Psoriasis is a non-infectious, chronic inflammatory disease of the skin. This study aimed to explore the oxidative stress and stress induced protein changes in psoriasis and to analyse the possible interrelationship between these factors among psoriasis patients. This was a hospital-based case control study which included 50 cases of psoriasis and 50 healthy controls. Serum malondialdehyde was measured by thiobarbituric acid reactivity assay method. Protein carbonyl (PC) was measured by Levine’s method. Protein bound sialic acid (PBSA) was measured using modified Aminoff’s method using a spectrophotometer. Data analysis was done using SPSS software version 16.0. Our results showed significant elevation in the oxidant status (MDA, PC and PBSA) among the psoriasis cases compared to the controls. Multiple linear regression analysis showed a linear relationship between MDA, PBSA and duration of psoriasis. Our study provides evidence to increased ROS production, indicated by increased lipid peroxidation in serum and stress induced protein changes in psoriasis. The findings of our study also suggest that as the duration of psoriasis increases the level of oxidative stress also increases which is indicated by the increase in MDA and PBSA levels.

1. Running title: Oxidative stress in psoriasis
Evaluation of Oxidative Stress and Stress Induced Serum Protein Changes in Psoriasis
Evaluation of Oxidative Stress and Stress Induced Serum
Protein Changes in Psoriasis
*Ashok Vanangamudi1, Divya Ramanathan2
1Assistant Professor, Department of Biochemistry, Karpagam Faculty of Medical Sciences and Research, Coimbatore,
India-641032
2Assistant Professor, Department of Physiology, Karpagam Faculty of Medical Sciences and Research, Coimbatore.
Psoriasis is a non-infectious, chronic inflammatory disease of the skin. This study aimed to
explore the oxidative stress and stress induced protein changes in psoriasis and to analyze the
possible interrelationship between these factors among psoriasis patients. This was a hospital-
based case control study which included 50 cases of psoriasis and 50 healthy controls. Serum
malondialdehyde was measured by thiobarbituric acid reactivity assay method. Protein carbonyl
(PC) was measured by Levine’s method. Protein bound sialic acid (PBSA) was measured using
modified Aminoff’s method using a spectrophotometer. Data analysis was done using SPSS
software version 16.0. Our results showed significant elevation in the oxidant status (MDA, PC
and PBSA) among the psoriasis cases compared to the controls. Multiple linear regression
analysis showed a linear relationship between MDA, PBSA and duration of psoriasis. Our study
provides evidence to increased ROS production, indicated by increased lipid peroxidation in
serum and stress induced protein changes in psoriasis. The findings of our study also suggest
that as the duration of psoriasis increases the level of oxidative stress also increases which is
indicated by the increase in MDA and PBSA levels.
Keywords: oxidative stress, malondialdehyde, Protein carbonyl, PBSA
INTRODUCTION
Psoriasis is a disorder of the skin characterized by
inflammation of the skin and hyperproliferation of
keratinocytes. The most commonly affected are young or
middle-aged adults (Camp RDR, 1998). Around 2% of the
general population worldwide are affected with psoriasis
(Wolters M et al, 2005). The prevalence of psoriasis in
Indian population varies from 0.4% - 2.4% (Dogra M et al,
2010).
The causes for psoriasis are genetic factor, trauma, skin
infection, drugs, emotional stress, alcohol and smoking.
The generation of reactive oxygen species (ROS) from
neutrophils, keratinocytes and fibroblasts can lead to
neutrophil activation and they have major role in the
development of psoriasis (Vivian S 2013).
Oxidative stress is due to excessive production of reactive
oxygen species (ROS) or defect in its removal
mechanisms. The free radicals generated by oxidative
stress causes oxidation of polyunsaturated fatty acids in
cell membrane and results in the generation of lipid
peroxidation products like malondialdehyde (MDA). In
psoriatic patients, the cell membrane of skin cells has
increased arachidonic acid, which is the substrate for
production of malondialdehyde. MDA is used as a
biomarker of oxidative stress and lipid peroxidation
(Vijaykumar M et al 2014, Sikar A. 2012, Trouba K. 2002).
