Plasma Taurine in Older Women With Obesity: Impact of Metabolic Phenotype and Combined Exercise (non applicable)

Plasma Taurine Concentrations in Older Women With Obesity: The Influence of Metabolic Phenotype and Combined Exercise Training

Population aging has been accompanied by a rise in obesity and other chronic diseases, increasing cardiovascular risk particularly among women, who exhibit a higher prevalence in older age groups compared to men. Aging and obesity share pathophysiological mechanisms, such as chronic inflammation and oxidative stress. However, distinct obesity phenotypes exist, such as metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO). Consequently, therapeutic interventions involving nutritional strategies and physical training are highly relevant, especially for older women. Taurine, a sulfur-containing amino acid, plays a role in modulating oxidative stress, inflammation, osmoregulation, and mitochondrial function. Rationale: Plasma taurine concentrations are lower in women with obesity compared to healthy individuals. However, studies investigating these concentrations across different phenotypes-particularly in older women, a group susceptible to functional and metabolic changes-remain limited. Understanding these variations could clarify taurine's role in the pathophysiology of obesity and aging and inform personalized therapeutic strategies. Combined physical training stands out as an effective strategy for modulating inflammatory, oxidative, and metabolic pathways, in addition to improving psychosocial aspects. Given that taurine levels can be influenced by these pathways, investigating the taurine response to physical training across different metabolic phenotypes may contribute to developing low-cost interventions aimed at improving the quality of life for older women with obesity.

Study Overview

• Status: Not yet recruiting
• Conditions: Metabolically Healthy Obesity; Metabolically Unhealty Obese; Obesity (BMI>30)
• Intervention / Treatment: Behavioral: Physical Training of 16 weeks

Detailed Description

This study aims to investigate differences in plasma taurine concentrations between older women with MHO and MUO, and to evaluate the response of taurine-as well as metabolic, inflammatory, oxidative, and cellular markers-to a 16-week combined physical training intervention. The study will involve 36 older women with obesity, classified as having either MHO or MUO. In Stage 1, nutritional and anthropometric assessments will be conducted, along with the collection of biological samples for biochemical and molecular analyses. In Stage 2, participants will undergo a combined physical exercise intervention for 16 weeks; nutritional, anthropometric, physical performance, and functional assessments will be performed, as well as the collection of biological samples for pre- and post-intervention biochemical and molecular analyses. Stage 3 will consist of integrated data analysis to identify variables predicting plasma taurine concentrations at baseline and post-intervention. Data analysis method: Data will be analyzed using Student's t-tests or Mann-Whitney tests (Stage 1), ANOVA or Kruskal-Wallis tests (Stage 2), Pearson or Spearman correlations (Stages 1 and 2), and linear regression models (Stage 3), using SPSS software (α=5%). Expected results: It is expected that older women with OMS will exhibit higher baseline taurine concentrations and that combined physical training will increase these concentrations in both groups-with a more pronounced effect in the OMS phenotype-in addition to promoting cardiometabolic, functional, inflammatory, oxidative, and psychosocial benefits.

• Study Type: Interventional
• Enrollment (Estimated): 36
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Ellen Cristini de Freitas, Dr; Phone Number: +551633150345; Email: ellenfreitas@usp.br

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• The study will include women with obesity residing in the city or region of Ribeirão Preto, SP, aged 60 to 75 years, who have been physically inactive for at least 3 months. To participate, they must present a body mass index (BMI) ≥ 30 kg/m² (PAHO, 2002) and a body fat percentage ≥ 35%, in accordance with obesity diagnosis criteria (BATSIS et al., 2016; RUBINO et al., 2025). Participants will be classified into two groups (OMS and OMNS) based on the criteria established by Zembic et al. (2021). Classification as OMS applies when all three of the following criteria are met simultaneously: systolic blood pressure (SBP) < 130 mmHg; waist-to-hip ratio < 0.95; and fasting blood glucose < 126 mg/dL. Classification as OMNS applies when two or fewer of these criteria are met.

