research article circadian rhythms of oxidative stress

Research ArticleCircadian Rhythms of Oxidative Stress Markers and MelatoninMetabolite in Patients with Xeroderma Pigmentosum Group A

Rie Miyata12 Naoyuki Tanuma13 Hiroshi Sakuma1 and Masaharu Hayashi1

1Department of Brain Development and Neural Regeneration TokyoMetropolitan Institute of Medical Science Tokyo 156-8506 Japan2Department of Pediatrics Tokyo-Kita Medical Center Tokyo 171-0053 Japan3Department of Pediatrics Tokyo Metropolitan Fuchu Medical Center for the Disabled Tokyo 183-8553 Japan

Correspondence should be addressed to Rie Miyata rie88miyatayahoocojp

Received 17 February 2016 Accepted 10 April 2016

Academic Editor Gregory Durand

Copyright copy 2016 Rie Miyata et al This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Xeroderma pigmentosum group A (XPA) is a genetic disorder in DNA nucleotide excision repair (NER) with severe neurologicaldisorders in which oxidative stress and disturbed melatonin metabolism may be involved Herein we confirmed the diurnalvariation of melatonin metabolites oxidative stress markers and antioxidant power in urine of patients with XPA and age-matchedcontrols using enzyme-linked immunosorbent assay (ELISA) The peak of 6-sulfatoxymelatonin a metabolite of melatonin wasseen at 600 in both the XPA patients and controls though the peak value is lower specifically in the younger age group of XPApatients The older XPA patients demonstrated an increase in the urinary levels of 8-hydroxy-21015840-deoxyguanosine and hexanoyl-lysine a marker of oxidative DNA damage and lipid peroxidation having a robust peak at 600 and 1800 respectively In additionthe urinary level of total antioxidant power was decreased in the older XPA patients Recently it is speculated that oxidative stressand antioxidant properties may have a diurnal variation and the circadian rhythm is likely to influence the NER itself We believethat the administration of melatonin has the possibility of ameliorating the augmented oxidative stress in neurodegenerationespecially in the older XPA patients modulating the melatonin metabolism and the circadian rhythm

1 Introduction

Xeroderma pigmentosum (XP) a genetic disorder in DNAnucleotide excision repair (NER) is characterized by skinhypersensitivity to sunlight and progressive neurologicalimpairment [1] There are eight complementation subgroupsof XP and group A (XPA) is common in Japan showingsevere neurological disorders such as mental deteriorationcerebellar ataxia extrapyramidal abnormalities and neu-ronal deafness but no effective treatment has been developedfor neurological disorders [2] Oxidative stress originatesfrom an imbalance between the production of reactive oxy-gen species and reactive nitrogen species and the antioxidantcapacities of cells and organs [3] Oxidative stress has beenconfirmed to play a role in adult-onset neurodegenerativediseases such as Alzheimerrsquos disease [4] and we confirmedthe involvement of oxidative neuronal damage in child-onsetand adult neurodegenerative diseases such as dentatorubral-pallidoluysian atrophy and superficial siderosis [5 6] We

clarified the accumulation of oxidative stress markers inthe basal ganglia in autopsy rains in XPA and Cockaynesyndrome (CS) having a genetic defect in transcription-coupled repair which results in multiple organ impairmentand various neurological disorders [7] In addition wereported an increase in the urinary levels of oxidative stressmarkers in both XPA and CS in the preliminary analysis [8]

Melatonin is a functionally pleiotropic and neuroen-docrine molecule and is produced mainly by the pinealgland under the control of the suprachiasmatic nucleus [9]Melatonin regulates circadian rhythm and plays a role inthe transduction of the chronobiological actions of multiplehormones In addition it also has antioxidant propertiesand anti-inflammatory abilities and is likely to be one oftherapeutic tools for neurological disorders such as multiplesclerosis and Huntingtonrsquos disease [10] Melatonin secretionhas a 24-hour rhythm in which the peak is during themidnight [11] We preliminarily examined the urinary levelof melatonin metabolite in XPA and CS which was reduced

Hindawi Publishing CorporationOxidative Medicine and Cellular LongevityVolume 2016 Article ID 5741517 5 pageshttpdxdoiorg10115520165741517

