A randomized, double-blind, placebo-controlled clinical trial, evaluating the garlic supplement effects on some serum biomarkers of oxidative stress, and quality of life in women with rheumatoid arthritis

Oxidative Stress Mediated Therapy in Patients with Rheumatoid Arthritis: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim of this meta-analysis is to explore all the available literature to obtain updated data about the potential use of antioxidants in the treatment of rheumatoid arthritis (RA) and its ability to reduce disease progression and cardiovascular risk.

METHODS

This systematic review and meta-analysis was performed strictly in accordance with the PRISMA guidelines. English and Chinese databases were searched with a retrieval time up to March 2023. These databases included the PubMed, Embase, Medline Complete, Web of Sciences and Cochrane Collaboration, Wanfang, China National Knowledge Infrastructure, and VIP databases. This literature search was formulated by the two researchers independently. The search strategy consists of reading, collecting the literature, and conducting the preliminary screening. After that, they provide the final selection of the literature according to the inclusion criteria and data extraction. Also, for all studies, the risk bias was assessed to evaluate the quality of the included references. The content of the risk assessment of bias included the following criteria: random allocation method, allocation plan hiding, blind method, completeness of result data, and selectivity of reporting of results, as well as other biases. The main outcomes were clinical efficiency of antioxidant therapy (C-reactive protein, DAS28 score, HAQ, Number of tender joints, etc.) and oxidative stress indicators (catalase, superoxide dismutase, or total antioxidant capacity).

RESULTS

We observed, in most of the studies, the small or moderate effects of antioxidant treatment. The mean effect size is 0.525, and that means that moderate effects were observed in 30 selected RCTs. Also, this effect is confirmed in the 1652 patients with RA with the mean confidence interval of 0.276 (lower limit) and 0.983 (upper limit). Cohen coefficient was calculated at 0.05.

CONCLUSION

The existing evidence is that antioxidants can reduce systemic and local oxidative stress and can reduce damage as the main agent involved in autoimmune diseases such as rheumatoid arthritis.

Beyond Seasoning-The Role of Herbs and Spices in Rheumatic Diseases

Although we have witnessed remarkable progress in understanding the biological mechanisms that lead to the development of rheumatic diseases (RDs), remission is still not achieved in a substantial proportion of patients with the available pharmacological treatment. As a consequence, patients are increasingly looking for complementary adjuvant therapies, including dietary interventions. Herbs and spices have a long historical use, across various cultures worldwide, for both culinary and medicinal purposes. The interest in herbs and spices, beyond their seasoning properties, has dramatically grown in many immune-mediated diseases, including in RDs. Increasing evidence highlights their richness in bioactive molecules, such as sulfur-containing compounds, tannins, alkaloids, phenolic diterpenes, and vitamins, as well as their antioxidant, anti-inflammatory, antitumorigenic, and anticarcinogenic properties. Cinnamon, garlic, ginger, turmeric, and saffron are the most popular spices used in RDs and will be explored throughout this manuscript. With this paper, we intend to provide an updated review of the mechanisms whereby herbs and spices may be of interest in RDs, including through gut microbiota modulation, as well as summarize human studies investigating their effects in Rheumatoid Arthritis, Osteoarthritis, and Fibromyalgia.

Nutrition and its role in prevention and management of rheumatoid arthritis

Accumulating research evidence suggests that nutrition might be implicated in the risk of development and in the management of autoimmune disease, including rheumatoid arthritis (RA), characterized by immune-inflammatory response. Nutrition can have direct roles through the provision of pro- or anti-inflammatory foods, and indirect roles through management of co-morbidity management. The review updates on the evidence relating RA risk and management with focus on specific foods such as fish and diets/dietary patterns such as the Mediterranean diet, fasting and elimination diets and oral nutritional supplements including omega-3 polyunsaturated fatty acids (PUFA). Evidence on herbs and spices, beverages, Vitamin D, and probiotics is also reviewed. Diet has been shown to improve disease activity through reducing inflammation and oxidation and through its beneficial effects on the gut microbiota. Based on the existing evidence, it is recommended that as an adjunct to medical treatment, nutrition therapy for RA should be based on an anti-inflammatory Mediterranean diet (MD) supplemented with at least twice a week consumption of oily fish and/or omega-3 PUFA supplements at 2 g/day. The need for rheumatologists to work more closely with registered dietitians in the management of patients particularly in supporting a well-balanced diet according to individual needs, is highlighted.