The ROS can damage the proteins or induce chemical
modification of amino acids in the proteins during the
process of oxidative stress. Carbonyl groups are
introduced into proteins by reaction with ROS produced
during lipid peroxidation. The carbonyl content of serum
proteins is used as a biomarker of protein oxidation
(Stadtman E,1998).
*Corresponding Author: Ashok Vanangamudi, Assistant
Professor, Department of Biochemistry, Karpagam faculty
of medical sciences and research, Coimbatore, India-
641032. E-mail: dr.ashokmbbs1986@yahoo.com, Tel:
+919159572499, Co-Author Tel: +919074202158 Email:
divyaashok47@yahoo.in
Research Article
Vol. 5(1), pp. 075-079, June, 2019. © www.premierpublishers.org, ISSN: 0524-0557
International Research Journal of Biochemistry and Biotechnology

2. Running title: Oxidative stress in psoriasis
Evaluation of Oxidative Stress and Stress Induced Serum Protein Changes in Psoriasis
Vanangamudi and Ramanathan 076
Sialic acid is the terminal carbohydrate in the glycan
moiety of glycoproteins. Sialic acid is a N-acetylated
derivative of neuraminic acid which increases during injury
and inflammation (Devatdarova M, 1968). According to a
study by Rajapppa M et al (2016) serum levels of oxidative
stress and inflammatory markers like highly sensitive C-
reactive protein, total sialic acid, protein bound sialic acid
were significantly higher in psoriasis vulgaris patients as
compared to the normal controls. This shows that oxidative
stress and inflammatory markers like serum total sialic
acid and protein bound sialic acid are associated with the
pathogenesis of psoriasis.
The objectives of the study were
1. To analyze oxidative stress in patients with psoriasis
and compare it with normal controls.
2. To estimate oxidative stress induced protein carbonyl
content (PC) and protein bound sialic acid (PBSA) in
psoriasis and compare it with controls.
3. To find the correlation between oxidative stress, protein
carbonyls and protein bound sialic acid in patients with
psoriasis.
MATERIALS AND METHODS
This was a hospital-based case control study. This study
was conducted after getting approval by the Institutional
Ethics Committee Sri Manakula Vinayagar Medical
College and Hospital, Pondicherry. The duration of study
was two years 2013-2015.The sample size was 100 which
included 50 cases of psoriasis and 50 healthy controls.
Inclusion criteria
Cases: Patients diagnosed to have psoriasis in the
Department of Dermatology.
Controls: Normal healthy controls, non-psoriatric patients
attending dermatology outpatient department.
Exclusion criteria
1. Psoriasis patients with systemic illness like diabetes
mellitus, renal failure, coronary artery disease and
history of recent drug intake for treatment.
2. Any subjects with systemic infections and chronic
inflammatory conditions.
3. Any subjects who were not willing to give informed
consent.
Biochemical analysis
Serum total protein was estimated by Biuret method
(Doumas BT. 1981). Serum MDA was estimated by
thiobarbituric acid reactivity assay method (Satok K 1978).
12 Serum protein carbonyl was estimated by modified
Levine’s method (Chakraborthy H .2000). Serum protein
bound sialic acid was estimated by modified Aminoff’s
method (Aminoff D 1961).
Statistical Analysis
The data was presented as mean ± standard deviation
(mean ± SD). Student t test was used to compare the
various parameters between psoriasis subjects and
controls. Multiple linear regression analysis was done to
analyze the relationship between various parameters of
oxidative stress. P value of less than 0.05 was statistically
significant.
RESULTS
The comparison of various baseline characteristics of the
study groups was shown in Table1. All data were
represented as mean ± standard deviation. In our study it
was observed that the parameter of oxidative stress, MDA
was elevated (p<0.001) in psoriatic patients as compared
to controls (Table2). Also, the stress induced serum
protein changes, PC and PBSA concentrations were high
(p<0.001) in the patients with psoriasis as compared to
controls (Table2).
