Oxidative stress Archives - Revista Brasileira de Ginecologia e Obstetrícia
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2024;46:e-rbgo37
To identify the impact of redox imbalance on the clinical evolution of patients with polycystic ovary syndrome and carry out a qualitative and quantitative projection of the benefits of vitamin D supplementation.
Combinations of the keywords polycystic ovary syndrome, vitamin D, oxidative stress, reactive oxygen species, antioxidant, and free radicals were used in PubMed, Cochrane Library, LILACS, EMBASE, and Web of Science databases. The last search was conducted on August 22, 2023.Selection of studies: Based on the inclusion and exclusion criteria, studies were selected considering a low risk of bias, published in the last 5 years in English, which investigated the effects of vitamin D supplementation in women with PCOS, focusing on oxidative stress markers. Of the 136 articles retrieved, 6 intervention studies (445 women) were included.
The risk of bias in included studies was assessed using the Jadad scale, and analysis and visualization of continuous data were performed using Review Manager 5.4.1, summarized as standardized mean differences (SMD) with confidence intervals (CI) of 95%.
Vitamin D effectively reduced malondialdehyde (P=0.002) and total testosterone (P=0.0004) levels and increased total antioxidant capacity levels (P=0.01). Although possible improvements in the modified Ferriman–Gallwey hirsutism score, levels of sex hormone-binding globulin, and free androgen index were identified and the results were not statistically significant.
Vitamin D is a promising alternative for the treatment of PCOS with a positive influence on the oxidative, metabolic, and endocrine disorders of this syndrome.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2024;46:e-rbgo37
To identify the impact of redox imbalance on the clinical evolution of patients with polycystic ovary syndrome and carry out a qualitative and quantitative projection of the benefits of vitamin D supplementation.
Combinations of the keywords polycystic ovary syndrome, vitamin D, oxidative stress, reactive oxygen species, antioxidant, and free radicals were used in PubMed, Cochrane Library, LILACS, EMBASE, and Web of Science databases. The last search was conducted on August 22, 2023.Selection of studies: Based on the inclusion and exclusion criteria, studies were selected considering a low risk of bias, published in the last 5 years in English, which investigated the effects of vitamin D supplementation in women with PCOS, focusing on oxidative stress markers. Of the 136 articles retrieved, 6 intervention studies (445 women) were included.
The risk of bias in included studies was assessed using the Jadad scale, and analysis and visualization of continuous data were performed using Review Manager 5.4.1, summarized as standardized mean differences (SMD) with confidence intervals (CI) of 95%.
Vitamin D effectively reduced malondialdehyde (P=0.002) and total testosterone (P=0.0004) levels and increased total antioxidant capacity levels (P=0.01). Although possible improvements in the modified Ferriman–Gallwey hirsutism score, levels of sex hormone-binding globulin, and free androgen index were identified and the results were not statistically significant.
Vitamin D is a promising alternative for the treatment of PCOS with a positive influence on the oxidative, metabolic, and endocrine disorders of this syndrome.
, , , , , Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2021;43(11):805-810
, , , , , The aim of the present study was to examine the relation between the PON1 polymorphisms and recurrent pregnancy loss (RPL).
In a cross-sectional study, blood samples were collected from 100 females. DNA was extracted and PON1 genotypes were determined by polymerase chain reaction (PCR) amplification.
Regarding PON1 L55M, the mutated allele (M) frequency was found in 70.5% in RPL and in 53.5% in controls; theMallele was significantly associated with an increased risk of RPL (adjusted odds ratio [ORadj]=2.07; 95% confidence interval [CI]; p<0.001). However, regarding PON1 Q192R, the R mutated allele frequency was found in 28.5% in RPL and in 33% in controls. The R allele did not show any risk for RPL (ORadj 0.81; 95%CI; p=0.329).
The present study suggests that there is an effect of genetic polymorphism on RPL and provides additional evidence that combines with the growing information about the ways in which certain PON1 genotypes can affect the development of the fetus in the uterus.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2021;43(11):805-810
, , , , , The aim of the present study was to examine the relation between the PON1 polymorphisms and recurrent pregnancy loss (RPL).
In a cross-sectional study, blood samples were collected from 100 females. DNA was extracted and PON1 genotypes were determined by polymerase chain reaction (PCR) amplification.
