Pathological effect of estrogen on some internal organs of albino mice

Introduction

Estrogens are biologically active hormones that are cholesterolderived and produced in human s and animals by the adrenal cortex, tests, ovaries and placenta.In plants, estrogenic compound s were also contained, (Hamid and Eskicioglu, 2012) [1] . Steroid estrogens may be identified as natural or synthetic hormone and may act as chemicals that inhibit endocrine. Estrogen is the predominant sex steroid hormone in females, crucial for the development and control of secondary sex characteristics; estrone, estradiol, and estriol are the three main endogenous estrogens that signify hormonal activity. Estradiol is the most potent and common of them. In all vertebrates, estrogens area synthesized (Ryan, 1982) [2] , and in some insects, (Mechoulam et al., 2005) [3] . An appearance of estrogen in both of these, (insects and vertebrates) indicates a deep evolutionary history of oestrogenic sex hormones. Estrone (E1), estradiol (E2) and estriol (E3) are the three main naturally occurring sources of estrogen in females. The form of estetrol (E4) is developed during pregnancy. Oestrogens circulate at lower concentrations in both men and women than androgens (Burger, 2002). Although oestrogen levels in males are substantially lower than those in females, oestrogen serves critical physiological functions (Lombardi et al., 2001) [5] . Estrogen, like other steroid hormones, permeate through the cell membrane and then attach to and activate oestrogen receptors (ERs) inside the cell. This process subsequently regulates the expression of multiple genes (Whitehead and Nussey, 2001) [6] . In addition, estrogens connect and activate receptors of estrogen and produce rapid-signal of membrane (mERs), (Soltysik, and Czekaj, 2013) [7] . Oestrogen is being synthesised from androgen by an enzyme known as aromatase, which is classified as CYP19A1 in the cytochrome P450 superfamily (Simpson et al., 2002) [8] . The biological process of action of estrogen involves binding to its receptor to trigger a tissue response, with two different estrogen receptor proteins (ERα and ERβ) exhibiting unique patterns of tissue expression (Mueller and Korach, 2001) [9] . This is refer that sex hormones have different effects in different kidney area (Kwan et al., 1996) [10] , and likely also in post UNX compensatory development. So efforts were undertaken to quantitatively assess the cross-sectional areas of the kidney zones, as well as glomerular volumes, glomerular counts, glomerular damage indicators, and glomerular injury mediators.

In an inflammatory bowel disease model. The oestrogen receptor (ER) is responsible for the inhibition of neutrophil aggregation in the intestine, as demonstrated by Harnish et al. (2004) [11] . The classic ER acts as atranscription factor based on ligand. Recent data suggests that signal transduction occurs by oestrogen receptors despite related to the regulation of transcriptional genes (Rajesh et al., 2005) [12] , also suspected that the non genomic effects of estrogen are accelerate by these receptors which is located in or near the plasma membrane (Kelly and Levin,2001Isolate the effects of genomic processes facilitated by the nuclear oestrogen receptors. Studies continually use 17-estradiol (E2) membrane-impermeable combines, such as E2 conjugated to BSA (E2-BSA) (Stevis et al., 1999) [14] . The present study has been aimed for investigating the effects of estrogen on the kidney, lung, liver, and intestine and heart tissues, in mice.

Materials and Methods

Two groups were established by dividing twenty adult Albino mice (male and female) at 21 days of age. An s/c injection of 0.04 mg/kg b.w. of oestrogen was given to the first group (G1), which included 10 mice (5 males and 5 females). The ten mice in the second group-five male and five femalewere given 0.1 ml of olive oil as a control group that received no treatment.

Results

Histopathological alterations in rats administered estrogen daily for six weeks after therapy. Liver: exhibits vacuolation of hepatic cells, characterized by enlarged nuclei and significantly dilated sinusoids containing inflammatory cells inside their lumens. Moreover, many micro granulomatous lesions originate by the accumulation of lymphocytes and macrophages inside the liver parenchyma (Figure 1, 2, 3).

Kidney:

The lesion is defined by the accumulation of a significant material in the renal tubule (Figure 4). Furthermore, there is desquamation of the epithelial lining cells inside the renal tubules, followed by vascular congestion and significant acute cellular degeneration, along with moderate interstitial mononuclear cell infiltration (Figure 5).

Lung: There was congestion of pulmonary vessels, thickening of inter alveolar septa due to congestion of the alveolar capillaries and infiltration of the neutrophils (Figure 6,7).

Intestine: There was diffuse necrosis of mucosa with shortening or loss of villi of small intestine Intestinal mucosa showed increase in number of goblet cells with increase amount of mucin seen in the lumen. Focal infiltration of inflammatory cells especially neutrophils with few free RBC, in lamina propria of mucosa were also seen (Fig 8). Therapeutic Intervention Estrogen is administered as a solution at a dosage of 0.04 mg per kg of body weight by subcutaneous injection.

