Free «Effects of Academic Stress on Secretory IGA» Essay Sample

Introduction

Stress can affect daily life in many different ways. It can also affect the immune system. Animal studies have reported a link between stress and infections (Mestecky 2005). A study conducted on medical students showed that specific components of immunity declined during exams. Stress reduces the number of natural killer cells and lowers level of interferon gamma production. Studies have shown that even low amounts of acute stress can adversely affect specific component of the immune response that can recover (Svebek 1997). However, longer stressful periods affect multiple components of the immune response making it hard to recover.

Production of IgA decreases during episodes of acute stress such as before an oral presentation (Kluger et al. 1996). IgA are either produced by plasma cells located in the lamina propiria in the mucus membrane of tissues or in the connective glands. A molecule of secretory IgA has diametric immunoglobulin A, which has J chain and a glycoprotein binding it covalently to the J chain (Mackinnon & Hooper 1994). The glycol protein helps in stabilizing the secretory IgA molecule. In addition, it helps in ensuring that digestive enzymes or bacteria do not affect it while it is in the secretory fluid environment. The main function of secretory IgA is boosting the immunity of the body. It helps in preventing bacteria from establishing colonies in the mucus membrane (Perera, Sabin & Nelson, 1998). In addition, it activates lacto-ferrin and lacto peroxidase so that they can fight any pathogens attacking the body. Secretory IgA also neutralizes any toxins that are produced by pathogens attacking the body (Hucklebridgw 2002). In case any pathogenic viruses try to penetrate into the epithelial cells of the body, it is the duty of the secretory IgA to ensure that all these viruses are neutralized.

There is substantial evidence that psychological stress from the environment affects the immune system in humans (Gorski 2002). Research from scientists has proved that stress causes the production of adrenaline rush in flight or fight response. Flight and fight response triggers the brain, making a person feel that he/she is in danger. Cortisol levels in the body increase in an attempt of making a person gain energy. The rate of heart beat increases in order to help the heart to pump blood to major muscles (McClelland, Ross & Patel, 1985). It helps a person to run or fight in an attempt of escaping the danger. Body immune system is reduced since immune functions are not necessary when the body is in fight of flight mode. The non-essential functions of the body are also shut down while the digestive system is slowed down (Dean 1994). Academic stress is caused by many factors. One of the causes of academic stress is the performance of students. Teachers and parents may expect a child to perform better than the actual ability of this child (Hubbard & Workman 1997). In addition, teachers may give students a lot of work and expect them to complete this work within a short time (Rao 2008). Moreover, a student may experience stress when he/she is forced by peers to engage in activities that may be contrary to his/her personal beliefs.

Academic stress can cause a reduction in the levels of secretory IgA. This may cause the body to experience chronic dermatological conditions. In addition, students with low secretory IgA face the risk of contracting upper respiratory tract infections, asthma, candidiasis and food allergies (Mutton, Fillion, Tawadros & Tessier 1989). Secretory IgA is the most abundant Immunoglobulin in human saliva and  it plays a major role in the gastrointestinal tract by protecting it against pathogens from attaching and gaining entry to the mucosa (Burns 2004). Recent studies have established that intense physical exercise decreases sIgA, which can increase risk to infections (Gleeson 1999).

The aim of this project is to determine if stress in fourth year Immunology students similarly affects salivary IgA levels. The stressors were environmental and personal experiences. Samples were collected at the beginning of the semester and 5 days after the mid-semester test that occurred in the eighth week. During this time students were rating themselves as highly stressed. The hypothesis for this study was that high academic stress reduces the levels of secretory IgA in university students.

Methods

Materials

Rabbit antihuman IgA –Sigma USA, IgA form human colostrum – Sigma USA, Goat anti human IgA alkaline phosphatase conjugated antibody – Sigma USA, 4-nitrophenol – sigma USA, Dietholamine – Sigma USA, ELISA 96 well tray - Sarstedt Germany, salivettes - Sarstedt Germany, ELISA plate reader - mushkin ascent – Labsystems.

Population

The population for this study consisted of 14 fourth year Immunology students in Curtin University. The number of female students was 8 while the number of male students was 6. All participants were aged between 20-25 years. The race was mixed and it included Caucasians and Asians. Each individual recorded the stress scores considering the chart below. Every event was given its own stress score. There were no exclusion criteria. Participants were sampled for their stress score and IgA levels in 2 sessions. The first session was at the start of the semester and the second session was 5 days after the mid-semester test

Measurement of Stress Chart

Collection of saliva in both sessions obtained samples using the salivette recovery system. Participants drank 100mls of water rinsing their mouth as much as possible. A cotton swab form the salivette was placed in mouth of each participant for 2minutes. Participants were not allowed to swallow saliva during the test. The swab was then kept still and placed back into its salivette compartment. Salivette was centrifuged for 5 minutes @4000rpm.  The swab compartment was removed and discarded. However, the lid on the remaining tube was retained.

