Abstract
Background
Oxidative stress is a major contributor to postoperative complications in patients undergoing open-heart surgery. Probiotics have been suggested to enhance antioxidant defenses by modulating gut microbiota and reducing systemic inflammation. This study aimed to evaluate the impact of probiotic supplementation on oxidative stress biomarkers in patients undergoing open‑heart surgery.
Methods
A total of 37 patients with cardiovascular disease scheduled for open‑heart surgery were initially recruited, with 18 allocated to the intervention group and 19 to the control group. The intervention, consisting of probiotic supplementation, began 1 day before surgery and continued for 2 weeks, while the control group received a placebo for the same duration. Plasma levels of malondialdehyde (MDA) and total antioxidant capacity (TAC) were measured at baseline and at the end of the intervention using ELISA and colorimetric methods, respectively.
Results
The intervention group had a significant increase in TAC levels from 221.52 ± 24.68 to 356.23 ± 34.57, whereas the control group experienced a decrease from 220.73 ± 14.12 to 209.68 ± 14.83 (F = 15.794; P < 0.001). No significant change was found regarding the effect of probiotic supplementation on the level of MDA.
Conclusion
Probiotic supplementation may improve the postoperative antioxidant status in patients undergoing open-heart surgery. Probiotics may serve as an adjunctive therapy to enhance antioxidant defenses and mitigate postoperative oxidative stress. Further large-scale studies are warranted.
Keywords: antioxidant, heart surgery, malondialdehyde, oxidative stress, postoperative period, probiotics, total antioxidant capacity
Introduction
Open‑heart surgery is a major surgical intervention that induces significant oxidative stress, which may contribute to postoperative complications and delayed recovery [1]. The heightened production of reactive oxygen species (ROS) during surgery, coupled with inflammatory responses and ischemia-reperfusion injury, can overwhelm the body’s antioxidant defense system, leading to cellular damage and impaired physiological function [2]. Clinical studies have reported that lipid peroxidation markers such as malondialdehyde (MDA) can increase more than two‑fold after cardiac surgery, while total antioxidant capacity (TAC) significantly decreases, underscoring the magnitude of oxidative burden in this setting [3,4]. Consequently, identifying effective perioperative strategies to modulate oxidative stress has become a growing area of interest in nutritional and surgical research [5].
Probiotics are live microorganisms that confer health benefits to the host when administered in adequate amounts [6]. In recent years, probiotics have attracted attention for their potential antioxidant and immunomodulatory effects. Experimental and clinical studies suggest that certain probiotic strains can enhance antioxidant capacity [7,8]. Probiotics have gained increasing attention for their potential role in modulating inflammation, oxidative stress, and immune responses [9]. Several studies suggest that probiotics exert antioxidant effects through various mechanisms, including the production of antioxidant enzymes, enhancement of endogenous antioxidant systems, and modulation of gut microbiota-derived metabolites with antioxidative properties [8,10]. Additionally, probiotics have been shown to strengthen intestinal barrier function, reduce systemic endotoxemia, and modulate inflammatory pathways, which may support antioxidant defenses and attenuate postoperative oxidative stress in patients undergoing major surgery [11].
Despite promising mechanistic insights, the effects of probiotics on oxidative stress biomarkers in clinical settings – particularly in major surgeries – remain insufficiently explored. Specifically, two key biomarkers are commonly used to assess oxidative status: TAC and MDA. TAC represents the overall ability of plasma to neutralize free radicals, while MDA is a major product of lipid peroxidation and a widely recognized marker of oxidative damage to cell membranes. These biomarkers are extensively used in clinical studies, particularly in cardiac surgery, to evaluate oxidative stress levels.
Recent trials have demonstrated potential benefits of probiotics in reducing postoperative infections, improving immune function, and shortening hospital stay among surgical patients [12,13]. However, evidence specifically targeting antioxidant indices such as TAC and MDA in patients undergoing open-heart surgery is sparse and inconsistent. Given that cardiopulmonary bypass (CPB) induces significant oxidative damage, patients undergoing this procedure may particularly benefit from probiotic‑driven modulation of antioxidant defenses and attenuation of postoperative oxidative stress.