Brain:

The cerebrum tissue slices exhibited significant dilatation and congestion of cerebral and meningeal blood vessels (Figure 9). Congestion of blood capillaries accompanied with perivascular and perineuronal edema. The cerebellum exhibited pyknosis of the nuclei in the granular layer cells of the folia, together with necrosis affecting a substantial proportion of those cells (Figure 10). Additionally, there is edema present between the granular and molecular layers, along with degeneration of several Purkinje cells and total breakdown of others.

Heart:

The histopathological examination of the heart revealed infiltration of inflammatory cells, mostly neutrophils, inside the muscle bundles (Figure 11).

Stomach:

The histopathological examination of the stomach revealed infiltration of inflammatory cells, mainly neutrophils (Figure 12).

Discussion

The present finding revealed different pathological lesions in the liver, kidney, lung and heart increasing its severity within 6 weeks post-treatment. This may represent the primary lesions of estrogen resulting from interactions with the estrogen receptor (ER) and/or the synthesis of catechol estrogen (CE) by an oxidative stress-mediated mechanism (Mobley and Brueggemeier, 2002) [15] . Specific bio molecules are destroyed under oxidative stress. These include (proteins, lipids and DNA), which is most important. Oxidative damage to DNA is important as it is not possible to synthesize entirely new molecules to repair the damage done, compared lipids. Oxidative stress may result in increased damage that identified in different pathological situation, such as carcinogenesis, chronic inflammation, cardiovascular disease and neurodegenerative disease (Olinski, et al., 2007) [16] . As with estrogens, the DNA damage is accelerated by stimulation of replication, thatexplain tumorigenesis result in DNA damage (Malins et al., 1993) [17] , and this consistent with (Du and Gebicki, 2002) [18] . Reports indicate that lipid peroxidation precedes protein oxidation, with growing data suggesting that proteins are the initial and, under some circumstances, the exclusive extranuclear targets of oxidative stress. Lipid hydroperoxides (LOOH), recognized as the earliest products of lipid peroxidation, may cause damage both in vitro and in vivo (Refsgaar et al., 2000) [19] . However, the pathological changes in the internal organs particularly kidney may be due to toxic effects of estrogen metabolites, this evidence was supported idea, (Liehr, and Roy, 1990) [20] , who found that metabolic activation of estrogens, specifically, The free production of radicals by metabolic redox cycling between the quinone and hydroquinone forms of DES or catecholestrogen metabolites is hypothesized to contribute to the onset of carcinogenesis before hormone receptor-mediated cell transformation and tumor proliferation. Free radicals are produced in vitro by metabolic redox cycling in the case of synthetic estrogen DES.In addition, the development of metabolic quinone, redox cycling, (Roy and Liehr 1992) [21] . In the case of steroid estrogens, Free radicals are generated by redox cycling between estrone-3,4-quinone and its equivalent hydroquinone during biochemical incubations and in cultured MCF-7 cells. In which this metabolic activity causes DNA single strand, breaks (Nutter et al., 1994) [22] . However, quinone metabolites may be formed and undergo metabolic redox cycling in vivo but they may be too unstable to be detected in vivo (Ball, and Knuppen,. 1980; Floyd, 1990) [23,24] , reported that kidneys are particularly vulnerable to free radical damage either induced by redox cycling of cat echol estrogen substrates as outhned in this study or induced by toxic chemicals as demonstrated by others. This proposed mechanism is also corroborated by the observed DNA single-strand breaks in the kidneys, but not in the livers, of hamsters subjected to longterm treatment with either E or 4-OHE (Han and Liehr, 1994) [25] . And by increases in lipid hydro peroxide (Roy and Liehr 1992)) [21] and in lipid-hydro peroxide-induced DNA adducts. Oxidative stress is regarded as an important mechanism for cardiovascular disease development especially atherosclerosis (Singh and Jialal, 2006) [26] . Many disorders of the cardiovascular system include CAD. Autoimmune thrombocytopenia is a bleeding disease and females with AITP have significantly higher oxidative stress levels compared to both female and male AITP controls (Kamhieh and Salama, 2014) [27] .