2 Oxidative Medicine and Cellular Longevity

predominantly in CS patients suffering from the disturbedcircadian rhythms of sleep-wakefulness and body tempera-ture regulation [12]

Recently redox regulation andor oxidative stress hasbeen reported to have diurnal variation and the circadianrhythms of oxidative stress markers and antioxidant enzymeshave been examined in healthy subjects and patients withneurological disorders [13] Nevertheless the relationshipsin diurnal variation between melatonin and oxidative stressmarkers still remain to be investigated Herein we analyzedthe circadian rhythms of oxidative stress markers and mela-tonin metabolites in urine of patients with XPA

2 Materials and Methods

We analyzed the urine from 8 patients with geneticallyconfirmed XPA and 8 normal controls aged from 6 to 37years It is well known that melatonin secretion varies by ageThe levels of plasma melatonin and its urinary metabolitesare high in infancy and early children decline dramaticallyaround adolescence and keep reducing gradually in adultsand aged people [14]

Accordingly we divided both XPA patients and controlsinto younger and older age groups consisting of threesubjects each less than 15 years and five ones each equalto and more than 15 years respectively Urine sampleswere collected four times a day (at 000 0600 1200 and1800) All specimens were stored at minus80∘C in a deep freezeravoiding lights Consents were granted from all parentsof patients and child controls and adult controls Thisanalysis was approved by the Ethical Committee of TokyoMetropolitan Institute of Medical Science We measured theurinary concentrations of 6-sulfatoxymelatonin (6-SM) amain metabolite of melatonin a marker of oxidative DNAdamage 8-hydroxy-21015840-deoxyguanosine (8-OHdG) an earlystage marker of lipid peroxidation hexanoyl-lysine adduct(HEL) and total antioxidant power (TAO) respectively aspreviously reported [8 12] We used commercially availableenzyme-linked immunosorbent assay (ELISA) kits for 6-SM (GenWay Biotech CA USA) 8-OHdG and HEL (JapanInstitute for the Aging Shizuoka Japan) and TAO (OxfordBiomedical Research MI USA) respectively

The results were normalized to urine concentration ofcreatinine (Cre) except TAO Correlations among 6-SM 8-OHdG HEL and TAO at each time point were confirmed bySpearmanrsquos rank correlation coefficient

3 Results

The peak of urinary 6-SM was identified at 600 in theyounger and older age group of both controls and all XPApatients and the peak value was reduced by age (Figure 1)The XPA patients demonstrated a lower peak value whichwas approximately one-third and half of each of those incontrols The urinary levels of 8-OHdG were low and lackedthe diurnal variation in the younger age group in bothcontrols and XPA patients (Figure 2(a)) In the older agegroup the urinary levels of 8-OHdG were increased in

600 1200 18000000102030405060708090100

(ngmgC

re)

XPAControl

(a)

000 600 1200 1800

XPAControl

0102030405060708090100

(ngmgC

re)

(b)

Figure 1 Circadian rhythm of urinary levels of 6-sulfatoxymela-tonin (6-SM) (ngmgCre) in younger age group (a) and older agegroup (b) Solid and dotted lines denote values of patients withxeroderma pigmentosum group A (XPA) and controls respectively

the XPA patients but not in controls in which the robust peakwas identified at 600 (Figure 2(b))The urinary levels of HELwere low and lacked the diurnal variation in the younger agegroup in both controls and XPA patients (Figure 3(a)) In theolder age group the urinary levels of 8-OHdG and HEL wereincreased in the XPA patients but not in controls in whichthe robust peak was identified at 600 and 1800 respectively(Figures 2(b) and 3(b)) There was no significant differencein the urinary levels of TAO between the controls and XPApatients lacking the diurnal variation in the younger agegroup (Figure 4(a)) In the older age group the urinary levelsof TAO in the XPA patients were reduced to half of those incontrols showing the dim peak at 1200 (Figure 4(b)) Thecorrelation among biomarkers could not be demonstratedstatistically

