Hyper-homocysteinemia could be due to the inhibition of the remethylation pathway or saturation of the transsulfuration pathway with alteration of coordinate regulation of homocysteine metabolism by S-adenosylme-thionine. Moderate hyperhomocysteinemia is prevalent in developed countries due to increasing food intake of animal proteins, a source of methionine and homocysteine and also the processing and preservation of foodstuffs, susceptible to induce a lack of folic acid, vitamins B6 and B12, required for homocysteine metabolism [<xref ref-type="bibr" rid="scirp.117316-ref12">12</xref>].</p><p>Studies reported that hyperhomocysteinemia is more common in the Caucasian population with more than 15% of people affected by an elevated blood homocysteinemia [<xref ref-type="bibr" rid="scirp.117316-ref13">13</xref>] while the plasma concentration of Hcy is lower in the sub-Saharan African populations than in the Mediterranean populations [<xref ref-type="bibr" rid="scirp.117316-ref13">13</xref>] [<xref ref-type="bibr" rid="scirp.117316-ref14">14</xref>].</p><p>Such a difference is thought to be due to the variable frequency of MTHFR polymorphism in these populations [<xref ref-type="bibr" rid="scirp.117316-ref15">15</xref>]. In Burkina Faso, a study reported a low blood level of homocysteinemia in the general population [<xref ref-type="bibr" rid="scirp.117316-ref13">13</xref>]. The transsulfuration pathway is a metabolic pathway where the transfer of sulfur from homocysteine to cysteine occurs and promotes the generation of glutathione (GSH) (<xref ref-type="fig" rid="fig1">Figure 1</xref>). The complexity of the Hcy and methionine metabolic pathways and the balance required for hemostasis is strongly influenced by the presence of Plasmodium falciparum [<xref ref-type="bibr" rid="scirp.117316-ref16">16</xref>]. Due to the drastic changes observed in the metabolism of GSH in red blood cells infected with P. falciparum, de novo synthesis of the tripeptide was found to be required for the parasite survival [<xref ref-type="bibr" rid="scirp.117316-ref17">17</xref>]. P. falciparum employs a complex thioredoxin and glutathione system to maintain the intracellular redox balance [<xref ref-type="bibr" rid="scirp.117316-ref18">18</xref>]. The redox system plays an important role in the survival of P. falciparum and the progression of the associated disease [<xref ref-type="bibr" rid="scirp.117316-ref19">19</xref>]. Red blood cells can further expel homocysteine accumulated in plasma where it is known to concentrate during malaria infection. These observations are in line with the fact that malaria patients have elevated levels of plasma homocysteine [<xref ref-type="bibr" rid="scirp.117316-ref20">20</xref>]. Plasmodium falciparum uses the polyamine pathway (<xref ref-type="fig" rid="fig1">Figure 1</xref>), which is essential for its proliferation and differentiation, imposing oxidative stress on the host cell [<xref ref-type="bibr" rid="scirp.117316-ref21">21</xref>], following the use of glutathione [<xref ref-type="bibr" rid="scirp.117316-ref22">22</xref>]. This reduces the remethylation of homocysteine to methionine and increases the pathway of transsulfuration.</p><p>The folate pathway is an important carbon source for P. falciparum in the nucleic acid synthesis. One of the most important carbon transfer reactions in malaria parasites is the methylation of the nucleotide deoxyuridine 5'-monophos-phate to deoxythymidine 5'-monophosphate, a precursor to deoxythymidine 5'-triphosphate required for the synthesis of DNA, in the thymidylate cycle [<xref ref-type="bibr" rid="scirp.117316-ref23">23</xref>]. The parasite is also able to oxidize vitamin B12 and thus inhibit the activation of methionine synthase required for remethylation of homocysteine into methionine, leading to increase plasma level of homocysteine in infected patients [<xref ref-type="bibr" rid="scirp.117316-ref16">16</xref>].