Considering the limited clinical evidence and the substantial oxidative burden associated with open‑heart surgery, we conducted the present randomized controlled trial to investigate the potential antioxidant effects of probiotics. Specifically, the study aimed to evaluate the impact of perioperative probiotic supplementation on postoperative levels of TAC and MDA in patients undergoing open‑heart surgery. Clarifying this relationship may inform the development of adjunctive nutritional strategies designed to strengthen postoperative antioxidant defenses and potentially reduce oxidative stress-related complications. By assessing key antioxidant biomarkers, this research provides novel insights into the potential role of probiotics in mitigating oxidative stress in patients undergoing open‑heart surgery.
Methods
Study population
This study was conducted as a double‑blind, parallel‑group, randomized controlled trial on patients undergoing open‑heart surgery. In this study, a total of 42 patients were recruited from the hospitals affiliated with Shahid Beheshti University of Medical Sciences, Tehran, Iran. Sample size was calculated using the formula: n = (2 × s2 × (Z1 + Z2)2)/d2, where Z1 = 1.96 (95% confidence), Z2 = 0.84 (80% power), s = estimated SD, and d = minimum detectable difference. Based on this calculation, at least 35 patients were required; considering a 10% dropout rate, 40 patients were recruited. The objectives and methodology of the study were explained to patients with cardiovascular disease who met the inclusion criteria. Written informed consent was obtained from patients who expressed their willingness to participate.
Patients who met the following inclusion criteria were eligible for the study: willingness to participate in the study and provide written informed consent, confirmed diagnosis by a cardiologist indicating the need for open-heart surgery, age over 40 years, no immunodeficiency disorders or gastrointestinal sensitivity to probiotics, BMI greater than or equal to 18, no history of alcohol or recreational drug use, no current use of anti-inflammatory drugs, no use of multivitamin-mineral supplements or medications such as clozapine, theophylline, caffeine, phenothiazine, or tacrine, and no use of medications that interfere with gut microbiome modulation. Initially, 42 patients were included in the study. Patients were excluded if they withdrew consent or were unwilling to continue participation (n = 2), used antioxidant supplements (n = 1), did not comply with the study protocol (n = 1), or experienced gastrointestinal or other adverse effects attributed to the probiotic supplementation (n = 1). Finally, 37 patients (18 patients in the intervention group and 19 patients in the control group) were included in the final analysis.
To address safety monitoring and the potential risks associated with probiotic supplementation in cardiac surgery patients, several precautionary measures were implemented in our study. First, we excluded patients with known immunodeficiency conditions, gastrointestinal sensitivities, and those taking medications or supplements known to alter the gut microbiota or immune function. Second, participants were closely monitored throughout the intervention via regular phone follow-ups and in-person assessments to detect any adverse effects. Moreover, the probiotic formulation used (Comflor) included strains with a long history of safe use in clinical and hospital settings.
General information, including age, gender, duration of disease, types and dosages of medications used for cardiovascular disease management, and history of other illnesses, was obtained through face-to-face interviews with patients. Physical activity levels were assessed using a validated International Physical Activity Questionnaire [14] and were expressed as metabolic equivalent of task (MET). Dietary intake was assessed using a validated 3-day food recall (two weekdays, one weekend day) at baseline and after the 2-week intervention. Patients received instructions from a trained dietitian. Data was analyzed using Nutritionist IV software to estimate energy, macronutrients, and key antioxidant nutrients. Dairy products and fruits were included as covariates in the General Linear Model (GLM) as the main contributors to microbiota and antioxidant intake.
The intervention
Following baseline assessments, participants were randomized into intervention (group A, receiving probiotic supplements) and control (group B, receiving placebo) groups. This study was conducted in a double-blind manner, such that both the participants and the investigators responsible for outcome assessment were unaware of group assignments throughout the trial. Stratified block randomization was employed: patients were first stratified by sex (male and female), and then randomized within blocks of four (e.g. AABB, ABAB, and ABBA) to ensure balance between groups. Allocation was determined using a random number list. The randomization process was conducted by someone independent of the primary investigator to maintain concealment. After randomization, sealed envelopes containing treatment allocation codes were provided to the research team for sample selection and assignment.