Validation of traditional claims of anti-arthritic efficacy of trans-Himalayan snow mountain garlic (Allium ampeloprasum L.) extract using adjuvant-induced arthritis rat model: A comparative evaluation with normal garlic (Allium sativum L.) and dexamethasone

ETHNOPHARMACOLOGICAL RELEVANCE

Snow Mountain Garlic (SMG) (Allium ampeloprasum L.) is a wild trans-Himalayan member of the genus Allium, valued for its anti-inflammatory and anti-arthritic properties in the mountain folk medicinal system (Sowa-Rigpa). Despite its age-old medicinal usage by traditional therapists and the native population for various ailments including rheumatism, there is no scientific validation of its phyto-pharmaceutical merits.

AIM OF THE STUDY

The present pre-clinical study compared the in-vivo anti-arthritic effects of SMG with reported efficacy doses of normal garlic (Allium sativum L.) extract and dexamethasone in a complete Freund's adjuvant (CFA)-induced arthritis rat model.

MATERIALS AND METHODS

The female Wistar rats were immunized by the subplannter injection of CFA into the right hind footpad. Aqueous extracts of SMG and normal garlic were administered orally at a dose of 250 mg/kg and 500 mg/kg for 28 days. Dexamethasone was used as positive control drug. Behavioral parameters including paw markers, arthritis index, joint stiffness, body weight change, etc. were measured. Also, the changes in histopathological indices, hematological profile, inflammatory mediators, and serum cytokines level was determined.

RESULTS

Treatment of rats with SMG extracts significantly (p < 0.001) prevented the reduction in body weight and hematological changes as well as ameliorated clinical symptoms such as arthritic index, joint stiffness, arthritis score, edema, hyperalgesia, and histopathological indices. This was associated with a significant reduction in the serum levels of RF, CRP, anti-CCP, and proinflammatory cytokines exhibiting strong anti-arthritic potential. SMG extracts could also significantly down regulate the NF-κB, COX-2, and iNOS expression in the ankle joint tissues.

CONCLUSIONS

The present study is the first attempt to validate the phyto-pharmaceutical efficacy of this folk garlic variety from the trans-Himalayan region. Overall, SMG extract showed remarkable preventive anti-inflammatory and anti-arthritic activities which were closely comparable to therapeutic effects of dexamethasone and at par or even better than normal garlic w.r.t. several study parameters.

Efficacy and safety of dietary polyphenols in rheumatoid arthritis: A systematic review and meta-analysis of 47 randomized controlled trials

OBJECTIVE

To evaluate safety and efficacy of dietary polyphenols in the treatment of rheumatoid arthritis (RA).

METHODS

CNKI, Pubmed, Cochrane library, Embase were searched to collect randomized controlled trials (RCTs) of dietary polyphenols in the treatment of RA. The databases were searched from the time of their establishment to November 8nd, 2022. After 2 reviewers independently screened the literature, extracted data, and assessed the risk of bias of the included studies, Meta-analysis was performed using RevMan5.4 software.

RESULTS

A total of 49 records (47 RCTs) were finally included, involving 3852 participants and 15 types of dietary polyphenols (Cinnamon extract, Cranberry extract, Crocus sativus L. extract, Curcumin, Garlic extract, Ginger extract, Hesperidin, Olive oil, Pomegranate extract, Puerarin, Quercetin, Resveratrol, Sesamin, Tea polyphenols, Total glucosides of paeony). Pomegranate extract, Resveratrol, Garlic extract, Puerarin, Hesperidin, Ginger extract, Cinnamon extract, Sesamin only involve in 1 RCT. Cranberry extract, Crocus sativus L. extract, Olive oil, Quercetin, Tea polyphenols involve in 2 RCTs. Total glucosides of paeony and Curcumin involve in more than 3 RCTs. These RCTs showed that these dietary polyphenols could improve disease activity score for 28 joints (DAS28), inflammation levels or oxidative stress levels in RA. The addition of dietary polyphenols did not increase adverse events.

CONCLUSION

Dietary polyphenols may improve DAS28, reduce C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), and improve oxidative stress, etc. However, more RCTs are needed to verify or modify the efficacy and safety of dietary polyphenols.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier CRD42022315645.

Aged garlic extract as a potential prophylactic to reduce the progression of endometriosis and associated pain burden

Endometriosis is a complex and potentially debilitating condition that has major impact on quality of life. There is emerging evidence that biological compounds found in garlic (Allium sativum) may be effective for attenuating endometrial pain. Suggested mechanisms for efficacy include modulation of inflammation and potent antioxidant effects. Aged-garlic-extract (AGE) is a centuries old process describing ethanolic extracts of garlic bulbs for 12-20 months. The AGE formulation realised contains a complex array of stabilised biologics with significant immunomodulatory effects relevant to inflammatory conditions. This perspective article puts forward a hypothesis that AGE should be considered as a prophylactic to manage endometrial pain.