References

1. Hamid H, Eskicioglu C. Fate of estrogenic hormones in wastewater and sludge treatment: a review of properties and analytical detection techniques in sludge matrix. Water Res. 2012;46:5813-5833.
2. Ryan KJ. Biochemistry of aromatase: significance to female reproductive physiology. Cancer Res. 1982;42(8 Suppl):3342s-3344s. PMID: 7083198.
3. Mechoulam R, Brueggemeier RW, Denlinger DL. Estrogens in insects. Cell Mol Life Sci. 2005;40(9):942944.
4. Lombardi G, Zarrilli S, Colao A, Paesano L, Di Somma C, Rossi F, De Rosa M. Estrogens and health in males. Mol Cell Endocrinol. 2001;178(1-2):51-55. PMID: 11403894.
5. Whitehead SA, Nussey S. Endocrinology: an integrated approach. Oxford: BIOS Scientific Publishers; 2001. ISBN: 978-1-85996-252-7.
6. Soltysik K, Czekaj P. Membrane estrogen receptors-is it an alternative way of estrogen action? J Physiol Pharmacol. 2013;64(2):129-142. PMID: 23756388.
7. Simpson ER, Clyne CD, Rubin GL, Boon WC, Robertson KM, Britt KL, Speed CJ, Jones ME. Aromatase-a brief overview. Annu Rev Physiol. 2002;64:93-127.
8. Mueller SO, Korach KS. Estrogen receptors and endocrine diseases: lessons from estrogen receptor knockout mice. Curr Opin Pharmacol. 2001;1:613-619.
9. Kwan G, Neugarten J, Sherman M, Ding Q, Fotadar U, Lei J, Silbiger S. Effects of sex hormones on mesangial cell proliferation and collagen synthesis. Kidney Int. 1996;50:1173-1179.
10. Harnish DC, Albert LM, Leathurby Y, Eckert AM, Ciarletta A, Kasaian M, Keith JC Jr. Beneficial effects of estrogen treatment in the HLA-B27 transgenic rat model of inflammatory bowel disease. Am J Physiol Gastrointest Liver Physiol. 2004;286:G118-G125.
11. Rajesh KG, Suzuki R, Maeda H, Yamamoto M, Xu Y, Sasaguri S. Hydrophilic bile salt ursodeoxycholic acid protects myocardium against reperfusion injury in a PI3K/Akt dependent pathway. J Mol Cell Cardiol. 2005;39:766-776.
12. Kelly MJ, Levin ER. Rapid actions of plasma membrane estrogen receptors. Trends Endocrinol Metab. 2001;12:152-156.
13. Stevis PE, Deecher DC, Suhadolnik L, Mallis LM, Frail DE. Differential effects of estradiol and estradiol-BSA conjugates. Endocrinology. 1999;140(11):5455-5458.
14. Mobley JA, Brueggemeier RW. Increasing the DNA damage threshold in breast cancer cells. Toxicol Appl Pharmacol. 2002;180:219-226.
15. Olinski R, Siomek A, Rozalski R, Gackowski D, Foksinski M, Guz J, Dziaman T, Szpila A, Tudek B. Oxidative damage to DNA and antioxidant status in aging and age-related diseases. Acta Biochim Pol. 2007;54:11-26.
16. Malins DC, Holmes EH, Polissar NL, Gunselman SJ. The etiology of breast cancer: characteristic alterations in hydroxyl radical-induced DNA base lesions during oncogenesis with potential for evaluating incidence risk. Cancer. 1993;17:3036-3043.
17. Du J, Gebicki JM. DNA degradation and protein peroxidation in cells exposed to hydroxyl free radicals. Redox Rep. 2002;7:329-331.
18. Refsgaard HH, Tsai L, Stadtman ER. Modifications of proteins by polyunsaturated fatty acid peroxidation products. Proc Natl Acad Sci USA. 2000;97:611-616.
19. Liehr JG, Roy D. Free radical generation by redox cycling of estrogens. Free Radic Biol Med. 1990;8:415423.
20. Roy D, Liehr JG. Target organ-specific inactivation of drug metabolizing enzymes in kidney of hamsters treated with estradiol. Mol Cell Biochem. 1992;110:31-39.
21. Nutter LM, Wu YY, Ngo EO, Sierra EE, Gutierrez PL, Abul-Hajj YS. An o-quinone form of estrogen produces free radicals in human breast cancer cells: correlation with DNA damage. Chem Res Toxicol. 1994;7:23-28.
22. Ball P, Knuppen R. Catecholoestrogens: chemistry, biogenesis, metabolism, occurrence and physiological significance. Acta Endocrinol Suppl (Copenh). 1980;232:1-127.
23. Floyd RA. The role of 8-hydroxyguanosine in carcinogenesis. Carcinogenesis. 1990;11:1447-1450.
24. Han X, Liehr JG. DNA single strand breaks in kidneys of Syrian hamsters treated with steroidal estrogens: hormone-induced free radical damage preceding renal malignancy. Carcinogenesis. 1994;15:997-1000.
25. Singh U, Jialal I. Oxidative stress and atherosclerosis. Pathophysiology. 2006;13:129-142.
26. Kamhieh-Milz J, Salama A. Oxidative stress is predominant in female but not in male patients with autoimmune thrombocytopenia. Oxid Med Cell Longev. 2014;2014:720347.