</p><p>Mobilization of glutathione by the malaria parasite to resist oxidative stress promotes the accumulation of homocysteine in the host cell. Previous studies reported an association between human genetic factors and the progression to severe malaria with an increasing level of plasma Hcy [<xref ref-type="bibr" rid="scirp.117316-ref24">24</xref>] [<xref ref-type="bibr" rid="scirp.117316-ref25">25</xref>].</p><p>A methionine-rich diet could influence plasma levels of Hcy in the general population. Deep knowledge of homocysteinemia in the Burkinabe population is important to reduce morbidity and mortality due to malaria. Homocysteinemia is generally increased in renal pathology and some authors recommend that research on total homocysteinemia in the general population should include markers of renal function [<xref ref-type="bibr" rid="scirp.117316-ref26">26</xref>]. According to WHO criteria, malaria is considered severe when one or more vital functions of the body (kidneys, liver, etc.) are affected by the disease. In line with such recommendation, we perform some biochemical parameters along with the measurement of homocysteinemia in the present study which aimed to assess whether Plasmodium falciparum can induce homocysteinemia in malaria patients of Burkina Faso.</p></sec><sec id="s2"><title>2. Materials and Methods</title><sec id="s2_1"><title>2.1. Setting and Type of Study</title><p>This cross-sectional study was carried out from September to December 2020 in Ouagadougou, the capital of Burkina Faso, with approximately 2,966,307 inhabitants [<xref ref-type="bibr" rid="scirp.117316-ref27">27</xref>]. Ouagadougou is located in the plateau central region with a Sudano-Sahelian climate and two seasons. The dry season is from October to May and the wet season is from June to September. This climate is characterized by the seasonal transmission of malaria mainly during the wet season. However, the presence of peripheral artificial water reservoirs (dam) and residual (open gutters) through the city and the galloping urbanization, leads to a permanent transmission of malaria throughout the year.</p></sec><sec id="s2_2"><title>2.2. Study Population</title><p>The study population consisted of eighty-five (85) patients seen in general medicine at three health facilities in Ouagadougou, CHU de Bogodogo, CMA de Kossodo and Clinique ILBOUDO Bruno. Patients with suspected malaria and referred to the laboratory for a thick smear for malaria diagnosis were included in the study.</p></sec><sec id="s2_3"><title>2.3. Sampling</title><p>A sample of 8 mL of venous blood was collected in three different tubes (EDTA, Sec and/or heparinized) and used for Blood Formula Count (CBC) and thick drop. EDTA tubes were centrifuged at 3000 rpm for 5 mins and aliquots of pellet and plasma were carried out in cryotubes and stored at −80˚C for the homocysteine assay. The blood in the dry or heparinized tubes was separated into pellet and plasma or serum for further biochemical testing.</p></sec><sec id="s2_4"><title>2.4. Biological Analysis</title><p>The thick drop was performed according to the standard method and stained with Giemsa diluted 1/10 [<xref ref-type="bibr" rid="scirp.117316-ref27">27</xref>].</p><p>The various hematological parameters were analyzed using the SYSMEX XN-350 device. The enzymatic assay of plasma homocysteine was carried out with the Homocysteine Enzymatic Assay reagent (ref 05385415 190) on the Cobas 6000 C501, E601 device. The assay of transaminases (ASAT: aspartate aminotransferases and ALAT: alanine aminotransferases), serum creatinine and C-reactive protein (CRP) was carried out using the same Cobas device.</p></sec><sec id="s2_5"><title>2.5. Statistical Analysis</title><p>Data were processed using Excel 2019 software (Microsoft) and SPSS&#174; software version 20 (SPSS Inc., Chicago, USA). Pearson’s Chi-square test was used for the comparisons and any P value &lt; 0.05 was considered statistically significant.