Participants in the intervention group received two probiotic capsules daily, taken with or shortly after meals, whereas the control group received placebo capsules. The probiotic supplement (Comflor) and the placebo (starch) were provided by Zist Takhmir Pharmaceutical Company (Tehran, Iran) in identical packaging without distinguishing labels and were similar in taste, smell, color, and appearance. The Comflor supplement contained a probiotic blend of stable lyophilized strains, including Lactobacillus acidophilus, Lactobacillus bulgaricus, Lactobacillus plantarum, Lactobacillus casei, Streptococcus thermophilus, Bifidobacterium longum, Bifidobacterium brovii, and Bifidobacterium infantis at a concentration of 4.5 × 10¹¹ CFU. A multistrain probiotic formulation was selected to provide complementary mechanisms for antioxidant support. Specific strains, such as Lactobacillus plantarum and L. acidophilus, have been shown in in vitro and animal studies to enhance antioxidant enzyme activity [e.g. superoxide dismutase (SOD) and glutathione (GSH)] and TAC [15]. Bifidobacterium longum and B. infantis have demonstrated the ability to reduce systemic oxidative stress and inflammation [16]. Combining these strains may exert a synergistic effect on gut microbiota modulation and antioxidant defense, providing broader protection against oxidative stress associated with cardiac surgery.
Supplementation with probiotics or placebo was initiated one day before surgery and continued for 2 weeks. Baseline measurements were repeated at the end of the intervention. To ensure adherence, patients were monitored via phone calls every 3 days to verify supplement intake, address any questions, be aware of possible complications, and prevent participant dropout. To further assess compliance, participants were asked to return any unused pills at the end of the 2-week period. Throughout the study, all patients were advised to maintain their usual diet, medication dosage, and physical activity levels.
Biochemical measurements
A 10 ml sample of venous blood was collected from participants after 12–14 hours of fasting at both the beginning and end of the 2-week intervention. To separate plasma, the samples were centrifuged at room temperature at 3 000 rpm for 10 min. The isolated plasma was stored in 1 ml microtubes at −80 °C until biochemical analyses were performed.
Plasma TAC concentration was measured using an ELISA method with kits from ZellBio GmbH (Lonsee, Baden‑Württemberg, Germany). Plasma MDA concentration was determined by a colorimetric method using ZellBio GmbH assay kits (Germany).
Data analysis
Data analysis was conducted using SPSS software version 21. A P value of less than 0.05 was considered statistically significant in all analyses. The results of the Kolmogorov–Smirnov test indicated that all quantitative variables were normally distributed (All P > 0.05). The independent samples t-test and chi-squared test were used for quantitative and qualitative variables, respectively. The GLM repeated measures was applied to assess the effects of probiotic supplementation on antioxidant indices after adjustments for age, sex, physical activity, and dietary intake of dairy products and fruits (Fig. 1).
Fig. 1.
CONSORT flowchart of patient enrollment, randomization, and follow‑up in the study. CONSORT, consolidated standards of reporting trials.
Results
General characteristics of the participants at baseline are presented in Table 1. Totally, 37 patients, with a mean age of 62.04 ± 6.56 in the intervention group and 61.70 ± 7.13 in the placebo group, were included (P = 0.871). Baseline analysis revealed that the control group exhibited a significantly greater level of physical activity compared with the intervention group (0.51 ± 0.27 vs. 0.34 ± 0.14 METs; P = 0.014). The groups were not significantly different regarding age, gender, and dietary intake of dairy products and fruits.
Table 1.
The general characteristics of the participants
| Placebo group (N = 19) |
Intervention group (N = 18) |
P valuea | |
|---|---|---|---|
| Age (y) | 61.70 ± 7.13 | 62.04 ± 6.56 | 0.871 |
| Females, n (%) | 10 (52.6%) | 9 (50.0%) | 0.57 |
| Male, n (%) | 9 (47.4%) | 9 (50.0%) | |
| Physical activity (hours/d) | 0.51 ± 0.27 | 0.34 ± 0.14 | 0.014 |
| Dietary intake of dairies | 0.67 ± 0.06 | 0.66 ± 0.06 | 0.947 |
| Dietary intake of fruits | 1.70 ± 0.80 | 1.59 ± 0.67 | 0.633 |
Obtained using independent t-test and qui-squared test for quantitative and qualitative variables, respectively. P < 0.05 was considered as significant.
Table 2 shows the effect of supplementation with probiotics on biochemical parameters of the patients after adjustments for age, sex, physical activity, and dietary intake of dairy products and fruits. TAC demonstrated a significant group × time effect (F = 15.794; P < 0.001). The intervention group exhibited a marked increase in TAC levels from 221.52 ± 24.68 to 356.23 ± 34.57 μmol TE/mL, whereas the placebo group showed a slight decrease from 220.73 ± 14.12 to 209.68 ± 14.83 μmol TE/mL. For MDA, mean values in the intervention group changed from 27.27 ± 4.69 ng/mL at baseline to 14.71 ± 9.45 ng/mL after the intervention, while the placebo group showed a reduction from 17.66 ± 12.60 to 17.35 ± 11.77 ng/mL. These changes, however, did not reach statistical significance (F = 1.638; P = 0.209) (Fig. 2).