Regarding PON1 L55M, the mutated allele (M) frequency was found in 70.5% in RPL and in 53.5% in controls; theMallele was significantly associated with an increased risk of RPL (adjusted odds ratio [ORadj]=2.07; 95% confidence interval [CI]; p<0.001). However, regarding PON1 Q192R, the R mutated allele frequency was found in 28.5% in RPL and in 33% in controls. The R allele did not show any risk for RPL (ORadj 0.81; 95%CI; p=0.329).
The present study suggests that there is an effect of genetic polymorphism on RPL and provides additional evidence that combines with the growing information about the ways in which certain PON1 genotypes can affect the development of the fetus in the uterus.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2015;37(9):411-416
DOI 10.1590/SO100-720320150005397
The aim of this study was to evaluate serum levels of inducible nitric oxide synthase (INOS), myeloperoxidase (MPO), total antioxidant status (TAS), and total oxidative status (TOS) in women with primary ovarian insufficiency (POI) and to compare them with healthy fertile women. We also examined the possible risk factors associated with POI.
This cross-sectional case control study was conducted in Zekai Tahir Burak Women's Health Education and Research Hospital. The study population consisted of 44 women with POI (study group) and 36 healthy fertile women (control group). In all patients, serum levels of INOS, MPO, TAS, and TOS were determined. INOS and MPO levels were measured by enzyme-linked immunosorbent assay whereas colorimetric method was used for evaluating TAS and TOS levels. Age, body mass index (BMI), obstetric history, smoking status, family history, comorbidities, sonographic findings, complete blood count values, C-reactive protein and baseline hormone levels were also analyzed. Student's t-test or Mann-Whitney U test was used to compare continuous variables between the groups; categorical data were evaluated by using Pearson χ2 or Fisher exact test, when appropriate. Binary logistic regression method was used to identify risk factors for POI.
We found significantly elevated levels of INOS (234.1±749.5 versus133.8±143.0; p=0.005), MPO (3,438.7±1,228.6 versus 2,481.9±1,230.1; p=0.001), and TOS (4.3±1.4 versus 3.6±1.4; p=0.02) in the sera of the study group when compared to the BMI-age matched control group. However, difference in serum levels of TAS were not significant between the 2 groups (1.7±0.2 versus 1.6±0.2; p=0.15). Logistic regression method demonstrated that BMI <25 kg/m2, nulliparity, family history of POI, smoking, and elevated serum levels of INOS, MPO, and TOS were independent risk factors for POI.
We found an increase in INOS, MPO, and TOS in women with POI. These serum markers may be promising in early diagnosis of POI. Further large-scale studies are required to determine whether oxidative stress markers have a role in diagnosing POI.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2015;37(9):411-416
DOI 10.1590/SO100-720320150005397
The aim of this study was to evaluate serum levels of inducible nitric oxide synthase (INOS), myeloperoxidase (MPO), total antioxidant status (TAS), and total oxidative status (TOS) in women with primary ovarian insufficiency (POI) and to compare them with healthy fertile women. We also examined the possible risk factors associated with POI.
This cross-sectional case control study was conducted in Zekai Tahir Burak Women's Health Education and Research Hospital. The study population consisted of 44 women with POI (study group) and 36 healthy fertile women (control group). In all patients, serum levels of INOS, MPO, TAS, and TOS were determined. INOS and MPO levels were measured by enzyme-linked immunosorbent assay whereas colorimetric method was used for evaluating TAS and TOS levels. Age, body mass index (BMI), obstetric history, smoking status, family history, comorbidities, sonographic findings, complete blood count values, C-reactive protein and baseline hormone levels were also analyzed. Student's t-test or Mann-Whitney U test was used to compare continuous variables between the groups; categorical data were evaluated by using Pearson χ2 or Fisher exact test, when appropriate. Binary logistic regression method was used to identify risk factors for POI.
We found significantly elevated levels of INOS (234.1±749.5 versus133.8±143.0; p=0.005), MPO (3,438.7±1,228.6 versus 2,481.9±1,230.1; p=0.001), and TOS (4.3±1.4 versus 3.6±1.4; p=0.02) in the sera of the study group when compared to the BMI-age matched control group. However, difference in serum levels of TAS were not significant between the 2 groups (1.7±0.2 versus 1.6±0.2; p=0.15). Logistic regression method demonstrated that BMI <25 kg/m2, nulliparity, family history of POI, smoking, and elevated serum levels of INOS, MPO, and TOS were independent risk factors for POI.