Regression analysis showed a linear relationship between
MDA and the duration of psoriasis (Table 3 and Figure 1).
Linear regression analysis showed a linear relationship
between PBSA and the duration of psoriasis (Table 3 and
Figure 2).
DISCUSSION
The skin is a vulnerable target for oxidative injury by free
radicals, as it is continuously exposed to UV radiation and
other environmental stresses which generate reactive
oxygen species (Dipali P et al 2009). In normal cells, there
will be a balance between oxidative damage and
protection by antioxidant protections. However inadequate
antioxidant protection mechanisms or excess free radical
production generates a condition known as oxidative
stress (Trouba K et al 2002).
Psoriasis is a chronic inflammatory disorder of the skin
which is characterized by increased proliferation of
keratinocytes and inflammation in the epidermis and
dermis (Young CN et al 2008). Various environmental and
genetic factors, as well as intracellular and intercellular
mediators, are found to play an important role in the
pathogenesis of psoriasis (Myers WA et al 2006).
Although there have been extensive studies (Jyothi RS et
al 2011, Zhou Q et al 2009, Mahmoud Y et al 2013) on the
role of oxidants and antioxidants levels in psoriasis, their
role in the etiopathogenesis of psoriasis remains
controversial. It has been suggested that ROS production
may play a vital role in the pathogenesis of psoriasis
through mechanisms like activation of Nuclear factor-kB
(NF-kB), generation of cytokines, modulation of signaling
pathways and activation of peroxisome proliferator-
activated receptors.

3. Running title: Oxidative stress in psoriasis
Evaluation of Oxidative Stress and Stress Induced Serum Protein Changes in Psoriasis
Int. Res. J. Biochem. Biotechnol. 077
Our study showed significant difference in the oxidant
status between the psoriasis cases and controls. Oxidant
status in psoriasis was assessed by the estimation of
serum malondialdehyde, protein carbonyl and protein
bound sialic acid. In the present study, serum MDA levels
were increased in psoriasis patients when compared to
normal controls (p<0.001). These findings are in
correlation with the findings of Dipali P et al (2009) and
Jyothi RS et al (2011).
Protein carbonyl content is the biomarker of oxidative
protein damage. A study by VV Barygina et al (2013)
showed that protein carbonyl was increased in patients
with psoriasis compared to the control group. In our study
the serum PC were elevated in patients with psoriasis as
compared to the controls.
Several studies have shown the relation between oxidative
stress and the alteration in sialylation of proteins.
Increased sialic acid concentrations have been reported
during inflammatory processes in plasma and serum
(Nanetti L et al 2008, Ajit Varki 2008). In our study serum
protein-bound sialic acid was increased in psoriasis
patients as compared to the controls.
Multiple linear regression analysis showed a correlation
between MDA and duration of psoriasis. Similarly, PBSA
was found to be correlated with the duration of psoriasis.
This indicates that the level of oxidative stress increases
with the duration of psoriasis.
The processes involved in the etiopathogenesis of
psoriasis are complex which involves ROS production and
free radical damage. Our observation supports the
concept that oxidative damage plays an important role in
the inflammatory response and etiopathogenesis of
psoriasis.
CONCLUSION
The present study provides evidence to increased ROS
production, which is indicated by increased production of
malondialdehyde in serum and stress induced protein
changes in psoriasis. The findings of our study also
suggest that the level of oxidative stress increases with the
duration of psoriasis. Moreover, dietary supplementation
of natural antioxidant vitamins may be considered as a
therapeutic approach to prevent the cell damage by free
radicals.
Declaration of conflict of interest: None.
REFERENCES
Ajit Varki. (2008). Sialic acids in human health and
disease. Trends Mol Med. 14(8):351–360.
Aminoff D. (1961). Methods for the quantitative estimation
of neuraminic acid and their application to hydrosylates
of sialomucoids. Biochem J. 82:384-92.