Table 2.
The effect of probiotic supplementation on antioxidant indices in the participants after adjustment for the confounders
| Before the intervention | After the intervention | Group*time | ||||
|---|---|---|---|---|---|---|
| Placebo group | Intervention group | Placebo group | Intervention group | F | P valuea | |
| MDA (ng/mL) | 17.66 ± 12.60 | 27.27 ± 4.69 | 17.35 ± 11.77 | 14.71 ± 9.45 | 1.638 | 0.209 |
| TAC (μmol TE/mL) | 220.73 ± 14.12 | 221.52 ± 24.68 | 209.68 ± 14.83 | 356.23 ± 34.57 | 15.794 | <0.001 |
Values are presented as mean ± SD. Statistical analysis was performed using repeated measures ANOVA to assess within‑group changes over time and between‑group differences.
ANOVA, analysis of variance; MDA, malondialdehyde; TAC, total antioxidant capacity.
Adjusted for age, sex, physical activity, and dietary intake of dairy products and fruits.
Fig. 2.
The effect of probiotic supplementation on the levels of total antioxidant capacity (TAC).
Discussion
The present study demonstrated that probiotic supplementation significantly increased antioxidant capacity in patients undergoing open-heart surgery. Specifically, TAC levels increased markedly in the intervention group, while a slight but notable decrease was observed in the placebo group. These findings suggest that probiotics may play a beneficial role in enhancing systemic antioxidant defenses during the postoperative period, potentially mitigating the oxidative stress induced by surgical trauma and CPB.
To understand these results, it is essential to consider the physiological context of oxidative stress in cardiac surgery. Oxidative stress is a well-established consequence of cardiac surgery, primarily driven by ischemia-reperfusion injury, systemic inflammation, and excessive ROS production [1,17]. The depletion of endogenous antioxidant reserves postoperatively can exacerbate cellular damage, contributing to complications such as organ dysfunction and delayed recovery [18]. Therefore, strategies to enhance antioxidant defense mechanisms are of clinical importance. Our findings are in line with previous research suggesting that probiotics may improve antioxidant status in both healthy individuals and those undergoing surgical or critical care interventions [19]. For example, a meta-analysis of randomized controlled trials by Zheng et al. [20] demonstrated that probiotic supplementation significantly increased antioxidant levels and reduced markers of oxidative stress. Another study by Shimizu et al. [21] found that probiotics enhanced antioxidant status and reduced postoperative complications in critically ill patients. These studies reinforce the notion that probiotics may serve as an adjunctive therapeutic approach to reduce oxidative stress in surgical settings.
The significant increase in TAC in the probiotic group could be attributed to several mechanisms. Probiotic supplementation has been demonstrated to enhance antioxidant capacity by modulating gut microbiota composition, strengthening intestinal barrier integrity, and generating bioactive metabolites such as short‑chain fatty acids and polyphenol derivatives. These metabolites exert systemic antioxidative effects primarily through activation of redox‑sensitive signaling pathways, including the nuclear factor erythroid 2–related factor 2 axis [22]. Furthermore, probiotics have been shown to promote the production of antioxidant enzymes such as SOD and glutathione peroxidase, which contribute to neutralizing ROS [7]. However, no statistically significant change was observed in MDA levels, a marker of lipid peroxidation. This discrepancy between TAC and MDA responses underscores the complex and multifactorial nature of oxidative stress regulation. While TAC significantly increased following probiotic supplementation, the absence of changes in MDA, a direct marker of lipid peroxidation, suggests that systemic antioxidant defense may be enhanced without necessarily altering lipid peroxidation pathways. While TAC reflects the overall plasma antioxidant capacity, MDA indicates specific oxidative damage to lipids [23,24]. In addition, this discrepancy may suggest that the observed TAC increase may represent a transient elevation in circulating antioxidants rather than a reduction in cellular oxidative damage [25,26], emphasizing the need for additional biomarkers and longer-term studies to assess clinical relevance.
