Name: MARIANA DOS REIS COUTO
Publication date: 26/06/2020
Advisor:
Name |
Role |
|---|---|
| NAZARE SOUZA BISSOLI | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| NAZARE SOUZA BISSOLI | Advisor * |
| ROGER LYRIO DOS SANTOS | Internal Examiner * |
Summary: Studies have shown that estrogen contributes to the proper functioning of the cardiovascular system, since it can modulate the generation of relaxation and contraction factors derived from the endothelium. However, in postmenopausal women, the use of hormone replacement therapy has been presenting risks that potentially outweigh the benefits. Aiming at the need to search for new therapies, this work investigates the non-pharmacological treatment with the probiotic drink Kefir. 8-week-old adult Wistar rats (Rattus norvegicus) were used, isolated the third order mesenteric arteries for the vascular reactivity protocol WHERE concentration-response curves to ACh were performed after pre-contraction with phenylephrine. The evaluation was carried out in the absence and presence of inhibitors - Indomethacin (INDO) - Non-selective cyclooxygenase inhibitor (COX); NS 398 COX-2 selective inhibitor; Apocynin - NADPH oxidase inhibitor; Catalase - enzyme that degrades H2O2 into H2O and O2; Tiron - scavenger of the superoxide anion (oxidative stress). In addition, the mesenteric resistance arteries were dissected and protein expression of angiotensin-converting enzyme (ACE), catalase, superoxide dismutase (SOD), and tissue tumor necrosis factor alpha (TNFα) analyzed. In addition, we also evaluated the fluorescence of superoxide anions. Indomethacin reduced the relaxation response to ACh in the OVX group in the curved concentration response, while in the Kefir group, it does not alter or relax. This can also be observed in the presence of NS 398. Apocinin and Tiron did not alter the relaxation response of ACh in the OVX group or in the OVX-K group. On the other hand, in the presence of catalase, the response to ACh was reduced in the OVX and OVX-K group, however this reduction was greater in the OVX group. The Kefir group shows increased protein expression of ACE and catalase, compared to the OVX group. Regarding the quantification of superoxide production, the OVX-K group has the lowest production when compared to the OVX group, although the NOX-2 protein expression did not show any difference between the groups.
We conclude that Kefir in ovariectomized rats reduced H2O2-induced oxidative stress, increased catalase-antioxidant enzyme, COX2 inflammatory pathway in the response to ACh in resistance vessels of OVX rats when compared to the untreated group. Altogether, we conclude that kefir is a beneficial product a beneficial product in the preventive treatment of vascular dysfunction characteristic of post-menopausal period.