Targeting the Gut Microbiome for Inflammation and Pain Management in Orthopedic Conditions

The human gut microbiome can be altered with probiotics, prebiotics, synbiotics, and anti-inflammatory foods and spices as part of an evidence-based strategy that targets inflammation and pain in common orthopedic conditions. Implementing these strategies avoids adverse effects associated with nonsteroidal anti-inflammatory drugs and minimizes the potential for opioid use. This review focuses exclusively on human trials studying the effects of gut microbiome alterations to address pain and inflammatory markers in common orthopedic conditions: osteoarthritis, rheumatoid arthritis, fractures/osteoporosis, and bone pain associated with chemotherapy. Individualized supplementation strategies can be further explored with the information in this review. [Orthopedics. 2022;45(5):e226-e234.].

Indigenous Nigeria medicinal herbal remedies: A potential source for therapeutic against rheumatoid arthritis

Rheumatoid arthritis (RA) is a debilitating disease associated with locomotion impairment, and conventional therapeutic drugs are not optimal for managing RA. There is an avalanche of medications used for the management of RA. Still, studies have shown that they are associated with severe side effects, including hepatotoxicity, retinopathy, and cardiotoxicity disorders of the central nervous system (CNS), skin, blood, and infections. Complementary and alternative medicine (CAM) is currently gaining attention as a novel panacea for managing debilitating diseases, such as RA. Nigerian folk herbal remedies are replete with a plethora of curative medicine, albeit unvalidated scientifically but with seemingly miraculous provenance. Studies of the identification of bioactive compounds present in these botanicals using advanced spectral analytical techniques have enhanced our understanding of the role of Nigerian herbal remedies in the treatment and management of RA. Interestingly, experimental studies abound that the bioactive compounds present in the extracts of plant botanicals protected animals from the development of RA in different experimental models and reduced the toxicity associated with conventional therapeutics. Validated mechanisms of RA amelioration in human and animal models include suppression of the expression of NF-κB, IL-1β, TNF-α, IL-6, IL-8, IL-17, IL-23, chemokines, TGF-β, RANKL, RANK, iNOS, arginase, COX-2, VEGFA, VEGFR, NFATC1, and TRAP in the synoviocytes. Decreased ROS, NO, MDA, carbonyl groups, and PGE₂ in the synovial fluid increased the expression of PPARα/γ; antioxidant and anti-inflammatory molecules also improve RA etiology. In this mini-review, we discuss the global burden of RA, the novel role of plant-based botanicals as potential therapeutics against signaling pathways in RA. Also addressed is the possible repurposing/reprofiling of plant botanicals to increase their therapeutic index among RA patients that patronize traditional healers in Nigeria with a global projection.

The antinociceptive effect of garlic, garlic preparations, and derivative compounds

The antinociceptive effects of garlic have shown promise in treating different chronic diseases in humans, such as knee osteoarthritis, rheumatoid arthritis, and peripheral arterial occlusive disease stage II. The most common garlic products are garlic powder (dried garlic), steam distilled garlic oils, garlic oil macerate, and aged garlic extract. These commercial products contain organosulfur compounds (OSC) that have been extensively evaluated in preclinical models and some clinical assays to treat different diseases against pain. In this review, we describe the importance of some bioactive compounds found in garlic and its role in treating pain. A systematic search of the literature in Dimensions, PubMed, Scopus, Web of Science was performed. Terms and preselected keywords relating to garlic, its derivates and organusulfur compunds in pain, were used to perform a systematic literature search. Two independent reviewers screened papers for inclusion and assessed the methodological quality. The antinociceptive activity of garlic and its OSC is related to its antioxidant and anti-inflammatory properties, which may be explained by the ability to block the synthesis of PGs, pro-inflammatory cytokines and interferon-γ, by the reduction COX- 2 activity and by increases the levels of anti-inflammatory cytokines. Besides, garlic extract is an activator of TRPA1 and TRPV1, where the principal responsible for this activation are OSC. The relationship between these pathways allows a better understanding how garlic and its derivates could be carrying out its pharmacological action over the management of acute and chronic pain and provide a base by further investigations.

The Efficacy of Antioxidative Stress Therapy on Oxidative Stress Levels in Rheumatoid Arthritis: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Objective

To explore the efficacy of antioxidative stress therapy on oxidative stress levels in rheumatoid arthritis (RA) by a systematic review and meta-analysis of randomized controlled trials.

