Toryila J.E, Adelaiye A.B. Achie L.N
Human Physiology Department, Faculty of Medicine, ABU Zaria.
Amadi K, Odeh S.A
Human Physiology Department, Faculty of Medical Sciences Unijos.
BACKGROUND: It is estimated that 38% of all women worldwide between the ages of 15 – 40 years use combined oral contraceptives, which now differ significantly in formula and concentrations from previous ones. Duofem, a third generation combined oral contraceptive contains desogestrol. The formation is anticipated to give lower risks of thromboembolism, myocardial infarction, stroke and autoimmune diseases. This research priority included efforts to discover the effect of combined oral contraceptive (DUOFEM) on fibrinogen and interleukin-6 in female wistar rats.
METHOD: Forty (40) female wistar rats weighing 180-250 g were used for the study. They were divided into four groups of 10 rats each comprising 5 treated and 5 control rats. The treated rats received 0.6mg/kg body weight of COC intragastrically for 36, 48, 60 and 72 days. All groups were given fresh water at ad libitum daily for the period of the experiment. Interleukin-6 was determined using rat ELISA kit ( Karmiya Biomedical company, USA). Fibrinogen was estimated by Clauss Assay (Clauss, 1957)
RESULTS: DUOFEM reduced the serum levels of both fibrinogen and interleukin-6 in all the treated groups compared to controls (P<0.05). Lowest serum levels of fibrinogen and interleukin-6 was observed in group D (72 days). By lowering IL-6 and fibrinogen, estrogen can negatively suppressed the body’s immune response, triggering a predisposition to autoimmune and cardiovascular diseases.
Key words: Combined Oral Contraceptive, Fibrinogen, Interleukin-6
Contraception is an important health issue in preventive medicine because it protects women globally from the effects of unwanted pregnancy and allows them to integrate into society. Combined Oral Contraceptives (COCs) are currently among the most commonly used drugs in developed countries
Long-term use of combined oral contraceptives (COCs) and of hormone replacement therapy (HRT) have been linked to increased blood coagulation, increased risk of cardiovascular diseases and altered immune and inflammatory factors, suggesting an increased risk of chronic immune disorders with an inflammatory component, including cancer (WHO, 2009).
COCs have evolved through various modifications to reduce the dosages of the different hormonal
components to minimize the risk of thrombotic events, such as stroke. The type of oral contraceptives prescribed differs between countries, and both the type of oral contraceptive and the doses of estrogens and progesterone have changed between and within countries over time (Bulur et al, 2012). DUOFEM is an emergency contraceptive product that is designed to prevent pregnancy. It is intended for use by women from eighteen years up to menopause Interleukin-6 (IL-6) is a four-helical cytokine of 184 amino acids. The protein is synthesized by fibroblasts, monocytes, macrophages, T cells and endothelial cells. IL-6 synthesis and secretion is induced during inflammatory conditions such as upon stimulation of Toll-like receptor (TLR)-4 by lipopolysaccharide or upon stimulation of cells by IL-1 or tumor necrosis factor (TNF)-a (Dirk and Stefan, 2016) Interleukin-6 (IL-6) is a multifunctional cytokine which is involved in a broad spectrum of activities such as immune defense, hematopoiesis, and the acute phase response, as well as in the pathogenesis of multiple myeloma. IL-6 has been demonstrated to have a pivotal role in the pathogenesis of rheumatoid arthritis, Castleman’s disease and Crohn’s disease exemplified by the use of an anti-IL-6 biological therapy. IL-6 is also associated with the autoimmune disease systemic sclerosis and has been shown to be directly fibrotic. They are capable of mediating a complex array of pro- and anti-inflammatory effects. IL-6 produces C-Reactive Protein (CRP) which leads to cardiovascular risk (Subhadeep et al., 2008). Estrogen is able to decrease IL-6 expression by blocking the estroblast’s synthesis of IL-6 receptors (Subhadeep et al., 2008). . Straub et al. (2000) and Rachon et al. (2002) report decrease IL-6 level in menopausal women taking hormonal replacement therapy.
Fibrinogen is a key component of the inflammation and clotting pathways and an established risk factor for cardiovascular disease (CVD). Fibrinogen production is upregulated in response to cytokines released during inflammation, infection, neoplasia or tissue damage.(Ernst, 1993). Sex hormone balance is crucial in the regulation of inflammatory and immune responses, as estrogens play a role in enhancing immune function while androgens and progesterone have a suppressive function.
MATERIALS AND METHOD:
Forty (40) female wistar rats weighing 180-250 g were used for the study. They were divided into four groups of 10 rats each comprising 5 treated and 5 control rats. The treated rats received 0.013mg/kg body weight of COC intragastrically for 36, 48, 60 and 72 days. All groups were given fresh water at ad libitum daily for the period of the experiment. Interleukin-6 was determined using rat ELISA kit ( Karmiya Biomedical company, USA). Fibrinogen was estimated by Clauss Assay (Clauss, 1957).
DISCUSSION AND CONCLUSION
There was decrease fibrinogen levels in all the treated groups compared to the control. This finding differs from that of Eliana and Koni (2014), Peter. (2013) and Carol (2015) who reported increase in fibrinogen level in women taking COC. The finding also differ from that of Akhigbe et al. (2008) who found no significant change in fibrinogen level in female wistar rats treated with COC. Fibrinogen functions as a messenger molecule that coordinates and regulates the body response to inflammation. The association between increase in plasma fibrinogen and thrombosis and the risk of myocardial infarction, atherosclerosis and other cardiovascular diseases are well established. Higher level of fibrinogen raises the risk of stroke (Abdalla et al. 2008).Low fibrinogen levels are associated with low risk of cardiovascular diseases.
There was a significant decrease in serum level of interleukin-6 (IL-6). Estrogen is able to decrease IL-6 expression by blocking the estroblast’s synthesis of IL-6 receptors (Jean et al., 1992). IL-6 produces C – reactive protein (CRP) which leads to cardiovascular risk. Experimental studies have shown strong correlations between the risk of cardiovascular diseases and inflammatory markers such as CRP and tissue neurosis factor-a (TNF a). IL-6 is a pleotropic cytokine which stimulates B-lymphocyte and T-lymphocyte differentiation, and activates macrophages and natural killer cells (NK). Interleukin 6 (IL-6), promptly and transiently produced in response to infections and tissue injuries, contributes to host defense through the stimulation of acute phase responses, hematopoiesis, and immune reactions. IL-6 has been demonstrated to have a pivotal role in the pathogenesis of rheumatoid arthritis, Castleman’s disease and Crohn’s disease exemplified by the use of an anti-IL-6 biological therapy. However, IL-6 is also associated with the autoimmune disease systemic sclerosis and has been shown to be directly fibrotic (Rachon et al.2002).
The inflammatory cytokine interleukin-6 (IL-6) is a main regulator of fibrinogen synthesis. Interleukin 6 (IL-6), promptly and transiently produced in response to infections and tissue injuries, contributes to host defense through the stimulation of acute phase responses, hematopoiesis, and immune reactions. Fibrinogen is a key component of the inflammation and clotting pathways and an established risk factor for cardiovascular disease. By lowering IL-6 and fibrinogen, estrogen can negatively suppress the body’s immune response, triggering a predisposition to autoimmune and cardiovascular diseases.
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