</p></sec><sec id="s2_6"><title>2.6. Ethical Consideration</title><p>The study received the approval of the Burkina Faso health research ethics committee (deliberation N˚ 2020-10-232) as well as that of the internal ethics committee of CHU-B. All participants or legal guardians of those under the age of 18 gave their free and informed consent to participate in the present study.</p></sec></sec><sec id="s3"><title>3. Results</title><sec id="s3_1"><title>3.1. Sociodemographic Data</title><p>The present study population consisted of 40% (34/85) of men (<xref ref-type="fig" rid="fig2">Figure 2</xref>). The mean age was 20.7 &#177; 22.2 years. The most represented age group (34.13%) was children (29/85) under 5 years old (<xref ref-type="fig" rid="fig2">Figure 2</xref>).</p></sec><sec id="s3_2"><title>3.2. Thick Smear Assay and Hematological Parameters</title><p>The thick smear assay revealed 73 cases of malaria including 25 severe malaria and 48 uncomplicate malaria against 12 malaria negative individuals (<xref ref-type="table" rid="table1">Table 1</xref>). The mean age of women was 23.9 &#177; 22.7 years compared to 15.9 &#177; 20.8 years for men in the study population. The mean age was 13.1 &#177; 12.2 years for patients with severe malaria versus 44.5 &#177; 29.6 years for malaria negative subjects. An average parasite density of 120827.6 &#177; 244,587 trophozoites/&#181;l was observed in patients with severe malaria compared to 2393.8 &#177; 2748.4 trophozoites/&#181;l in patients with uncomplicated malaria. A mean hemoglobin level of 6.7 &#177; 4.0 g/dl was found in patients with severe malaria versus 9.8 &#177; 3.3 g/dl in malaria negative controls. The mean platelet count in the study population was greater than 150,000 platelets/&#181;l of blood (<xref ref-type="table" rid="table1">Table 1</xref>).</p></sec><sec id="s3_3"><title>3.3. Biochemical Parameters</title><p>The mean level of transaminases was less than 35 IU/&#181;l (<xref ref-type="table" rid="table2">Table 2</xref>) while that of CRP was above the reference value (&lt;6 mg/L) (<xref ref-type="table" rid="table2">Table 2</xref>). Elevated mean serum creatinine was observed in females (192.7 &#181;mol/L) as well as in malaria negative controls (218.9 &#181;mol/L). The mean plasma homocysteinemia level was 14.1 &#177; 5.4 &#181;mol/L in men and 14.2 &#177; 7.3 &#181;mol/L in women. In patients with severe malaria the mean plasma homocysteinemia was 15.1 &#177; 8.4 &#181;mol/L versus 14.0 &#177; 6.0 &#181;mol/L in individuals with moderate malaria and 12.6 &#177; 4.1 &#181;mol/L in individuals not infected with Plasmodium falciparum (<xref ref-type="table" rid="table2">Table 2</xref>).</p><table-wrap id="table1" ><label><xref ref-type="table" rid="table1">Table 1</xref></label><caption><title> Thick smear results, gender, malaria classification and hematological parameters</title></caption><table><tbody><thead><tr><th align="center" valign="middle" ></th><th align="center" valign="middle" ></th><th align="center" valign="middle" >Age</th><th align="center" valign="middle" >Parasite density (trophozo&#239;tes/&#181;L)<sup>α</sup></th><th align="center" valign="middle" >Hb Level (g/dl)<sup>β</sup></th><th align="center" valign="middle" >Leukocytes (Number/&#181;l)<sup>&#162;</sup></th><th align="center" valign="middle" >Rate of platelets (Number/&#181;l)<sup>&#167;</sup></th><th align="center" valign="middle" >Hcy (&#181;mol/L)<sup>αβ&#162;&#167;</sup></th></tr></thead><tr><td align="center" valign="middle"  rowspan="2"  >Sex</td><td align="center" valign="middle" >Male</td><td align="center" valign="middle" >15.9 (&#177;20.8)</td><td align="center" valign="middle" >13622.9 (&#177;32606.4)</td><td align="center" valign="middle" >9.3 (&#177;2.3)</td><td align="center" valign="middle" >11097.6 (&#177;8658.2)</td><td align="center" valign="middle" >151500.0 (&#177;813.8%)</td><td align="center" valign="middle" >14.1 (&#177;5.4)</td></tr><tr><td align="center" valign="middle" >Female</td><td align="center" valign="middle" >23.9 (&#177;22.7)</td><td align="center" valign="middle" >52400.2 (&#177;179996.5)</td><td align="center" valign="middle" >9.3 (&#177;2.9229)</td><td align="center" valign="middle" >8762.3 (&#177;4139.4)</td><td align="center" valign="middle" >195100.0 (&#177;113328.3)</td><td align="center" valign="middle" >14.2 (&#177;7.3)</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Thick smear results</td><td align="center" valign="middle" >Positive</td><td align="center" valign="middle" >16.7 (&#177;18.2)</td><td align="center" valign="middle" >42953.3 (&#177;152145.9)</td><td align="center" valign="middle" >9.3 (&#177;3.5)</td><td align="center" valign="middle" >9597.7 (&#177;5934.5)</td><td align="center" valign="middle" >174415.1 (&#177;104592.7)</td><td align="center" valign="middle" >14.4 (&#177;6.9)</td></tr><tr><td align="center" valign="middle" >Negative</td><td align="center" valign="middle" >44.5 (&#177;29.6)</td><td align="center" valign="middle" >0.00</td><td align="center" valign="middle" >9.8 (&#177;3.3)</td><td align="center" valign="middle" >10297.50 (&#177;9050.8)</td><td align="center" valign="middle" >197400.0 (&#177;98357.0)</td><td align="center" valign="middle" >12.6 (&#177;4.1)</td></tr><tr><td align="center" valign="middle"  rowspan="3"  >Malaria</td><td align="center" valign="middle" >Severe</td><td align="center" valign="middle" >13.1 (&#177;12.2)</td><td align="center" valign="middle" >120827.6 (&#177;244587.6)</td><td align="center" valign="middle" >6.7 (&#177;4.0)</td><td align="center" valign="middle" >8649.6 (&#177;6334.4)</td><td align="center" valign="middle" >155240.0 (&#177;93505.0)</td><td align="center" valign="middle" >15.1 (&#177;8.4)</td></tr><tr><td align="center" valign="middle" >Simple</td><td align="center" valign="middle" >18.7 (&#177;20.5)</td><td align="center" valign="middle" >2393.8 (&#177;2748.4)</td><td align="center" valign="middle" >8.3 (&#177;3.6)</td><td align="center" valign="middle" >10091.5 (&#177;5721.4)</td><td align="center" valign="middle" >184402.1 (&#177;109528.7)</td><td align="center" valign="middle" >14.0 (&#177;6.0)</td></tr><tr><td align="center" valign="middle" >Negative</td><td align="center" valign="middle" >44.5 (&#177;29.6)</td><td align="center" valign="middle" >0.00</td><td align="center" valign="middle" >9.8 (&#177;3.3)</td><td align="center" valign="middle" >10297.5 (&#177;9050.8)</td><td align="center" valign="middle" >197400.0 (&#177;98357.0)</td><td align="center" valign="middle" >12.6 (&#177;4.1)</td></tr><tr><td align="center" valign="middle" >Total</td><td align="center" valign="middle" ></td><td align="center" valign="middle" >20.7 (&#177;22.2)</td><td align="center" valign="middle" >36889.3 (&#177;141660.9)</td><td align="center" valign="middle" >9.4 (&#177;3.5)</td><td align="center" valign="middle" >9696.5 (&#177;6401.1)</td><td align="center" valign="middle" >177660.0 (&#177;103481.8)</td><td align="center" valign="middle" >14.1 (&#177;6.6)</td></tr></tbody></table></table-wrap><p>α: p = 0.419; β: p = 0.404; &#162;: p = 0.366; &#167;: p = 0.575.</p><table-wrap id="table2" ><label><xref ref-type="table" rid="table2">Table 2</xref></label><caption><title> GE results, Gender, malaria classification and biochemical parameters</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Parameters</th><th align="center" valign="middle" ></th><th align="center" valign="middle" >ASAT (UI/L)</th><th align="center" valign="middle" >ALAT (UI/L)</th><th align="center" valign="middle" >CRP (mg/L)</th><th align="center" valign="middle" >Cr&#233;atinine (&#181;mol/L)</th><th align="center" valign="middle" >Hcy (&#181;mol/L)<sup>?pound;</sup></th></tr></thead><tr><td align="center" valign="middle"  rowspan="2"  >Sex</td><td align="center" valign="middle" >Male</td><td align="center" valign="middle" >24.4 (&#177;3.6)</td><td align="center" valign="middle" >22.4 (&#177;4.9)</td><td align="center" valign="middle" >53.6 (&#177;54.8)</td><td align="center" valign="middle" >75.9 (&#177;77.8)</td><td align="center" valign="middle" >14.1 (&#177;5.4)</td></tr><tr><td align="center" valign="middle" >Female</td><td align="center" valign="middle" >29.6 (&#177;28.9)</td><td align="center" valign="middle" >26.4 (&#177;32.1)</td><td align="center" valign="middle" >102.4 (&#177;146.1)</td><td align="center" valign="middle" >192.7 (&#177;491.8)</td><td align="center" valign="middle" >14.2 (&#177;7.3)</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Thick smear results<sup>?