Several important limitations of this study warrant consideration. First, the intervention duration was relatively short (2 weeks), which may have restricted observable changes in oxidative stress markers. Second, only TAC and MDA were measured; other oxidative stress markers, such as protein carbonyls or 8-isoprostane, were not assessed. Third, dietary antioxidant intake was only partially controlled, and plasma concentrations of key nutrients (e.g. vitamins C and E) were not measured. Fourth, variability in surgical and clinical parameters, including CPB duration and transfusion volume, was not standardized across patients, which may have introduced residual confounding into the observed outcomes. Finally, the contribution of individual probiotic strains and their survival in the gut was not directly verified. Future studies should address these limitations, include a more comprehensive panel of oxidative stress and inflammatory biomarkers, and explore optimal probiotic strains, doses, and intervention duration for maximal clinical benefit.
Conclusion
In summary, probiotic supplementation significantly increased plasma TAC in patients undergoing open-heart surgery, suggesting a potential role in enhancing systemic antioxidant defenses and mitigating postoperative oxidative stress. While the difference of MDA levels did not reach statistical significance, the findings support the concept that probiotics may serve as an adjunctive perioperative strategy to improve redox balance. Future large-scale, multicenter trials with extended follow-up and comprehensive biomarker assessment are warranted to confirm these effects and establish clinical benefits in surgical populations.
Acknowledgements
We are grateful for the good cooperation of the patients participating in the study and the staff of the research department.
Funding for this study was provided by Shahid Beheshti University of Medical Sciences, Tehran, Iran (Code 25896).
The study was designed by F.M. and M.S.H. S.K., S.D., M.S.H., Z.J., M.N., M.T., A.D., and M.F. contributed to the data collection, data analysis, and manuscript review. The final manuscript was reviewed and approved by all authors.
The protocol was approved by the Committee of the Research Ethics Committee at Shahid Beheshti University of Medical Sciences in Tehran, Iran, in accordance with Declaration of Helsinki, and the code of study is (Code: IR.SBMU.RETECH.REC.1400.163).
Written informed consent for publication of anonymized data was obtained from all participants. The authors affirm that no identifying information of individual participants is included in this article.
Institutional consent forms were used in this study.
The datasets used and/or analyzed in this study are available from the corresponding author upon reasonable request.
The study was registered through National Nutrition and Food Technology Research Institute with Trial registration number: IRCT20110510006431N4. Date of registration: 2022-02-16.
Conflicts of interest
There are no conflicts of interest.
References
- 1.Pang Y, Li Y, Zhang Y, Wang H, Lang J, Han L, et al. Effects of inflammation and oxidative stress on postoperative delirium in cardiac surgery. Front Cardiovasc Med 2022; 9:1049600. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Oldman AH, Martin DS, Feelisch M, Grocott MP, Cumpstey AF. Effects of perioperative oxygen concentration on oxidative stress in adult surgical patients: a systematic review. Br J Anaesth 2021; 126:622–632. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Lopez MG, Shotwell MS, Hennessy C, Pretorius M, McIlroy DR, Kimlinger MJ, et al.; ROCS trial investigators. Intraoperative oxygen treatment, oxidative stress, and organ injury following cardiac surgery: a randomized clinical trial. JAMA Surgery 2024; 159:1106–1116. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Cuevas-Budhart MA, Sánchez-Garre M, Sánchez-Bermúdez A, Sobrino-Rodríguez A, Arniella-Blanco MM, Renghea A, et al. Oxidative stress and postoperative outcomes: an umbrella review of systematic reviews and meta-analyses. Antioxidants 2025; 14:1349. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Li J-S, Shuang W-B. Perioperative nutrition optimization: a review of the current literature. Front Nurs 2024; 11:127–137. [Google Scholar]
- 6.Abatenh E, Gizaw B, Tsegay Z, Tefera G, Aynalem E. Health benefits of probiotics. J Bacteriol Infec Dis 2018; 2:17–27. [Google Scholar]