We found an increase in INOS, MPO, and TOS in women with POI. These serum markers may be promising in early diagnosis of POI. Further large-scale studies are required to determine whether oxidative stress markers have a role in diagnosing POI.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2010;32(12):609-616
DOI 10.1590/S0100-72032010001200008
Preeclampsia is a systemic syndrome characterized by inflammatory and antiangiogenic states. The pathogenesis of preeclampsia involves deficient trophoblast invasion that is responsible for altered uterine blood flow and placental oxidative stress. The damaged placenta produces higher concentrations of sFlt-1, a soluble receptor for VEGF and PlGF that is released in the maternal circulation and is involved in endothelial dysfunction. Actually, all processes involved in inflammation, endothelial dysfunction and oxidative stress are strongly correlated and act in a synergistic way. Recent data have shown that an increase in serum concentrations of sFlt-1 initiates 5 to 6 weeks before the clinical manifestations of preeclampsia and these alterations correlate with a decrease in serum concentrations of PlGF. Therefore, both sFlt-1 and PlGF have been suggested to be useful for an early-diagnosis of preeclampsia. The knowledge about the role of antiangiogenic factors in the pathogenesis of preeclampsia has raised the possibility of a therapy involving these factors.In this article we revisited the pathogenesis of preeclampsia addressing its antiangiogenic and inflammatory states.In conclusion, we correlated these alterations with the higher risk for cardiovascular diseases presented by these women in future life.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2010;32(12):609-616
DOI 10.1590/S0100-72032010001200008
Preeclampsia is a systemic syndrome characterized by inflammatory and antiangiogenic states. The pathogenesis of preeclampsia involves deficient trophoblast invasion that is responsible for altered uterine blood flow and placental oxidative stress. The damaged placenta produces higher concentrations of sFlt-1, a soluble receptor for VEGF and PlGF that is released in the maternal circulation and is involved in endothelial dysfunction. Actually, all processes involved in inflammation, endothelial dysfunction and oxidative stress are strongly correlated and act in a synergistic way. Recent data have shown that an increase in serum concentrations of sFlt-1 initiates 5 to 6 weeks before the clinical manifestations of preeclampsia and these alterations correlate with a decrease in serum concentrations of PlGF. Therefore, both sFlt-1 and PlGF have been suggested to be useful for an early-diagnosis of preeclampsia. The knowledge about the role of antiangiogenic factors in the pathogenesis of preeclampsia has raised the possibility of a therapy involving these factors.In this article we revisited the pathogenesis of preeclampsia addressing its antiangiogenic and inflammatory states.In conclusion, we correlated these alterations with the higher risk for cardiovascular diseases presented by these women in future life.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2010;32(6):279-285
DOI 10.1590/S0100-72032010000600005
PURPOSE: to compare serum markers of oxidative stress between infertile patients with and without endometriosis and to assess the association of these markers with disease staging. METHODS: this was a prospective study conducted on 112 consecutive infertile, non-obese patients younger than 39 years, divided into two groups: Endometriosis (n=48, 26 with minimal and mild endometriosis - Stage I/II, and 22 with moderate and severe endometriosis - Stage III/IV) and Control (n=64, with tubal and/or male factor infertility). Blood samples were collected during the early follicular phase of the menstrual cycle for the analysis of serum malondialdehyde, glutathione and total hydroxyperoxide levels by spectrophotometry and of vitamin E by high performance liquid chromatography. The results were compared between the endometriosis and control groups, stage I/II endometriosis and control, stage III/IV endometriosis and control, and between the two endometriosis subgroups. The level of significance was set at 5% (p<0.05) in all analyses. RESULTS: vitamin E and glutathione levels were lower in the serum of infertile women with moderate/severe endometriosis (21.7±6.0 mMol/L and 159.6±77.2 nMol/g protein, respectively) compared to women with minimal and mild endometriosis (28.3±14.4 mMol/L and 199.6±56.1 nMol/g protein, respectively). Total hydroxyperoxide levels were significantly higher in the endometriosis group (8.9±1.8 µMol/g protein) than in the Control Group (8.0±2 µMol/g protein) and among patients with stage III/IV disease (9.7±2.3 µMol/g protein) compared to patients with stage I/II disease (8.2±1.0 µMol/g protein). No significant differences in serum malondialdehyde levels were observed between groups. CONCLUSIONS: we demonstrated a positive association between infertility related to endometriosis, advanced disease stage and increased serum hydroxyperoxide levels, suggesting an increased production of reactive species in women with endometriosis. These data, taken together with the reduction of serum vitamin E and glutathione levels, suggest the occurrence of systemic oxidative stress in women with infertility associated with endometriosis. The reproductive and metabolic implications of oxidative stress should be assessed in future studies.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2010;32(6):279-285
