Bariatric Surgery and Cardiovascular Responses to Sodium Nitrate

Changes Induced by Bariatric Surgery in Cardiovascular Responses to Dietary Supplementation With Sodium Nitrate

Inorganic nitrite and nitrate can be reduced to NO and NO-related species such as S-nitrosothiols via the nitrate-nitrite-NO pathway. This is due to the reduction of nitrate to nitrite by the action of bacteria in the mouth and the reduction of nitrite to NO depending on the acidic pH on the stomach or by enzymes with nitrite-reductase activity. The acidic environment of the stomach is very important to the formation of NO and S-nitrosothiols and several studies suggest that changes in gastric pH can affect this conversion. In this context, bariatric surgery, by altering the anatomy of the stomach and increasing gastric pH, can affect the nitrate-nitrite-NO pathway and change the antihypertensive and antioxidant effect of sodium nitrate.

Study Overview

• Status: Completed
• Conditions: Hypertension
• Intervention / Treatment: Dietary supplement: Sodium nitrate

• Study Type: Interventional
• Enrollment (Actual): 30
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Brazil
  • São Paulo
    • Ribeirão Preto, São Paulo, Brazil, 14.048-900
      • Usp - Hospital Das Clínicas Da Faculdade de Medicina de Ribeirão

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• For volunteers who underwent bariatric surgery:

  1. Female;
  2. Age over 18 years old and under 60 years old;
  3. Having had bariatric surgery more than 1 and a half years ago;
  4. Present stabilized weight loss;

• For voluntary controls:

  1. Female;
  2. Age over 18 years old and under 60 years old;

Exclusion Criteria:

• For volunteers who underwent bariatric surgery and controls:

  1. Having uncontrolled blood pressure (above 160/100 mmHg), even with use regulate up to two antihypertensive agents;
  2. Hypertensive patients must be using a maximum of two antihypertensives;
  3. Have Diabetes Mellitus or other endocrinopathy;
  4. Have kidney or liver failure;
  5. Individuals who smoke.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Control group; Sodium nitrate, once a day for 14 days	Dietary supplement: Sodium nitrate; Sodium Nitrate
Experimental: Bariatric group; Sodium nitrate, once a day for 14 days	Dietary supplement: Sodium nitrate; Sodium Nitrate

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Assess changes in s-nitrosothiols	Change in s-nitrosothiols concentration in plasma After Sodium Nitrate Treatment	14 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Assess changes in blood pressure	Change in Blood Pressure After Sodium Nitrate Treatment by Ambulatory blood pressure monitors (ABPMs)	14 days
Assess changes in endotelial function	Change in endotelial function After Sodium Nitrate Treatment by Endopat	14 days
Assess changes in Vascular stiffness	Change in Vascular stiffness After Sodium Nitrate Treatment by pulse wave velocity (PWV)	14 days
Assess changes in nitrate concentration	Change in nitrate concentration in plasma After Sodium Nitrate Treatment	14 days
Assess changes in nitrite concentration	Change in nitrite concentration in plasma After Sodium Nitrate Treatment	14 days

Collaborators and Investigators

• Sponsor: University of Sao Paulo

Study record dates

Study Major Dates

• Study Start (Actual): April 16, 2019
• Primary Completion (Actual): December 17, 2020
• Study Completion (Actual): October 1, 2021

Study Registration Dates

• First Submitted: March 4, 2024
• First Submitted That Met QC Criteria: March 4, 2024
• First Posted (Actual): March 12, 2024

Study Record Updates

• Last Update Posted (Actual): March 12, 2024
• Last Update Submitted That Met QC Criteria: March 4, 2024
• Last Verified: March 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypertension
• Other Study ID Numbers: BACA2019

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No