4 Discussion

Our preliminary study suggested the possible reduction inthe urinary levels of 6-SM in XPA patients [12] which wasconfirmed in both the younger and older age groups in thisanalysis and the presence of a dim peak is noteworthy (Fig-ure 1) Generally XPA patients should avoid sun exposure inorder to reduce the risk of ultraviolet hazard and such lessersunlight exposure may disturb the hypothalamic controlin melatonin metabolism Intriguingly XPA patients rarely

Oxidative Medicine and Cellular Longevity 3

000 600 1200 1800

XPANormal

0

5

10

15

20

25

(a)

000 600 1200 18000

5

10

15

20

25

XPANormal

(b)

Figure 2 Circadian rhythm of urinary levels of 8-hydroxy-21015840-deoxyguanosine (8-OHdG) (ngmgCre) in younger age group (a)and older age group (b) Solid and dotted lines denote values ofpatients with xeroderma pigmentosum groupA (XPA) and controlsrespectively

show circadian rhythm disturbances andor sleep disordersexcept excessive daytime drowsiness [12] As well as thereduced urinary excretion of 6-SM the increase of urinaryoxidative stress markers in aged XPA patients which wassuggested by our previous study in fewer subjects [8] was alsoconfirmed in the older age group Furthermore the increasedurinary secretions of 8-OHdG and HEL demonstrated thecircadian rhythm with the robust peak (Figures 2(b) and3(b)) in association with the reduced TAO (Figure 4(b))As mentioned above the XPA patients show various neu-rological disorders [1] and the aged ones tend to sufferfrom respiratory disturbance due to laryngeal dystonia vocalcord paralysis or sleep apnea [15ndash17] Needless to say theprogression of neurodegeneration andor respiratory failurecan disturb the redox control in the whole body but thereduction of melatonin secretion occurring even in theyounger age group (Figure 1(a)) may also precipitate theoxidative stress Accordingly we strongly speculate that theadministration of exogenous melatonin may possibly correctits disturbed metabolism alter or improve alertness andorprevent the exacerbation of oxidative stress

Oxygen and circadian rhythmicity are essential in amyriad of physiological processes to maintain homeostasisfrom blood pressure and sleepwake cycles down to cellularsignaling pathways that play critical roles in health anddisease [13] It is speculated reviewing several papers that

000 600 1200 1800050100150200250300350

XPANormal

(a)

000 600 1200 1800

XPANormal

050100150200250300350

(b)

Figure 3 Circadian rhythm of urinary levels of hexanoyl-lysine(HEL) (pmolmgCre) in younger age group (a) and older age group(b) Solid and dotted lines denote values of patients with xerodermapigmentosum group A (XPA) and controls respectively

the concentrations of many antioxidant enzymes such assuperoxide mutase have a morning peak while the occur-rence of lipid peroxidation has an evening peak like thepeak at 1800 in the urinary levels of HEL in the older agegroup of XPA patients On the other hand urinary markersof nucleic acid oxidation did not have diurnal variation inhealthy subjects [18] Similarly in this analysis the controlsin both the younger and older age groups did not show anycircadian rhythms in the urinary levels of 8-OHdG HELor TAO (Figures 2 3 and 4) It is possible that the diurnalvariation may be exaggerated in shift workers [19] andorpatients with neurological disorders like XPA In additionthe circadian clock plays an important role in the determi-nation of strengths of cellular responses to DNA damageand may subsequently influence the NER [20] AccordinglyXPA patients have the potential of demonstrating a robustdiurnal variation of biomarkers related to oxidative stressbecause NER is genetically damaged oxidative stress maybe augmented in XPA [8] and melatonin metabolism wasdisturbed [12]

Unfortunately long-lasting therapies have not beenestablished for neurological disorders in the XPA patientsWe tried the treatment with low-dose levodopa for laryngealdystonia providing the temporary improvement of dystoniaand hand tremor [15] Melatonin is remarkably functionallydiverse with actions as a free radical scavenger and


000 600 1200 18000

500100015002000250030003500400045005000

XPANormal

(a)

000 600 1200 18000

500100015002000250030003500400045005000

XPANormal

(b)