Methods

Chinese and English databases such as PubMed, Embase, China National Knowledge Infrastructure (CNKI), and China Biomedical Literature were searched, mainly searching for clinical randomized controlled trials of antioxidant therapy for rheumatoid arthritis. The search time is from the establishment of the database to July 2021. Two researchers independently carried out literature search, screening, and data extraction. The bias risk tool provided by the Cochrane Collaboration was used to evaluate the bias risk of all the included literature, and the RevMan 5.3 software was used for meta-analysis.

Results

A total of 24 RCTs (28 records) and 1277 participants were included. The time span of randomized controlled trials (RCTs) is from 1986 to 2020. These RCTs involve 14 types of antioxidants or antioxidant therapies, and these therapies have varying degrees of improvement on oxidative stress in RA patients. The summary results showed that the MDA in the experiment group is lower (SMD -0.82, 95% CI -1.35 to -0.28, P = 0.003). The difference of TAC, SOD, NO, GPx, CAT, and GSH between two groups was of no statistical significance (TAC (SMD 0.27, 95% CI -0.21 to 0.75, P = 0.27), SOD (SMD 0.12, 95% CI -0.16 to 0.40, P = 0.41), NO (SMD -2.03, 95% CI -4.22 to 0.16, P = 0.07), GPx (SMD 0.24, 95% CI -0.07 to 0.54, P = 0.13), CAT (SMD 2.95, 95% CI -2.6 to 8.51, P = 0.30), and GSH (SMD 2.46, 95% CI -0.06 to 4.98, P = 0.06)). For adverse events, the summary results showed that the difference was of no statistical significance (RR 1.16, 95% CI 0.79 to 1.71, P = 0.45). In addition, antioxidant therapy has also shown improvement in clinical efficacy indexes (number of tender joints, number of swollen joints, DAS28, VAS, and HAQ) and inflammation indexes (ESR, CRP, TNF-α, and IL6) for RA patients.

Conclusion

The existing evidence shows potential benefits, mainly in reducing MDA and increasing TAC and GSH in some subgroups. However, more large samples and higher quality RCTs are needed to provide high-quality evidence, so as to provide more clinical reference information for the antioxidant treatment of RA.

Effects on health-related quality of life in the randomized, controlled crossover trial ADIRA (Anti-inflammatory Diet In Rheumatoid Arthritis)

Background

Patients with Rheumatoid Arthritis (RA) often report impaired health-related quality of life (HrQoL) such as difficulties in daily life, pain, fatigue and an affected social life. Even when lowering disease activity, pharmacological treatment does not always resolve these factors.

Objective

To investigate if a proposed anti-inflammatory diet improves HrQoL in patients with RA.

Design

In this controlled crossover trial, 50 patients were randomized to start with either an intervention diet (anti-inflammatory) or a control diet (usual Swedish intake) for ten weeks followed by a wash out period before switching to the other diet. Participants received food equivalent to ~1100 kcal/day, five days/week, and instructions to consume similarly for the remaining meals. HrQoL was evaluated using Health Assessment Questionnaire (HAQ), 36-item Short Form Survey (SF-36), Visual Analogue Scales (VAS) for pain, fatigue and morning stiffness, and a time scale for morning stiffness.

Results

Forty-seven participants completed ≥1 diet period and were included in the main analyses. No significant difference between intervention and control diet at end of diet periods was observed for any outcome. However, significant improvements were obtained for SF-36 Physical Functioning (mean:5.79, SE: 2.12, 95% CI: 1.58, 10.01) during the intervention diet period. When excluding participants with anti-rheumatic medication changes, the differences between diet periods increased for most outcomes, favoring the intervention diet period, and the difference for SF-36 Physical Functioning became significant (n = 25, mean:7.90, 95% CI:0.56, 15.24, p = 0.036).

Conclusions

In main analyses, the proposed anti-inflammatory diet did not significantly improve HrQoL for patients with RA compared to control diet. In sub-analyses, significant improvements in physical functioning were detected. Larger studies with consistent medication use and in populations more affected by the disease may be needed to obtain conclusive evidence.