Camp RDR: Psoriasis In. Rook A, Wilkinson DS, Ebling
FJG (eds) (1998). Rook’s Text Book of Dermatology.
6th ed. New Jersy: Blackwell publishers; p.1589-1592.
Chakraborty H, Ray N. (2000) Lipid peroxidation
associated protein damage in rat brain crude
synaptosomal fraction mediated by iron and ascorbate.
Neurochem Int J. 39:311-17.
Dalle-Donne I, Giustarini D, Colombo R, Rossi R, Milzani
A. (2003) Protein carbonylation in human diseases.
Trends Mol Med. 9(4):169-176.
Devatdarova M. (1968). Sialic acid levels in the serum of
healthy persons and patients with psoriasis. Vestn
Dermatol Venerol. 42(8):43-46.
Dipali P Kadam, Adinath N Suryakar, Rajesh D Ankush,
Charushila Y Kadam, Kishor H Deshpande. (2010).
Role of Oxidative Stress in Various Stages of Psoriasis.
Ind J Clin Biochem. 25(4):388–392.
Dogra S, Yadav S. (2010). Psoriasis in India: prevalence
and pattern. Ind J Dermatol Venerol Leprol. 76(6):595-
601.
Doumas BT. (1981). A candidate reference method for
determination of total protein in serum. Clin Chem Acta.
27:1642-1650.
Jyothi RS, Govindswamy KS, Gurupadappa K. (2011)
Psoriasis: an oxidative stress condition. J Clin Diagn
Res. 5(2):252-253.
Mahmoud Y, Eman N, Najlaa K, Rowida A, Mohamad N.
(2013). Role of Oxidative Stress in Psoriasis: An
Evaluation Study. J Am Sci. 9(8):151-155.
Myers WA, Gottlieb AB, Mease P. (2006). Psoriasis and
psoriatic arthritis: clinical features and disease
mechanisms. Clin Dermatol. 24:438–447.
Nanetti L, Vignini A, Raffaelli F. (2008). Sialic acid and
sialidase activity in acute stroke. Disease markers.
28:167-173.
Rajappa M, Shanmugam R, Munisamy M, Chandrashekar
L, Rajendiran KS, Thappa DM. (2016). Effect of
antipsoriatic therapy on oxidative stress index and sialic
acid levels in patients with psoriasis. Int J Dermatol.
55(8):422-430.
Satok K. (1978). Serum lipid peroxide in cerebrovascular
disorders determined by a new colorimetric method.
Clin Chim Acta. 90(1):37-43.
Sikar Akturk A, Ozdogan HK, Bayramgurler D, Çekmen
MB, Bilen N, Kıran R. (2012). Nitric oxide and
malondialdehyde levels in plasma and tissue of
psoriasis patients. J Eur Acad Dermatol Venereol.
26(7):833-837.
Stadtman E, Berlett B. Reactive oxygen mediated protein
oxidation in ageing and disease. (1998). Drug Metab
Rev. 30:225-43.
Trouba K, Hamadeh H, Amin R, Germolec D. (2002).
Oxidative stress and psoriasis. Antioxid Redox Signal.
4(4):665-73.
Vijaykumar M Pujari, Shankargouda Ireddy Inderraj
Itagi, and Siddesh Kumar H. (2014). The serum levels
of malondialdehyde, vitamin E and erythrocyte catalase
a ctivity in psoriasis patients. J Clin Diagn Res.
8(11):14-16.

4. Running title: Oxidative stress in psoriasis
Evaluation of Oxidative Stress and Stress Induced Serum Protein Changes in Psoriasis
Vanangamudi and Ramanathan 078
Vivian S, Krishna M. (2013). Potential role of oxidative
stress and antioxidant deficiency in pathogenesis of
psoriasis. Int J Pharm Bio Sci. 4(3):1039-1044.
