Biol Trace Elem Res (2009) 127:102–108 DOI 10.1007/s12011-008-8230-8
Zinc, Manganese, Calcium, Copper, and Cadmium Level in Scalp Hair Samples of Schizophrenic Patients Md. Ashrafur Rahman & Mohammad Abul Kalam Azad & Md. Iqbal Hossain & M. M. A. Shalahuddin Qusar & Wasimul Bari & Farida Begum & S. M. Imamul Huq & Abul Hasnat
Received: 22 July 2008 / Accepted: 27 August 2008 / Published online: 23 September 2008 # Humana Press Inc. 2008
Abstract The purpose of the study was to determine the concentration of trace elements present in scalp hair sample of schizophrenic patients and to find out the relationship between trace elements level and nutritional status or socioeconomic factors. The study was conducted among 30 schizophrenic male patients and 30 healthy male volunteers. Patients were recruited from Bangabandhu Sheikh Mujib Medical University by random sampling. Hair trace element concentrations were determined by flame atomic absorption spectroscopy and analyzed by independent t test, Pearson’s correlation analysis, regression analysis, and analysis of variance (ANOVA). Mn, Zn, Ca, Cu, and Cd concentrations of schizophrenic patients were 3.8±2.31 μg/gm, 171.6±59.04 μg/gm, 396.23±157.83 μg/gm, 15.40±5.68 μg/gm, and 1.14±0.89 μg/gm of hair sample, while those of control subjects were 4.4±2.32 μg/gm, 199.16±27.85 μg/gm, 620.9±181.55 μg/gm, 12.23±4.56 μg/gm, and 0.47±0.32 μg/gm of hair sample, respectively. The hair concentration of Zn and Ca decreased significantly (p=0.024; p=0.000, respectively) and the concentration of Cu and Cd increased significantly (p=0.021; p=0.000, respectively) in schizophrenic patients while the concentration of Mn (p=0.321) remain unchanged. Socioeconomic data reveals that
M. A. Rahman : M. I. Hossain : F. Begum : A. Hasnat (*) Department of Clinical Pharmacy and Pharmacology, Faculty of Pharmacy, University of Dhaka, Dhaka 1000, Bangladesh e-mail:
[email protected] M. A. K. Azad Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Dhaka, Dhaka 1000, Bangladesh M. M. A. S. Qusar Department of Psychiatry, BSMMU, Dhaka, Bangladesh W. Bari Department of Statistics, University of Dhaka, Dhaka 1000, Bangladesh S. M. I. Huq Department of Soil, Water and Environment, University of Dhaka, Dhaka 1000, Bangladesh
Scalp Hair Samples of Schizophrenic Patients
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most of the patients were poor, middle-aged and divorced. Mean body mass indices (BMIs) of the control group (22.26±1.91 kg/m2) and the patient group (20.42±3.16 kg/m2) were within the normal range (18.5−25.0 kg/m2). Pearson’s correlation analysis suggested that only Ca concentration of patients had a significant positive correlation with the BMI (r= 0.597; p=0.000) which was further justified from the regression analysis (R2 =44%; t=3.59; p=0.002) and one-way ANOVA test (F=3.62; p=0.015). A significant decrease in the hair concentration of Zn and Ca as well as a significant increase in the hair concentration of Cu and Cd in schizophrenic patients than that of its control group was observed which may provide prognostic tool for the diagnosis and treatment of this disease. However, further work with larger population is suggested to examine the exact correlation between trace element level and the degree of disorder.
