Sains Malaysiana 48(5)(2019): 1083–1095

http://dx.doi.org/10.17576/jsm-2019-4805-17

 

Oxidative Status in Bipolar Disorder (BD) and Its Correlation with Age, Gender and Body Mass Index (BMI)

(Status Oksidatif dalam Gangguan Bikutub dan Kaitannya dengan Umur, Jantina dan Indeks Jisim Tubuh)

 

JACLYN TAN AI CHIN, GEETHA GUNASEKARAN, MOHD HANAFI AHMAD DAMANHURI, CHAN LAI FONG, LOO JIANN LIN & GOON JO AAN*

 

Department of Biochemistry, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Center, Jalan Yaacob Latif, Bandar Tun Razak, 56000 Cheras, Kuala Lumpur, Federal Territory, Malaysia

 

Received: 23 August 2017/Accepted: 25 September 2018

 

ABSTRACT

Bipolar disorder (BD) is a chronic psychiatric illness which molecular foundations have yet to be elucidated. Oxidative stress appears to be a promising field of study to understand the formation of this disease in molecular level. The objective was to investigate the oxidative status of BD and its association with age, gender and body mass index (BMI). A cross-sectional study was conducted in a tertiary university hospital in Cheras, Malaysia on 55 patients with BD diagnosed using Mini Neuropsychiatric Interview (MINI). Peripheral markers of oxidative stress which include superoxide dismutase (SOD), glutathione peroxidise (GPx), catalase (CAT), malondialdehyde (MDA) and DNA damage were examined in subjects with BD (n=55) and compared to healthy controls (n=28). BD patients had significantly higher concentrations of MDA compared to healthy controls (p<0.001). Concentration of MDA was significantly higher in BD patients aged 40 and above compared to those aged 39 years and below (p<0.05). The concentration of MDA did not show significant difference between male and female BD patients, likewise between patients with BMI below and above 25. The percentage of normal DNA in healthy controls was significantly higher than that of BD patients (p<0.001), while percentage of mildly and severely damaged DNA in BD patients was significantly higher than that of healthy controls (mildly damaged: p<0.001; severely damaged: p<0.001). The severity of DNA damage in the BD patients was similar when compared between age, gender and BMI. SOD activity of BD patients was found to be comparable to that of healthy subjects as well as when compared between gender and age, but was significantly lower in subjects with BMI above 25 (p<0.05). CAT activity was significantly higher in BD patients compared to controls (p<0.001), while no significant difference was found when compared between gender, age and BMI. GPx activity did not show significant difference when compared between BD and healthy controls, gender, age and BMI. Multiple linear regression analysis showed that the percentage of normal DNA increases with age in BD patients (p<0.001), while the percentage of damaged DNA decreases with age (mildly damaged: p<0.002; severely damaged: p<0.001). Percentage of normal and damaged DNA are not significantly correlated with BMI, while all antioxidative enzymes (SOD, GPx, CAT) and MDA concentration did not show significant correlation with age and BMI. In conclusion, age and BMI are associated with the oxidative status of BD patients regardless of gender.

 

Keywords: Bipolar disorder; catalase; glutathione peroxidase; malondialdehyde; superoxide dismutase

 

ABSTRAK

Gangguan bikutub (BD) ialah sejenis penyakit psikiatrik kronik kerana asas kejadian molekulnya masih belum ditentukan. Tekanan oksidatif adalah bidang yang berpotensi dikaji dalam memahami kejadian penyakit ini pada peringkat molekul. Objektif kajian adalah untuk menentukan status oksidatif pada pesakit BD dan kaitannya dengan umur, jantina dan indeks jisim tubuh (BMI). Satu kajian keratan rentas telah dijalankan di sebuah hospital universiti pengajian tinggi di Cheras, Malaysia ke atas 55 pesakit BD yang didiagnos menggunakan Mini Neuropsychiatric Interview (MINI). Aktiviti enzim superoksida dismutase (SOD), glutation peroksida (GPx), katalase (CAT), kepekatan malondialdehid (MDA) dan kerosakan DNA dibandingkan antara subjek dengan BD (n=55) dan kawalan sihat (n=28). Pesakit BD mempunyai kepekatan MDA yang lebih tinggi secara signifikan berbanding kepada kawalan sihat (p<0.001). Kepekatan MDA adalah lebih tinggi bagi pesakit BD berumur 40 ke atas berbanding kepada yang berumur 39 dan ke bawah (p<0.05). Kepekatan MDA tidak menunjukan perbezaan yang signifikan apabila dibandingkan antara jantina, sama juga antara pesakit dengan BMI kurang atau lebih daripada 25. Peratus DNA normal pada kawalan sihat adalah lebih tinggi secara signifikan berbanding kepada pesakit BD (p<0.001), manakala peratus DNA rosak ringan dan rosak teruk pada pesakit BD adalah lebih tinggi secara signifikan berbanding kepada kawalan sihat (rosakan DNA ringan: p<0.001; kerosakan DNA teruk: p<0.001). Tahap kerosakan DNA dalam pesakit BD adalah lebih kurang sama apabila dibandingkan antara umur, jantina dan BMI. Aktiviti SOD pesakit BD adalah lebih kurang sama dengan subjek sihat dan apabila dibandingkan antara jantina dan umur, tetapi adalah lebih rendah secara signifikan pada subjek dengan BMI lebih daripada 25 (p<0.05). Aktiviti CAT adalah lebih tinggi secara signifikan dalam pesakit BD berbanding kumpulan kawalan (p<0.001), manakala tiada perbezaan signifikan antara jantina, umur dan BMI. Aktiviti GPx tidak menunjukkan perbezaan signifikan apabila dibandingkan antara pesakit BD dan subjek sihat, jantina, umur dan BMI. Analisis regresi linear berganda menunjukkan peratus DNA normal meningkat dengan umur (p<0.001), manakala peratus DNA rosak menurun dengan umur (kerosakan DNA ringan: p<0.002; kerosakan DNA teruk: p<0.001). Peratus DNA normal dan rosak tidak menunjukkan korelasi signifikan dengan BMI, manakala semua enzim oksidatif (SOD, GPx, CAT) dan kepekatan MDA tidak menunjukkan korelasi signifikan dengan umur dan BMI. Secara kesimpulannya, umur dan BMI adalah berkaitan dengan status oksidatif pesakit BD tanpa mengira jantina.  

 

Kata kunci: Gangguan bikutub; glutation peroksidase; katalase; malondialdehid; superoksida dismutase

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*Corresponding author; email: joaan@ukm.edu.my