Frozen samples from the first session were kept at -80°C. After this, they were thawed to room temperature and placed in a 56°C water bath for 30 minutes. Later, they were centrifuged for 5 minutes @ 4000 rpm. 1 ml of the sample was alliquoted into a microfuge without disturbing any sediment at the bottom of the salivette tube. 12000g of the samples were later microfuged for 20 minutes. The souretant was then aluoted by avoiding disturbing the pellet at the bottom. Lastly, samples were stored at -20°C until used for testing in Elisa.

Discussion

In the beginning of week one the mean stress score in males was higher than the mean stress score in females. The results may indicate that the male students were affected more by the problems at their home than the way female students were affected. Statistics have shown that male students are affected by many problems for example alcohol abuse and this increases their level of stress (Svebek 1997). In addition, most male students like to be independent and this makes them to prefer looking for jobs that will make them meet their financial needs. It increases their stress levels because some of them are not able to meet their financial needs (Rao 2008). At the end of the eighth week, the stress levels of male students were also higher than that of female students. It may indicate that male students were affected by exam anxiety more than the female students were.

Exam anxiety is caused by many factors. One of the major factors is a student believing that he/she will perform poorly in an exam (Bjorkman 2007). In addition, a student may not be prepared well for the exam because of concentrating on other issues rather than education. Male students also engage in many sport activities while they are in school. Some of the activities that they engage in include football, rugby and baseball. In the process of engaging in school sporting activities, they may get injured and this will increase their stress levels (Kluger, Reintjes, Tewes & Schedlowski, 1996). The level of stress among students decreased at the end of the week eight compared to the first week. It may indicate that female students deal with schoolwork better compared to male students. The stress score on week two was higher than the stress score on week one because students were trying to adjust to the life of school. This may indicate they had spent a long time at home and it was therefore hard for them to adjust to the life learning. On week three, the stress levels of students reduced significantly because of adjusting to the academic life. The stress levels on week four started increasing because the students were preparing for the exams.

The total mean IgA was lower on weak eight compared to week one. These results conformed to the results arrived at by previous researchers. Researchers have established that stress causes the immunity functions of the body to slow down (Perera, Sabin & Nelson 1998). The body concentrates on producing adrenaline so that it can increase the energy of muscles to effect flight and fight response. Secretory IgA is involved in the first line of defense in the immunity of the body of all human beings. It mainly protects the body against infections brought about by yeast, food particles, parasites and imbalances between the gut and systemic illness (Mackinnon & Hooper 1994). Due to stress, the production of secretory IgA reduces because the body concentrates on other functions such as increasing the rate of heartbeat (Dienzer 2002).

Many scholars have used salivary secretory IgA as a stress marker. Studies have revealed that salivary secretory IgA is negatively correlated to self-perceived occupational stress which happens among nurses. A study was conducted on 56 nurses from the general ward and 106 nurses working on the emergency wards. The researchers used mental health Perceived Stress Scale and measured the concentrations of lysozme and IgA to determine the level of stress among the nurses working in the two departments (Koh et al. 1999). Results from this study revealed that the level of stress of the nurses in the emergency ward was higher than the level of stress of the nurses in the general ward. In addition, the level of secretion rates of secretory IgA was lower in emergency wards compared with the level of IgA secretion in general.

This study had several limitations. It did not consider whether it was necessary to exclude students with URTs. In addition, it did not include a control group in the experiment. It failed to consider whether perceived stress was a reliable value. In addition, the P values from this result were high showing that the results were not significant. The total P value of the mean stress was 0.46 while that of the female was 0.81. It shows that the null hypothesis should not be rejected and that the results were insignificant and not conclusive. In addition, the total mean IgA values were 0.56. The mean IgA values were 0.5 of females and 0.91 of males. It shows that the results were insignificant proving that the null hypothesis should not be rejected. A high P value suggests that academic stress does not affect the level of secretion of IgA. It shows that the data collected from this study should not be relied upon strongly while making conclusions. Another limitation of this study is that it used students taking immunology alone. It could consider collecting data from students doing different courses. In addition, it used data collected from one institution only. It could consider collecting data from students from different schools in different geographical locations.

Conclusion

To conclude, academic stress affects secretory IgA in university students.  From the study conducted on 14 students in Curtin University, it was clear that the level of academic stress was higher after exams than at the beginning of exams. Academic stress could be brought about by anxiety before exams. In addition, it could be caused by stress caused by lack of funds. The mean stress in males was higher than the stress in female students.  Male students engage in more stressful activities for example sports compared to female students. In addition, statistics show that male students engage more in drug abuse compared to female students and this contributes to their high stress levels. The results from this study could indicate that high academic stress contributes to low levels of secretory IgA. Stress hinders the immune response of the body. The mean IgA levels were higher on week one compared to week eight. It was mainly caused by the fact that academic stress on week one was lower compared to the academic stress on week eight. The mean IgA values of male students were higher compared to the mean values of female students because male students had more stress scores than female students.