Figure 4 Circadian rhythm of urinary levels of total antioxidantpower (TAO) (120583M) in younger age group (a) and older age group(b) Solid and dotted lines denote values of patients with xerodermapigmentosum group A (XPA) and controls respectively

antioxidant circadian rhythm regulator anti-inflammatoryand immunoregulating molecule [9] The diseases havingboth the circadian rhythm disturbance and oxidativestress are likely to benefit from therapeutic agents with thecombination of circadian rhythm-resynchronizing propertiesand antioxidant actions Clinical trials of melatonin havebeen performed for sleep problems in children withneurodevelopmental disorders resulting in the partialamelioration of problems without adverse events [21 22]In Japan we are also proceeding with a clinical trial ofmelatonin for sleep problems in autism spectrum disordersand other clinical trials using melatonin are feasible Westrongly believe that the clinical trial of melatonin should beconsidered in XPA patients and we are preparing the trial

Competing Interests

The authors declare that they have no competing interests

References

[1] K H Kraemer N J Patronas R Schiffmann B P BrooksD Tamura and J J DiGiovanna ldquoXeroderma pigmento-sum trichothiodystrophy and Cockayne syndrome a complexgenotype-phenotype relationshiprdquo Neuroscience vol 145 no 4pp 1388ndash1396 2007

[2] C Nishigori S-I Moriwaki H Takebe T Tanaka and SImamura ldquoGene alterations and clinical characteristics of xero-derma pigmentosum group A patients in Japanrdquo Archives ofDermatology vol 130 no 2 pp 191ndash197 1994

[3] M Hayashi ldquoOxidative stress in developmental brain disor-dersrdquo Neuropathology vol 29 no 1 pp 1ndash8 2009

[4] B Halliwell ldquoOxidative stress and neurodegeneration whereare we nowrdquo Journal of Neurochemistry vol 97 no 6 pp 1634ndash1658 2006

[5] K Ozaki N Sanjo K Ishikawa et al ldquoElevation of 8-hydroxy-21015840-deoxyguanosine in the cerebrospinal fluid of three patientswith superficial siderosisrdquoNeurology and Clinical Neurosciencevol 3 no 3 pp 108ndash110 2015

[6] R Miyata M Hayashi N Tanuma K Shioda R Fukatsuand S Mizutani ldquoOxidative stress in neurodegeneration indentatorubral-pallidoluysian atrophyrdquo Journal of the Neurologi-cal Sciences vol 264 no 1-2 pp 133ndash139 2008

[7] M Hayashi S Araki J Kohyama K Shioda and R FukatsuldquoOxidative nucleotide damage and superoxide dismutaseexpression in the brains of xeroderma pigmentosum group Aand Cockayne syndromerdquo Brain and Development vol 27 no 1pp 34ndash38 2005

[8] M Hayashi K R Miyata and N Tanuma ldquoOxidative stress indevelopmental brain disordersrdquo in Neurodegenerative DiseasesS I Ahmad Ed pp 278ndash299 Springer New York NY USA2012

[9] S R Pandi-Perumal A S Bahammam G M Brown etal ldquoMelatonin antioxidative defense therapeutical implica-tions for aging and neurodegenerative processesrdquoNeurotoxicityResearch vol 23 no 3 pp 267ndash300 2013

[10] B M Escribano A L Colın-Gonzalez A Santamarıa andI Tunez ldquoThe role of melatonin in multiple sclerosis hunt-ingtonrsquos disease and cerebral ischemiardquo CNS and NeurologicalDisordersmdashDrug Targets vol 13 no 6 pp 1096ndash1119 2014

[11] B Claustrat and J Leston ldquoMelatonin physiological effects inhumansrdquo Neurochirurgie vol 61 no 2-3 pp 77ndash84 2015

[12] Y Okoshi N Tanuma R Miyata and M Hayashi ldquoMelatoninalterations and brain acetylcholine lesions in sleep disorders inCockayne syndromerdquo Brain and Development vol 36 no 10pp 907ndash913 2014

[13] MWilkingMNdiaye HMukhtar andN Ahmad ldquoCircadianrhythm connections to oxidative stress implications for humanhealthrdquoAntioxidants and Redox Signaling vol 19 no 2 pp 192ndash208 2013

[14] MHayashi KNakajima RMiyata andN Tanuma ldquoThe com-bined pathological physiological and pharmacological exami-nations are useful to evaluate the hypothalamic and circadianrhythm disturbances in developmental brain disordersrdquo inNeuropathology New Research A Estevo and T Honrado Edspp 113ndash124 Nova Science New York NY USA 2012