/span&gt;</sup></td><td align="center" valign="middle" >Positive</td><td align="center" valign="middle" >36.0 (&#177;25.4)</td><td align="center" valign="middle" >16.6 (&#177;7.1)</td><td align="center" valign="middle" >119.5 (&#177;145.6)</td><td align="center" valign="middle" >51.1 (&#177;12.2)</td><td align="center" valign="middle" >14.4 (&#177;6.9)</td></tr><tr><td align="center" valign="middle" >Negative</td><td align="center" valign="middle" >34.1 (&#177;25.9)</td><td align="center" valign="middle" >27.4 (&#177;28.9)</td><td align="center" valign="middle" >36.2 (&#177;50.3)</td><td align="center" valign="middle" >218.9 (&#177;510.3)</td><td align="center" valign="middle" >12.6 (&#177;4.1)</td></tr><tr><td align="center" valign="middle"  rowspan="3"  >Malaria<sup>&#163;</sup></td><td align="center" valign="middle" >Serious</td><td align="center" valign="middle" >18.0 (&#177;3.2)</td><td align="center" valign="middle" >21.7 (&#177;5.6)</td><td align="center" valign="middle" >140.9 (&#177;135.3)</td><td align="center" valign="middle" >44.3 (&#177;6.1)</td><td align="center" valign="middle" >15.1 (&#177;8.4)</td></tr><tr><td align="center" valign="middle" >Simple</td><td align="center" valign="middle" >24.0 (&#177;4.3)</td><td align="center" valign="middle" >11.6 (&#177;6.1)</td><td align="center" valign="middle" >112.3 (&#177;156.0)</td><td align="center" valign="middle" >55.2 (&#177;13.6)</td><td align="center" valign="middle" >14.0 (&#177;6.0)</td></tr><tr><td align="center" valign="middle" >Negative</td><td align="center" valign="middle" >34.1 (&#177;25.9)</td><td align="center" valign="middle" >27.4 (&#177;28.9)</td><td align="center" valign="middle" >36.2 (&#177;50.3)</td><td align="center" valign="middle" >218.9 (&#177;510.3)</td><td align="center" valign="middle" >12.6 (&#177;4.1)</td></tr><tr><td align="center" valign="middle" >Total</td><td align="center" valign="middle" ></td><td align="center" valign="middle" >34.5 (&#177;24.2)</td><td align="center" valign="middle" >25.0 (&#177;25.6)</td><td align="center" valign="middle" >83.8 (&#177;120.2)</td><td align="center" valign="middle" >151.8 (&#177;397.4)</td><td align="center" valign="middle" >14.1 (&#177;6.6)</td></tr></tbody></table></table-wrap><p>? p = 0.452; &#163;: p = 0.419.</p></sec></sec><sec id="s4"><title>4. Discussion</title><p>The present study assessed the influence of Plasmodium falciparum infection on plasma level of homocysteine in people from Burkina Faso. An elevated plasma levels of Hcy was found in patients with severe malaria (15.1 &#177; 8.4 &#181;mol/L) compared to those with uncomplicated malaria (14.0 &#177; 6.0 &#181;mol/L) or negative controls for malaria (12.6 &#177; 4.1 &#181;mol/L).</p><p>Our findings are in line with those of Chiellemi et al. [<xref ref-type="bibr" rid="scirp.117316-ref16">16</xref>] who reported a high level of plasma homocysteine in all subjects with P. falciparum malaria and correlated positively with the disease severity and the number of parasites. This increase could be due to the oxidative stress exerted by the P. falciparum infection and requires higher consumption of glutathione [<xref ref-type="bibr" rid="scirp.117316-ref16">16</xref>] [<xref ref-type="bibr" rid="scirp.117316-ref28">28</xref>] [<xref ref-type="bibr" rid="scirp.117316-ref29">29</xref>]. Altogether the hyperhomocysteinemia in patients with severe malaria in the present study suggests routine dosing for plasma Hcy as a marker of malaria severity in symptomatic individuals.