VV Barygina, Becatti M, Soldi G, Prignano F, Lotti T, Nassi
P , Wright D , Taddei N , Fiorillo C. (2013). Altered redox
status in the blood of psoriatic patients: involvement of
NADPH oxidase and role of anti-TNF-α therapy. Redox
Rep. 18(3):100-106.
Wolters M. (2005). Diet and psoriasis: Experimental data
and clinical evidence. Br J Dermatol. 153:706-14.
Young CN, Koepke JI, Terlecky LJ, Borkin M, Boyd S,
Terlecky SR. (2008). Reactive oxygen species in tumor
necrosis factor α activated primary human
keratinocytes: implications for psoriasis and
inflammatory skin disease. J Invest Dermatol. 128(11):
2606–2614.
Zhou Q, Mrowietz U, Rostami-Yazdi M. (2009). Oxidative
stress in the pathogenesis of psoriasis. Free Radic Biol
Med. 47:891–905.
APPENDIX
Table 1: Comparison of baseline characteristics (mean ± standard deviation) in patients with psoriasis and controls
Parameters Cases(n=50) Controls(n=50) P value
Age (years) 41.20 ±9.21 41.56 ±8.99 0.82
Height(m) 1.48 ±0.08 1.49 ±0.07 0.60
Weight (kg) 60.22 ±7.96 59.80 ±8.83 0.83
BMI (kg/m2) 27.51 ±3.39 27.19 ±4.23 0.68
Systolic BP (mmHg) 116.96 ± 6.54 114.88 ±4.14 0.66
Diastolic BP (mmHg) 71.04 ±7.01 69.52 ±6.86 0.27
Pulse rate (beats/min) 76.16 ±7.01 75.70 ±6.58 0.72
Serum Total protein (g/dl) 7.18 ± 0.51 7.02 ±0.51 0.11
Duration of psoriasis (years) 5.02 ±2.55 - -
Data are presented as Mean ±SD.*P value ≤0.05 is statistically significant. Independent student t test
was used to analyze the data. BMI=Body mass index, BP=Blood pressure.
Table 2: Comparison of oxidative stress parameters (mean ± standard deviation) in patients with psoriasis and controls
Parameters Cases(n=50) Controls(n=50) P value
Serum MDA (µmoles/L) 6.31±2.68 3.65±1.48 <0.001*
Serum PC (µg/mg of protein) 2.88 ±0.75 2.43 ±0.35 <0.001*
Serum PBSA (nmol/mg of protein) 17.82 ±8.33 10.41±3.55 <0.001*
Data are presented as Mean ±SD.*P value ≤0.05 is statistically significant. Independent student t test was used to analyze
the data. MDA=Malondialdehyde, PC=Protein carbonyl, PBSA=Protein bound sialic acid.
Table 3: Linear regression analysis to find the effect of duration of psoriasis on parameters of oxidative stress
Independent Nonstandardized coefficients Standardized coefficients P value
Variables B value β
MDA 0.319 0.303 0.03*
PC -0.060 -0.018 0.90
PBSA 1.044 0.320 0.02*
* p<0.05 is considered statistically significant. MDA=Malondialdehyde, PC=Protein carbonyl, PBSA=Protein bound sialic
acid.

5. Running title: Oxidative stress in psoriasis
Evaluation of Oxidative Stress and Stress Induced Serum Protein Changes in Psoriasis
Int. Res. J. Biochem. Biotechnol. 079
Figure 1: Linear regression analysis between duration of psoriasis and MDA levels among the cases
Figure 2: Linear regression analysis between duration of psoriasis and Protein bound sialic acid (PBSA) levels among
the cases
Accepted 10 May 2019
Citation: Vanangamudi A, Ramanathan D (2019). Evaluation of Oxidative Stress and Stress Induced Serum Protein
Changes in Psoriasis. International Research Journal of Biochemistry and Biotechnology, 5(1): 075-079.
Copyright: © 2019 Vanangamudi and Ramanathan. This is an open-access article distributed under the terms of the
Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium,
provided the original author and source are cited.