- 7.Hoffmann A, Kleniewska P, Pawliczak R. Antioxidative activity of probiotics. Arch Med Sci 2019; 17:792–804. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Wang Y, Wu Y, Wang Y, Xu H, Mei X, Yu D, et al. Antioxidant properties of probiotic bacteria. Nutrients 2017; 9:521. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Das TK, Pradhan S, Chakrabarti S, Mondal KC, Ghosh K. Current status of probiotic and related health benefits. Appl Food Res 2022; 2:100185. [Google Scholar]
- 10.Blazheva D, Mihaylova D, Averina O, Slavchev A, Brazkova M, Poluektova E, et al. Antioxidant potential of probiotics and postbiotics: a biotechnological approach to improving their stability. 2022; 58:1036–1050. [Google Scholar]
- 11.Zheng Y, Zhang Z, Tang P, Wu Y, Zhang A, Li D, et al. Probiotics fortify intestinal barrier function: a systematic review and meta-analysis of randomized trials. Front Immunol 2023; 14:1143548. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12.Kotzampassi K. Why give my surgical patients probiotics? Nutrients 2022; 14:4389. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 13.Liang R, Li X, Zhou Y, Zhou R, Xu L. Perioperative nutritional status in cardiac surgery patients: a multicenter observational study in Shanghai, China. Gen Thorac Cardiovasc Surg 2025; 27:1–2. doi: 10.1007/s11748-025-02192-5. [DOI] [PubMed] [Google Scholar]
- 14.Moghaddam MB, Aghdam FB, Jafarabadi MA, Allahverdipour H, Nikookheslat SD, Safarpour S. The Iranian Version of International Physical Activity Questionnaire (IPAQ) in Iran: content and construct validity, factor structure, internal consistency and stability. World Appl Sci J 2012; 18:1073–1080. [Google Scholar]
- 15.Feng T, Wang J. Oxidative stress tolerance and antioxidant capacity of lactic acid bacteria as probiotic: a systematic review. Gut microbes 2020; 12:1801944. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.Averina O, Kovtun A, Mavletova D, Ziganshin R, Danilenko V. Reaction of Bifidobacterium longum subsp. Infantis Strain ATCC 15697 to Oxidative Stress. Russ J Genet 2023; 59:779–793. [Google Scholar]
- 17.Stevens JL, Feelisch M, Martin DS. Perioperative oxidative stress: the unseen enemy. Anesth Analg 2019; 129:1749–1760. [DOI] [PubMed] [Google Scholar]
- 18.Sabolová G, Kočan L, Rabajdová M, Rapčanová S, Vašková J. Association of inflammation, oxidative stress, and deteriorated cognitive functions in patients after cardiac surgery. Vessel Plus 2024; 8:1–25. [Google Scholar]
- 19.Averina OV, Poluektova EU, Marsova MV, Danilenko VN. Biomarkers and utility of the antioxidant potential of probiotic Lactobacilli and Bifidobacteria as representatives of the human gut microbiota. Biomedicines 2021; 9:1340. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20.Zheng HJ, Guo J, Jia Q, Huang YS, Huang W-J, Zhang W, et al. The effect of probiotic and synbiotic supplementation on biomarkers of inflammation and oxidative stress in diabetic patients: a systematic review and meta-analysis of randomized controlled trials. Pharmacol Res 2019; 142:303–313. [DOI] [PubMed] [Google Scholar]
- 21.Shimizu K, Ogura H, Asahara T, Nomoto K, Morotomi M, Tasaki O, et al. Probiotic/synbiotic therapy for treating critically ill patients from a gut microbiota perspective. Dig Dis Sci 2013; 58:23–32. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 22.Cuciniello R, Di Meo F, Filosa S, Crispi S, Bergamo P. The antioxidant effect of dietary bioactives arises from the interplay between the physiology of the host and the gut microbiota: involvement of short-chain fatty acids. Antioxidants 2023; 12:1073. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 23.Mohideen K, Chandrasekar K, Ramsridhar S, Rajkumar C, Ghosh S, Dhungel S. Assessment of oxidative stress by the estimation of lipid peroxidation marker malondialdehyde (MDA) in patients with chronic periodontitis: a systematic review and meta-analysis. Int J Dent 2023; 2023:6014706. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 24.Farhangi MA, Vajdi M, Fathollahi P. Dietary total antioxidant capacity (TAC), general and central obesity indices and serum lipids among adults: an updated systematic review and meta-analysis. Int J Vitam Nutr Res 2022; 92:406–422. [DOI] [PubMed] [Google Scholar]
- 25.Yu X, Yan L, Chen L, Shen X, Zhang W. Alleviating effects of probiotic supplementation on biomarkers of inflammation and oxidative stress in non-communicable diseases: a systematic review and meta-analysis using the GRADE approach. BMC Pharmacol Toxicol 2025; 26:124. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26.Silva NS, Cerdeira CD, Dos Reis TM, Rodrigues MR. Effects of probiotics on markers of oxidative/nitrosative stress and damage associated with inflammation in non-communicable diseases: a systematic review and meta-analysis of randomized placebo-controlled trials. Probiotics Antimicrob Proteins 2025; 15:1–22. [DOI] [PubMed] [Google Scholar]