[15] R Miyata T Sasaki M Hayashi S Araki M Shimohiraand J Kohyama ldquoLow-dose levodopa is effective for laryngealdystonia in xeroderma pigmentosum group Ardquo Brain andDevelopment vol 32 no 8 pp 685ndash687 2010

[16] A Muto A Matsui Y Saito et al ldquoLaryngeal dystonia inxeroderma pigmentosumrdquo Brain and Development vol 27 no8 pp 598ndash601 2005

[17] T Ohto N Iwasaki H Okubo K Shin and A Matsui ldquoLife-threatening vocal cord paralysis in a patient with group Axeroderma pigmentosumrdquo Pediatric Neurology vol 30 no 3pp 222ndash224 2004


[18] I S Grew V Cejvanovic K Broedbaek et al ldquoDiurnal variationof urinary markers of nucleic acid oxidationrdquo ScandinavianJournal of Clinical and Laboratory Investigation vol 74 no 4pp 336ndash343 2014

[19] B Faraut V Bayon and D Leger ldquoNeuroendocrine immuneand oxidative stress in shift workersrdquo Sleep Medicine Reviewsvol 17 no 6 pp 433ndash444 2013

[20] A Sancar L A Lindsey-Boltz T-H Kang J T Reardon JH Lee and N Ozturk ldquoCircadian clock control of the cellularresponse to DNA damagerdquo FEBS Letters vol 584 no 12 pp2618ndash2625 2010

[21] P Gringras C Gamble A P Jones et al ldquoMelatonin forsleep problems in children with neurodevelopmental disordersrandomised double masked placebo controlled trialrdquo BritishMedical Journal vol 345 Article ID e6664 2012

[22] B Wright D Sims S Smart et al ldquoMelatonin versus placeboin children with autism spectrum conditions and severe sleepproblems not amenable to behaviour management strategies arandomised controlled crossover trialrdquo Journal of Autism andDevelopmental Disorders vol 41 no 2 pp 175ndash184 2011

Submit your manuscripts athttpwwwhindawicom

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014


MEDIATORSINFLAMMATION

of


Behavioural Neurology

EndocrinologyInternational Journal of



Disease Markers


BioMed Research International

OncologyJournal of



Oxidative Medicine and Cellular Longevity


PPAR Research

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Immunology ResearchHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

ObesityJournal of



Computational and Mathematical Methods in Medicine

OphthalmologyJournal of


Diabetes ResearchJournal of



Research and TreatmentAIDS


Gastroenterology Research and Practice


Parkinsonrsquos Disease

Evidence-Based Complementary and Alternative Medicine

Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom


predominantly in CS patients suffering from the disturbedcircadian rhythms of sleep-wakefulness and body tempera-ture regulation [12]

Recently redox regulation andor oxidative stress hasbeen reported to have diurnal variation and the circadianrhythms of oxidative stress markers and antioxidant enzymeshave been examined in healthy subjects and patients withneurological disorders [13] Nevertheless the relationshipsin diurnal variation between melatonin and oxidative stressmarkers still remain to be investigated Herein we analyzedthe circadian rhythms of oxidative stress markers and mela-tonin metabolites in urine of patients with XPA

2 Materials and Methods

We analyzed the urine from 8 patients with geneticallyconfirmed XPA and 8 normal controls aged from 6 to 37years It is well known that melatonin secretion varies by ageThe levels of plasma melatonin and its urinary metabolitesare high in infancy and early children decline dramaticallyaround adolescence and keep reducing gradually in adultsand aged people [14]