DOI 10.1590/S0100-72032010000600005
PURPOSE: to compare serum markers of oxidative stress between infertile patients with and without endometriosis and to assess the association of these markers with disease staging. METHODS: this was a prospective study conducted on 112 consecutive infertile, non-obese patients younger than 39 years, divided into two groups: Endometriosis (n=48, 26 with minimal and mild endometriosis - Stage I/II, and 22 with moderate and severe endometriosis - Stage III/IV) and Control (n=64, with tubal and/or male factor infertility). Blood samples were collected during the early follicular phase of the menstrual cycle for the analysis of serum malondialdehyde, glutathione and total hydroxyperoxide levels by spectrophotometry and of vitamin E by high performance liquid chromatography. The results were compared between the endometriosis and control groups, stage I/II endometriosis and control, stage III/IV endometriosis and control, and between the two endometriosis subgroups. The level of significance was set at 5% (p<0.05) in all analyses. RESULTS: vitamin E and glutathione levels were lower in the serum of infertile women with moderate/severe endometriosis (21.7±6.0 mMol/L and 159.6±77.2 nMol/g protein, respectively) compared to women with minimal and mild endometriosis (28.3±14.4 mMol/L and 199.6±56.1 nMol/g protein, respectively). Total hydroxyperoxide levels were significantly higher in the endometriosis group (8.9±1.8 µMol/g protein) than in the Control Group (8.0±2 µMol/g protein) and among patients with stage III/IV disease (9.7±2.3 µMol/g protein) compared to patients with stage I/II disease (8.2±1.0 µMol/g protein). No significant differences in serum malondialdehyde levels were observed between groups. CONCLUSIONS: we demonstrated a positive association between infertility related to endometriosis, advanced disease stage and increased serum hydroxyperoxide levels, suggesting an increased production of reactive species in women with endometriosis. These data, taken together with the reduction of serum vitamin E and glutathione levels, suggest the occurrence of systemic oxidative stress in women with infertility associated with endometriosis. The reproductive and metabolic implications of oxidative stress should be assessed in future studies.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2010;32(3):118-125
DOI 10.1590/S0100-72032010000300004
PURPOSE: to compare the serum levels of five markers of oxidative stress and assisted reproduction (AR) outcomes among infertile patients, with tubal and/or male factor and with polycystic ovary syndrome (PCOS). METHODS: 70 patients were included, 58 with tubal and/or male factor infertility and 12 with PCOS, who underwent controlled ovarian stimulation to perform intracytoplasmic sperm injection (ICSI). A blood sample was collected between the third and fifth day of the menstrual cycle in the month prior to ovarian stimulation. We analyzed the levels of malondialdehyde, hydroperoxides, protein oxidation products, glutathione and vitamin E, by reading the absorbance with a spectrophotometer and by high performance liquid chromatography (HPLC). Data were analyzed statistically by the Student's t-test and Fisher's exact test. RESULTS: significant increases in the body mass index, ovarian volume and number of antral follicles were observed in PCOS patients, as well as the use of a lower total dose of follicle stimulating hormone for these patients. There were no differences in the response to ovarian stimulation, in the results of AR or serum levels of malondialdehyde, hydroperoxides, advanced oxidation protein products, glutathione and vitamin E between groups. CONCLUSIONS: the present data did not demonstrate a difference in the levels of serum markers of oxidative stress or in AR results when comparing non-obese infertile patients with PCOS and controls. These data suggest that the results of AR may not be compromised in this specific subgroup of patients with PCOS. However, interpretations of the action of oxidative stress on the results of AR are still not clear and the reproductive implications of oxidative stress need to be better evaluated.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2010;32(3):118-125
DOI 10.1590/S0100-72032010000300004