</p><p>Plasma levels of homocysteine in the present study were similar in both men (14.1 &#177; 5.4 &#181;mol/L) and women (14.2 &#177; 7.3 &#181;mol/L) although Simpore et al. [<xref ref-type="bibr" rid="scirp.117316-ref14">14</xref>] reported that plasma levels of total Hcy are particularly low in black females. Low homocysteinemia has been reported infertile women (6.8 &#177; 1.2 &#181;mol/L) against high homocysteinemia in postmenopausal women (16.4 &#177; 6.6 &#181;mol/L) in Burkina [<xref ref-type="bibr" rid="scirp.117316-ref15">15</xref>]. Women were predominant in our study population due to their proportion in the population of Burkina Faso [<xref ref-type="bibr" rid="scirp.117316-ref27">27</xref>], and their high attendance at health centers as well as their ease adhesion to research studies compared to men.</p><p>The homocysteinemia (12.6 &#181;mol/L) found in the malaria negative controls of the present study is higher than the plasma concentration of homocysteine reported in Burkina (6.9 &#177; 1.3 &#181;mol/L for men and 5.9 &#177; 1.9 &#181;mol/L for women) [<xref ref-type="bibr" rid="scirp.117316-ref13">13</xref>] [<xref ref-type="bibr" rid="scirp.117316-ref14">14</xref>], and similar to the levels of 13.5 &#181;mol/L found in Togo and 14.1 &#181;mol/L in Benin [<xref ref-type="bibr" rid="scirp.117316-ref30">30</xref>]. In fact, it is well known that homocysteinemia varies according to methionine-rich diet or genetic polymorphisms of the enzymes involved in the homocysteine metabolism [<xref ref-type="bibr" rid="scirp.117316-ref14">14</xref>] [<xref ref-type="bibr" rid="scirp.117316-ref25">25</xref>]. A multidisciplinary approach thus fixing the food factor could better help to understand the influence of the infection with Plasmodium falciparum on the plasma concentration of homocysteine in Burkina Faso.</p><p>Chillemi et al. [<xref ref-type="bibr" rid="scirp.117316-ref16">16</xref>] reported that elevated level of plasma homocysteine was negatively correlated with hemoglobin levels and patient ages. However, no correlation was found between plasma homocysteinemia and hematological, biochemical, or socio-demographic parameters in the present study. The relatively low mean age (20.7 years, <xref ref-type="table" rid="table1">Table 1</xref>) of our study population is a factor to consider since homocysteinemia increases with age.</p><p>The serum levels of L-alanine aminotransferase (ALAT) and L-aspartate aminotransferase (ASAT) is a primary screening tool for detecting acute liver injury [<xref ref-type="bibr" rid="scirp.117316-ref31">31</xref>]. The mean values of transaminases in the present study suggest poor effect of homocysteinemia on liver function. CRP with an average of 83.8 g/L was overall elevated in our study population and suggests inflammation in most study participants. Elevated serum creatinine due to renal failure was also found in women (192.7 &#181;mol/L mean). It is well known that infection with Plasmodium falciparum leads to a decrease in the hemoglobin level through the destruction of infected red blood cells [<xref ref-type="bibr" rid="scirp.117316-ref32">32</xref>]. A low hemoglobin level (6.7 &#177; 4 g/dl) was observed in patients with severe malaria in our study population.</p><p>Hyperhomocysteinemia is known to be a risk factor in the occurrence of cardiovascular disease, renal failure, and diabetes [<xref ref-type="bibr" rid="scirp.117316-ref33">33</xref>] [<xref ref-type="bibr" rid="scirp.117316-ref34">34</xref>] [<xref ref-type="bibr" rid="scirp.117316-ref35">35</xref>]. We report for the first time in Burkina Faso enzymatic assay of plasma homocysteine using routine biochemistry platform with the perspective of routine dosage of homocysteine in association with various pathologies. This will make it possible to investigate the divergences in the literature in the specific context of Burkina Faso. Indeed, it has been reported that the administration of products derived from folate as well as vitamins B6 and B12 leading to a drop in homocysteinemia has not proved their effectiveness