Accordingly we divided both XPA patients and controlsinto younger and older age groups consisting of threesubjects each less than 15 years and five ones each equalto and more than 15 years respectively Urine sampleswere collected four times a day (at 000 0600 1200 and1800) All specimens were stored at minus80∘C in a deep freezeravoiding lights Consents were granted from all parentsof patients and child controls and adult controls Thisanalysis was approved by the Ethical Committee of TokyoMetropolitan Institute of Medical Science We measured theurinary concentrations of 6-sulfatoxymelatonin (6-SM) amain metabolite of melatonin a marker of oxidative DNAdamage 8-hydroxy-21015840-deoxyguanosine (8-OHdG) an earlystage marker of lipid peroxidation hexanoyl-lysine adduct(HEL) and total antioxidant power (TAO) respectively aspreviously reported [8 12] We used commercially availableenzyme-linked immunosorbent assay (ELISA) kits for 6-SM (GenWay Biotech CA USA) 8-OHdG and HEL (JapanInstitute for the Aging Shizuoka Japan) and TAO (OxfordBiomedical Research MI USA) respectively

The results were normalized to urine concentration ofcreatinine (Cre) except TAO Correlations among 6-SM 8-OHdG HEL and TAO at each time point were confirmed bySpearmanrsquos rank correlation coefficient

3 Results

The peak of urinary 6-SM was identified at 600 in theyounger and older age group of both controls and all XPApatients and the peak value was reduced by age (Figure 1)The XPA patients demonstrated a lower peak value whichwas approximately one-third and half of each of those incontrols The urinary levels of 8-OHdG were low and lackedthe diurnal variation in the younger age group in bothcontrols and XPA patients (Figure 2(a)) In the older agegroup the urinary levels of 8-OHdG were increased in

600 1200 18000000102030405060708090100

(ngmgC

re)

XPAControl

(a)

000 600 1200 1800

XPAControl

0102030405060708090100

(ngmgC

re)

(b)

Figure 1 Circadian rhythm of urinary levels of 6-sulfatoxymela-tonin (6-SM) (ngmgCre) in younger age group (a) and older agegroup (b) Solid and dotted lines denote values of patients withxeroderma pigmentosum group A (XPA) and controls respectively

the XPA patients but not in controls in which the robust peakwas identified at 600 (Figure 2(b))The urinary levels of HELwere low and lacked the diurnal variation in the younger agegroup in both controls and XPA patients (Figure 3(a)) In theolder age group the urinary levels of 8-OHdG and HEL wereincreased in the XPA patients but not in controls in whichthe robust peak was identified at 600 and 1800 respectively(Figures 2(b) and 3(b)) There was no significant differencein the urinary levels of TAO between the controls and XPApatients lacking the diurnal variation in the younger agegroup (Figure 4(a)) In the older age group the urinary levelsof TAO in the XPA patients were reduced to half of those incontrols showing the dim peak at 1200 (Figure 4(b)) Thecorrelation among biomarkers could not be demonstratedstatistically

4 Discussion

Our preliminary study suggested the possible reduction inthe urinary levels of 6-SM in XPA patients [12] which wasconfirmed in both the younger and older age groups in thisanalysis and the presence of a dim peak is noteworthy (Fig-ure 1) Generally XPA patients should avoid sun exposure inorder to reduce the risk of ultraviolet hazard and such lessersunlight exposure may disturb the hypothalamic controlin melatonin metabolism Intriguingly XPA patients rarely


000 600 1200 1800

XPANormal

0

5

10

15

20

25

(a)

000 600 1200 18000

5

10

15

20

25

XPANormal

(b)




000 600 1200 1800050100150200250300350

XPANormal

(a)

000 600 1200 1800

XPANormal

050100150200250300350

(b)





000 600 1200 18000

500100015002000250030003500400045005000

XPANormal

(a)

000 600 1200 18000

500100015002000250030003500400045005000

XPANormal

(b)



Competing Interests


References





























of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of

















000 600 1200 1800

XPANormal

0

5

10

15

20

25

(a)

000 600 1200 18000

5

10

15

20

25

XPANormal

(b)




000 600 1200 1800050100150200250300350

XPANormal

(a)

000 600 1200 1800

XPANormal

050100150200250300350

(b)





000 600 1200 18000

500100015002000250030003500400045005000

XPANormal

(a)

000 600 1200 18000

500100015002000250030003500400045005000

XPANormal

(b)



Competing Interests


References





























of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of

















000 600 1200 18000

500100015002000250030003500400045005000

XPANormal

(a)

000 600 1200 18000

500100015002000250030003500400045005000

XPANormal

(b)



Competing Interests


References





























of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of



























of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of
















research article circadian rhythms of oxidative stress

Documents