PURPOSE: to compare the serum levels of five markers of oxidative stress and assisted reproduction (AR) outcomes among infertile patients, with tubal and/or male factor and with polycystic ovary syndrome (PCOS). METHODS: 70 patients were included, 58 with tubal and/or male factor infertility and 12 with PCOS, who underwent controlled ovarian stimulation to perform intracytoplasmic sperm injection (ICSI). A blood sample was collected between the third and fifth day of the menstrual cycle in the month prior to ovarian stimulation. We analyzed the levels of malondialdehyde, hydroperoxides, protein oxidation products, glutathione and vitamin E, by reading the absorbance with a spectrophotometer and by high performance liquid chromatography (HPLC). Data were analyzed statistically by the Student's t-test and Fisher's exact test. RESULTS: significant increases in the body mass index, ovarian volume and number of antral follicles were observed in PCOS patients, as well as the use of a lower total dose of follicle stimulating hormone for these patients. There were no differences in the response to ovarian stimulation, in the results of AR or serum levels of malondialdehyde, hydroperoxides, advanced oxidation protein products, glutathione and vitamin E between groups. CONCLUSIONS: the present data did not demonstrate a difference in the levels of serum markers of oxidative stress or in AR results when comparing non-obese infertile patients with PCOS and controls. These data suggest that the results of AR may not be compromised in this specific subgroup of patients with PCOS. However, interpretations of the action of oxidative stress on the results of AR are still not clear and the reproductive implications of oxidative stress need to be better evaluated.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2007;29(6):303-309
DOI 10.1590/S0100-72032007000600005
PURPOSE: to assess the level of lipid peroxidation (LP) and vitamin E in the follicular fluid and serum of infertile patients, with or without endometriosis, submitted to induction of ovulation for assisted reproduction procedures. METHODS: infertile patients aged 20 to 38 years old were selected prospectively and consecutively and divided into Endometriosis Group (17 patients with pelvic endometriosis) and Control Group (19 patients with previous tubal ligation or with male factor). Blood samples were collected on: D1 (before the beginning of the use of gonadotrophins), D2 (day of human chorionic gonadotrofin application) and D3 (day of oocyte retrieval). On D3, follicular fluid samples free from blood contamination were also collected and stored. LP was assessed for malondialdehyde (MDA) quantification by spectrophotometry, and antioxidant status by measurement of vitamin E by HLPC. RESULTS: on D1, no significant difference in LP was observed between groups. However, vitamin E levels were significantly higher in the Control Group. On D2, LP levels were significantly higher in the Endometriosis Group compared to Control and vitamin E levels continued to be significantly higher in the Control Group. On D3, there was no significant difference in both serum and follicular fluid levels of LP or vitamin E between groups. However, on D3, vitamin E levels were found to be significantly higher in serum than in follicular fluid in both groups, whereas MDA levels were significantly lower in follicular fluid than in serum only in the Control Group. CONCLUSION: before the beginning of the induction of ovulation, a significant decrease in antioxidant status was observed in patients with endometriosis, perhaps because antioxidants are consumed during oxidation reactions. After the induction of ovulation with exogenous gonadotrophins, the group of patients with endometriosis presented not only increased lipid peroxidation compared to Control, but also maintained a lower antioxidant status than the Control Group. However, on the day of oocyte retrieval, both serum LP potential and the levels of vitamin E were found to be similar in both groups.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2007;29(6):303-309
DOI 10.1590/S0100-72032007000600005
PURPOSE: to assess the level of lipid peroxidation (LP) and vitamin E in the follicular fluid and serum of infertile patients, with or without endometriosis, submitted to induction of ovulation for assisted reproduction procedures. METHODS: infertile patients aged 20 to 38 years old were selected prospectively and consecutively and divided into Endometriosis Group (17 patients with pelvic endometriosis) and Control Group (19 patients with previous tubal ligation or with male factor). Blood samples were collected on: D1 (before the beginning of the use of gonadotrophins), D2 (day of human chorionic gonadotrofin application) and D3 (day of oocyte retrieval). On D3, follicular fluid samples free from blood contamination were also collected and stored. LP was assessed for malondialdehyde (MDA) quantification by spectrophotometry, and antioxidant status by