Exclusion Criteria:

• Participants presenting the following will be excluded from the study: Clinical conditions: contraindication to physical exercise; current or previous diagnosis of neoplasms; autoimmune, hepatic, coronary, renal, neurodegenerative, or infectious diseases; a score of ≤13 on the MMSE (BERTOLUCCI et al., 1994). Previous or ongoing treatments: use of medication for thyroid disorders; participation in training programs, nutritional counseling, or weight loss treatment in the three months prior to the intervention; consumption of supplements such as creatine, omega-3, caffeine, anhydrous beta-alanine, whey protein, and minerals such as zinc, selenium, and/or magnesium. Lifestyle habits: smoking and/or alcohol consumption. Protocol adherence: failure to attend at least 80% of the training sessions (DE CARVALHO et al., 2021). Use of medications: hypoglycemic agents, hypocholesterolemic agents, and/or insulin (BELL; KIVIMAKI; HAMER, 2014).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Metabolically Healthy Obesity (MHO); Women with metabolically healthy obesity who participate in regular exercise. Participants will undergo the study assessments for comparison with the other obesity phenotype.	Behavioral: Physical Training of 16 weeks; Combined physical Training during 16 weeks
Other: Metabolically Unhealthy Obesity (MUO); Women with metabolically unhealthy obesity who participate in regular exercise. Participants will undergo the study assessments for comparison with the other obesity phenotype.	Behavioral: Physical Training of 16 weeks; Combined physical Training during 16 weeks