in the occurrence of various pathologies [<xref ref-type="bibr" rid="scirp.117316-ref36">36</xref>] [<xref ref-type="bibr" rid="scirp.117316-ref37">37</xref>] [<xref ref-type="bibr" rid="scirp.117316-ref38">38</xref>]. Drugs long used against malaria (pyrimethamine, sulfadoxine) exploit the oxidative power that prevents the parasite from avoiding oxidation in the red blood cells. These oxidizing drugs are therefore able to destroy the anti-oxidative system of plasmodium falciparum. Pyrimethamine and many other antifolates bind to the parasite tetrahydrofolate dehydrogenase more tightly than to the host enzyme [<xref ref-type="bibr" rid="scirp.117316-ref39">39</xref>]. Parasites such as Plasmodium falciparum do not have dihydro-neopterin aldolase but can circumvent this obstacle by using another enzyme such as pyruvoyltetrahydropterin synthase [<xref ref-type="bibr" rid="scirp.117316-ref40">40</xref>]. Plasmodium can also import folate cycle derivatives from the host for its own needs [<xref ref-type="bibr" rid="scirp.117316-ref41">41</xref>]. The antioxidant drugs used act to block certain enzymes that contribute to the formation of tetrahydrofolate. Blocking these enzymes prevents the development of plasmodium falciparum in the host cells. Molecules that can prevent the parasite from avoiding oxidation inside the red blood cell will therefore help to inhibit the parasite and limit its development in the host organism.</p></sec><sec id="s5"><title>5. Conclusion</title><p>The present study suggests a tendency for the increased plasma concentration of homocysteinemia induced by Plasmodium falciparum infection. It opens up prospects for multidisciplinary studies to better define the influence of Plasmodium falciparum on homocysteinemia and its association with various pathologies.</p></sec><sec id="s6"><title>Acknowledgments</title><p>We express our deep gratitude to all the staff of CERBA/LABIOGENE and to all those who helped to carry out this study.</p></sec><sec id="s7"><title>Author Contributions</title><p>Conceptualization: No&#233; Yam&#233;ogo, Florencia Wendkuuni Djigma and Jacques Simpor&#233;; Methodology: No&#233; Yam&#233;ogo, Alfred Rakissida Ou&#233;draogo; Bapio Val&#233;rie Bazi&#233;, Alfred Rakissida Ou&#233;draogo, and Jacques Simpor&#233;; Software, validation: No&#233; Yam&#233;ogo, Bapio Val&#233;rie Bazi&#233; and Jacques Simpor&#233;; Formal analysis: No&#233; Yam&#233;ogo, Alfred Rakissida Ou&#233;draogo, Bapio Val&#233;rie Bazi&#233;; Investigation: No&#233; Yam&#233;ogo, Alfred Rakissida Ou&#233;draogo, Bapio Val&#233;rie Bazi&#233; and Jacques Simpor&#233;; resources, Jacques Simpor&#233;; Data curation, writing-original draft preparation: No&#233; Yam&#233;ogo, Alfred Rakissida Ou&#233;draogo and Jacques Simpor&#233;; Writing review and editing: No&#233; Yam&#233;ogo, Alfred Rakissida Ou&#233;draogo, Bapio Val&#233;rie Bazi&#233;, Alfred Rakissida Ou&#233;draogo, Florencia Wendkuuni Djigma, Jacques Simpor&#233;; Visualization, supervision: Jacques Simpor&#233;; Project administration: Jacques Simpor&#233;, Florencia Wendkuuni Djigma; Funding acquisition: No&#233; Yam&#233;ogo and Jacques Simpor&#233;. All authors have read and agreed to the published version of the manuscript.</p></sec><sec id="s8"><title>Conflicts of Interest</title><p>The authors declare that they have no competing interests.</p></sec><sec id="s9"><title>Cite this paper</title><p>Yam&#233;ogo, N., Ouattara, A.K., Bazi&#233;, B.V., Ou&#233;draogo, A.R., Djigma, F.W. and Simpor&#233;, J. (2022) Can Plasmodium falciparum Induce Homocysteinemia in Malaria Patients? Journal of Biosciences and Medicines, 10, 117-128. https://doi.org/10.4236/jbm.2022.105011</p></sec></body><back><ref-list><title>References</title><ref id="scirp.117316-ref1"><label>1</label><mixed-citation publication-type="other" xlink:type="simple">Rasmussen, K. and Moller, J. (2000) Total Homocysteine Measurement in Clinical Practice. 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