measurement of vitamin E by HLPC. RESULTS: on D1, no significant difference in LP was observed between groups. However, vitamin E levels were significantly higher in the Control Group. On D2, LP levels were significantly higher in the Endometriosis Group compared to Control and vitamin E levels continued to be significantly higher in the Control Group. On D3, there was no significant difference in both serum and follicular fluid levels of LP or vitamin E between groups. However, on D3, vitamin E levels were found to be significantly higher in serum than in follicular fluid in both groups, whereas MDA levels were significantly lower in follicular fluid than in serum only in the Control Group. CONCLUSION: before the beginning of the induction of ovulation, a significant decrease in antioxidant status was observed in patients with endometriosis, perhaps because antioxidants are consumed during oxidation reactions. After the induction of ovulation with exogenous gonadotrophins, the group of patients with endometriosis presented not only increased lipid peroxidation compared to Control, but also maintained a lower antioxidant status than the Control Group. However, on the day of oocyte retrieval, both serum LP potential and the levels of vitamin E were found to be similar in both groups.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2007;29(1):27-33
DOI 10.1590/S0100-72032007000100005
PURPOSE: to evaluate oxidative stress in cardiac tissue of ovariectomized rats, with and without hormonal therapy. METHODS: female Wistar rats were divided in three groups: control group (CG); ovariectomized group (OG); ovariectomized group with estrogen supplementation (ESG). The estrogen deprivation was done through bilateral ovariectomy. After one week from the ovariectomy, a pellet of 1.5 mg of 17beta-estradiol was implanted in the ESG animals. Nine weeks after the ovariectomy, cardiac tissue was obtained for the analysis of the oxidative stress through CL (chemiluminescence), and measurement of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and gluthatione peroxidase (GPx). RESULTS: CL was increased in the OG (7348±312 cps/mg protein) when compared with the CG (6250±41 cps/mg protein, p<0.01), but there was no significant difference between the CG and the ESG (6170±237 cps/mg protein). Ovariectomy reduced SOD (35%, p<0.05) and CAT (22%, p<0.001) activities in the OG as compared with the CG. Hormonal therapy normalized antioxidant enzymes activities in the ESG. There was no statistically significant difference in GPx activity among the groups studied. CONCLUSIONS: ovarian hormone deprivation induced an increase of oxidative stress with reduction of antioxidant defenses in the cardiac tissue. However, hormonal therapy prevented oxidative stress after ovariectomy, probably due to an increase of the CAT and SOD activities in the cardiac muscle. These findings suggest an important oxidative stress contribution in cardiovascular dysfunctions observed in women after menopause, reinforcing the importance of hormonal therapy in the management of cardiovascular diseases risk in this group of women.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2007;29(1):27-33
DOI 10.1590/S0100-72032007000100005
PURPOSE: to evaluate oxidative stress in cardiac tissue of ovariectomized rats, with and without hormonal therapy. METHODS: female Wistar rats were divided in three groups: control group (CG); ovariectomized group (OG); ovariectomized group with estrogen supplementation (ESG). The estrogen deprivation was done through bilateral ovariectomy. After one week from the ovariectomy, a pellet of 1.5 mg of 17beta-estradiol was implanted in the ESG animals. Nine weeks after the ovariectomy, cardiac tissue was obtained for the analysis of the oxidative stress through CL (chemiluminescence), and measurement of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and gluthatione peroxidase (GPx). RESULTS: CL was increased in the OG (7348±312 cps/mg protein) when compared with the CG (6250±41 cps/mg protein, p<0.01), but there was no significant difference between the CG and the ESG (6170±237 cps/mg protein). Ovariectomy reduced SOD (35%, p<0.05) and CAT (22%, p<0.001) activities in the OG as compared with the CG. Hormonal therapy normalized antioxidant enzymes activities in the ESG. There was no statistically significant difference in GPx activity among the groups studied. CONCLUSIONS: ovarian hormone deprivation induced an increase of oxidative stress with reduction of antioxidant defenses in the cardiac tissue. However, hormonal therapy prevented oxidative stress after ovariectomy, probably due to an increase of the CAT and SOD activities in the cardiac muscle. These findings suggest an important oxidative stress contribution in cardiovascular dysfunctions observed in women after menopause, reinforcing the importance of hormonal therapy in the management of cardiovascular diseases risk in this group of women.