Introduction Schizophrenia is a psychiatric disorder affecting behavior, thinking, and emotion. The term schizophrenia comes from the Greek word schizo means split or divide and phrenos means mind [1]. This rarely treated psychiatric disorder primarily strikes the teenagers and young adults. Symptoms of schizophrenia as described by DSM-IV include delusion, hallucination, disorganized speech (e.g., frequent derailment or incoherence), grossly disorganized or catatonic behavior, and negative symptoms. Symptoms of schizophrenia provide a challenge to the physicians to differentiate it from other mental illness. Moreover, no clear picture of the etiology of this disorder has emerged. Alternatively, the pathophysiology of schizophrenia is not well understood, and the diagnosis of schizophrenia also remains cumbersome. It has been criticized as lacking in scientific validity or reliability [2]. For numerous metabolic and physiological processes in the human body, trace elements play a vital role [3]. Trace elements play a part in the synthesis and structural stabilization of both proteins and nucleic acids. They are also constituents of proteins and hormones. In addition, they are involved in the function of subcellular systems such as mitochondria as well as in membrane transport, nerve conduction, and muscle contraction. Some of them (Zn, Cu, Mn, and Se) act as antioxidants. Therefore, imbalances in the optimum levels of trace elements may adversely affect biological processes and are associated with many diseases [4]. Zinc plays an essential role in many aspects of metabolism including the activity of more than 300 enzymes, the structure of many proteins, and control of genetic expression [5, 6]. Zinc status affects basic processes of cell division, growth, differentiation, development, performance, and aging through its requirement not only for synthesis and repair of DNA, RNA, and protein but also for many other aspects of metabolism [7, 8]. Zinc is unevenly distributed within the brain particularly at high concentrations in the hippocampal mossy fiber system where it acts as a neuromodulator [9]. Interactions with inhibitory [10] and excitatory amino acid neurotransmitter are well known with Zn [11]. High concentration of zinc is neurotoxic [12]. Ca is also capable of inducing structural and cognitive deficits in schizophrenia, and it has been proposed that altered Ca signaling may constitute the central unifying molecular pathology in schizophrenia [13]. Lower level of Mn plays a significant role in the development of schizophrenia possibly by interfering the membrane stability [14]. No work with scalp hair samples of schizophrenic patients has been done to determine the concentrations of Zn, Mn, Ca, Cu, and Cd. Therefore, attempts were made to investigate the correlation between trace elements level and the degree of disorder, if any.
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Materials and Methods Thirty schizophrenic male patients (mean age 32±7 years) were randomly recruited from Bangabandhu Sheikh Mujib Medical University (BSMMU) by a specialist psychiatrist who was trained in Diagnostic and Statistical Manual of Psychiatric Disorders (Fourth Edition) and 30 education- and age-matched healthy male volunteers (mean age 31±7 years) were recruited purposively as control. The study subjects were briefed about the purpose of the study, and written consent was obtained from each of them. All subjects had to go through clinical examinations to find out existence of other diseases that might alter trace element level. Subjects also had to undergo a routine physical check-up including their organ activity, weight, nutritional condition, blood pressure, chest X-ray, and electrocardiogram. Hematocrit, blood urea, nitrogen, creatinine, glucose, and liver enzyme tests were also done for all subjects to find out their actual pathological condition. These subjects did not have diabetes, kidney failure, or other disease nor had they been treated with drugs, which can interfere with concentration of the elements (diuretics, antihypertensive drugs or mineral supplements, etc.). Patients who were mentally retarded and suffered from comorbid psychiatric disorders were also excluded from the study. Hair treated with artificial color was excluded from the study. Stainless-steel scissors were used to collect the hair sample. To avoid contamination handling, the cutting and transfer of hair samples were minimized and performed using plastic disposable forceps and disposable vinyl examination gloves. Sociodemographic data were also collected in a questionnaire form which contains important information including socioeconomic data, history of illness, family history, etc. Ethical approval was obtained from the BSMMU authority. Approximately 100 mg of hair samples were cut with scissor in the nape or occipital regions, as close to the scalp as possible. The distal ends of the hair were cut from the samples, leaving the specimens 3–5 cm in length. Samples were washed five times with high performance liquid chromatography grade water and then kept at 80°C for 24 h. Ten milligram of hair samples were measured and kept in a volumetric flask. Five milliliters of concentrated trace metal graded nitric acid (65%) was added to the hair samples kept in the volumetric flask. The flask was then kept at 120°C for 24 h. Two milliliters of perchloric acid was added and kept at 170°C until dryness. Finally, trace metal-graded concentrated nitric acid (65%) was added to make the final volume of 30 ml. Hair collection and analysis were carried out in dust-free environment. Analysis of the trace element was carried out using flame atomic absorption spectroscopy. Different concentrations (0.5, 1.0, 2.0, 5.0, and 10.0 mg/L) of trace elements were used for calibration of standard curves. Wavelengths were set at 422.7, 213.9, 279.5, 324.8, and 228.8 nm for calcium, zinc, manganese, copper, and cadmium, respectively. To verify the assay accuracy and to maintain quality, the standard solutions were run after every ten-test samples. A software package (Spactr AA software) was used to calculate the concentration of calcium, zinc, manganese, copper, and cadmium. Precaution for both collection and subsequent handling of hair was taken in order to avoid or minimize the contamination of trace elements. The results were expressed as mean ± SD. Differences between groups’ means was determined by independent sample t test. The significance level was set at p