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Plasma taurine concentrations (µmol/L).	It will be analyzed by high-performance liquid chromatography.	16 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Systolic and diastolic blood pressure (mmHg)	Using sphygmomanometer	16 weeks
Waist and hip circumferences (cm)	non-stretch anthropometric tape	16 weeks
Appendicular lean soft tissue (kg).	Using Dual-energy X-ray Absorptiometry (DXA), often referred to as iDXA, is a low-dose X-ray technology that measures bone mineral density (BMD) and body composition	16 Weeks
Total and regional body fat percentage (%)	Dual-energy X-ray Absorptiometry	16 weeks
Visceral fat (kg)	Dual-energy X-ray Absorptiometry	16 weeks
Body mass (kg)	Dual-energy X-ray Absorptiometry	16 weeks
Body mass index, BMI (kg/m²).	Using body mass and height measurements	16 weeks
Inflammatory and antiinflamatory profile	Changes in serum levels of cytokines will be evaluated with MILLIPLEX® Kit. Pro- inflammatory citokines: IL-1β, MCP-1,TNF-α, IL-6, IL-13 (pg/mL), leptina e PCR-us (mg/dL), IL-10 (pg/mL) e adiponectina (mg/dL).	16 weeks
Food Intake	A food record of three non-consecutive days: two days of the week and one day in the weekend. This evaluation will last 16 weeks. Will be evaluated with Dietwin® software (São Paulo, Brazil): The macronutrients, micronutrients and fiber in quilocalories and percentage (%)	16 weeks
Aerobic performance - VO2	Physical tests performed pre and post- intervention to assess aerobic physical fitness by incremental test in cycle ergometer. The test aim to evaluate VO2peak in ml.kg-1.min-1.	16 weeks
Aerobic performance - LacAnTh	Physical tests performed pre and post- intervention to assess aerobic physical fitness by incremental test in cycle ergometer. The test aim to evaluate: Anaerobic threshold (AT) using lactate concentration [lac-].	16 weeks
Aerobic performance - IAnTh	Physical tests performed pre and post- intervention to assess aerobic physical fitness by incremental test in cycle ergometer. The test aim to evaluate: Anaerobic threshold (AT) using intensity in Watts (W).	16 weeks
Aerobic performance - HRAnTh	Physical tests performed pre and post- intervention to assess aerobic physical fitness by incremental test in cycle ergometer. The test aim to evaluate: Anaerobic threshold (AT) using heart rate (HR).	16 weeks
Food intake - frequency	Application of Food Frequency Questionnaire, QFA-NOVA for each food group (g/group).	16 weeks
Strength test - leg press	Strength test - leg press - maximum repetitions pre and post intervention	16 weeks
Strength test - bench press	Strength test using bench press, pre and post intervention	16 weeks
Funtional capacity: chair sit-to-stand	Funtional capacity evaluation pre and post intervention	16 weeks
handgrip strength	handgrip strength using manual dinamometer	16 weeks
funtional capacity: elbow flexion and extension	funtional capacity: elbow flexion and extension using a dumpbell	16 weeks
Funtional capacity: 6-minute walk test	6-minute walk test using an 30-meter course with markings every 3 meters.	16 weeks
Glycemic profile	Quantified by Total Liquiform Cholesterol Kit, HDL Cholesterol Kit and Liquiform Triglycerides Kit, from Labtest diagnóstica®, using an enzymatic system and absorbance spectrophotometer: Changes in blood glucose (mg/dL).	16 weeks
Lipid profile - Total cholesterol	Quantified by Total Liquiform Cholesterol Kit, HDL Cholesterol Kit and Liquiform Triglycerides Kit, from Labtest diagnóstica®, using an enzymatic system and absorbance spectrophotometer: Changes in total cholesterol (mg/dL).	16 weeks
Lipid profile: HDL-cholesterol and LDL-cholesterol (mg/dL).	Quantified by Total Liquiform Cholesterol Kit, HDL Cholesterol Kit and Liquiform Triglycerides Kit, from Labtest diagnóstica®, using an enzymatic system and absorbance spectrophotometer: Changes in HDL-cholesterol and LDL-cholesterol (mg/dL).	16 weeks
Lipid profile: triglycerides (mg/dL).	Quantified by Total Liquiform Cholesterol Kit, HDL Cholesterol Kit and Liquiform Triglycerides Kit, from Labtest diagnóstica®, using an enzymatic system and absorbance spectrophotometer: Changes in triglycerides (mg/dL).	16 weeks
Glycemic profile - C-peptide	C-peptide pre and post intervention using Chemiluminescence (CLIA - Chemiluminescent Immunoassay)	16 weeks
Expression of inflammatory and anti-inflammatory genes in peripheral blood mononuclear cells (PBMCs)	Using RT-qPCR pre and post-intervention.	16 weeks
Expression of genes related to telomere length: TRF1, TRF2, RAP1, TPP1, POT1, TIN2, and hTERT.	Using RT-qPCR pre and post intervention	16 weeks
Micronutrients (mg/dL)	Blood Zinc, selenium, and magnesium (mg/dL) using spectrophotometry pre and post intervention	16 weeks
Antioxidant enzymes - Superoxide dismutase	Superoxide Dismutase (SOD) Assay Kit Pre and post intervention (U/mg)	16 weeks
Antioxidants enzymes - Catalase (CAT)	Catalase Assay Kit Pre and post intervention (U/mg)	16 weeks
Antioxidants enzymes: Glutationa-peroxidase GPx (U/mg)	Glutathione Peroxidase Assay Kit Pre and post intervention	16 weeks
Oxidative stress markers - Malondialdehyde (nmol/mL).	TBARS (Thiobarbituric Acid Reactive Substances) assay pre and post intervention	16 weeks
Relative telomere length	The assay will be based on quantifying the ratio between the amplification of telomeric sequences (T) and a single-copy gene (S), enabling the estimation of relative telomere length in the biological samples.	16 weeks
Nitrogen balance	Urinary nitrogen excretion (g) will be determined using the Labtest Diagnóstica kit (UREA CE), estimating urinary nitrogen excretion based on urea levels. Daily protein intake will also be used, pre and post intervention	16 weeks

Collaborators and Investigators

• Sponsor: University of Sao Paulo

Study record dates

Study Major Dates

• Study Start (Estimated): October 1, 2026
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): March 1, 2030

Study Registration Dates

• First Submitted: July 13, 2026
• First Submitted That Met QC Criteria: July 13, 2026
• First Posted (Actual): July 17, 2026

Study Record Updates

• Last Update Posted (Actual): July 17, 2026
• Last Update Submitted That Met QC Criteria: July 13, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Aging; Taurine; Physical training; Metabolically unhealthy obesity.; Metabolically healthy obesity.
• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Overweight; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Obesity, Metabolically Benign; Obesity
• Other Study ID Numbers: Taurine_Obesity_Phenotypes; 2025/17801-3 (Other Identifier: São Paulo Research Foundation (FAPESP))

Drug and device information, study documents

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