Biomedical Effects of the Phytonutrients Turmeric, Garlic, Cinnamon, Graviola, and Oregano: A Comprehensive Review

Phytonutrients are plant foods that contain many natural bioactive compounds, called phytochemicals, which show specific biological activities. These phytonutrients and their phytochemicals may play an important role in health care maintaining normal organism functions (as preventives) and fighting against diseases (as therapeutics). Phytonutrients’ components are the primary metabolites (i.e., proteins, carbohydrates, and lipids) and phytochemicals or secondary metabolites (i.e., phenolics, alkaloids, organosulfides, and terpenes). For years, several phytonutrients and their phytochemicals have demonstrated specific pharmacological and therapeutic effects in human health such as anticancer, antioxidant, antiviral, anti-inflammatory, antibacterial, antifungal, and immune response. This review summarizes the effects of the most studied or the most popular phytonutrients (i.e., turmeric, garlic, cinnamon, graviola, and oregano) and any reported contraindications. This article also presents the calculated physicochemical properties of the main phytochemicals in the selected phytonutrients using Lipinski’s, Veber’s, and Ghose’s rules. Based on our revisions for this article, all these phytonutrients have consistently shown great potential as preventives and therapeutics on many diseases in vitro, in vivo, and clinical studies.

Effects of Folic Acid Supplementation on Oxidative Stress Markers: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

(1) Background: This systematic review and meta-analysis aimed to assess the effects of folic acid supplementation on oxidative stress markers. (2) Methods: Online database including PubMed, Scopus, Web of Science, and Cochrane were searched up to January 2021, to retrieve randomized controlled trials (RCTs) which examined the effect of folic acid supplementation on markers of oxidative stress. Meta-analyses were carried out using a random-effects model. I² index was used to evaluate the heterogeneity of RCTs. (3) Results: Among the initial 2322 studies that were identified from electronic databases search, 13 studies involving 1013 participants were eligible. Pooled effect size from 13 studies indicated that folic acid supplementation elicits a significant rise in serum concentrations of glutathione (GSH) (WMD: 219.01 umol/L, 95% CI 59.30 to 378.71, p = 0.007) and total antioxidant capacity (TAC) (WMD: 91.70 umol/L, 95% CI 40.52 to 142.88, p < 0.001) but has no effect on serum concentrations of nitric oxide (NO) (WMD: 2.61 umol/L, 95% CI −3.48 to 8.72, p = 0.400). In addition, folic acid supplementation significantly reduced serum concentrations of malondialdehyde (MDA) (WMD: −0.13 umol/L, 95% CI −0.24 to −0.02, p = 0.020). (4) Conclusions: This meta-analysis study suggests that folic acid supplementation may significantly improve markers within the antioxidative defense system by increasing serum concentrations of GSH and TAC and decreasing serum concentrations of MDA.

Potential therapeutic applications of phytoconstituents as immunomodulators: Pre-clinical and clinical evidences

Autoimmune and infectious diseases are the major public health issues and have gained great attention in the last few years for the search of new agents with therapeutic benefits on the host immune functions. In recent years, natural products (NPs) have been studied broadly for their multi-targeted activities under pathological conditions. Interestingly, several attempts have been made to outline the immunomodulatory properties of NPs. Research on in-vitro and in-vivo models have shown the immunomodulatory activity of NPs, is due to their antiinflammatory property, induction of phagocytosis and immune cells stimulation activity. Moreover, studies on humans have suggested that phytomedicines reduce inflammation and could provide appropriate benefits either in single form or complex combinations with other agents preventing disease progression, subsequently enhancing the efficacy of treatment to combat multiple malignancies. However, the exact mechanism of immunomodulation is far from clear, warranting more detailed investigations on their effectiveness. Nevertheless, the reduction of inflammatory cascades is considered as a prime protective mechanism in a number of inflammation regulated autoimmune diseases. Altogether, this review will discuss the biological activities of plant-derived secondary metabolites, such as polyphenols, alkaloids, saponins, polysaccharides and so forth, against various diseases and their potential use as an immunomodulatory agent under pathological conditions.

Effects of garlic supplementation on oxidative stress and antioxidative capacity biomarkers: A systematic review and meta-analysis of randomized controlled trials

Evidence suggests that garlic supplementation may have an effect on oxidative stress by augmenting the rate of enzymatic and non-enzymatic antioxidants and diminishing pro-oxidant enzymes. Given inconsistencies across studies, we aimed to systematically review the current literature and quantify the effects of garlic supplementation on oxidative stress. We conducted a systematic search with multiple databases (Scopus, PubMed, and Web of Science) to find relevant articles published prior to October 2020. Results were reported as bias-corrected standardized mean difference (Hedges' g) with 95% confidence intervals (CI) using random-effects models. Cochrane's Q and I squared (I² ) tests were used to determine heterogeneity among the studies included. Twelve randomized controlled trials (RCTs) were included. Garlic doses ranged from 80 to 4,000 mg/day, and intervention duration varied between 2 and 24 weeks. Garlic supplementation increased serum level of total antioxidant capacity (TAC) (Hedges' g: 2.77, 95% CI: 1.37 to 4.17, p < 0.001) and superoxide dismutase (SOD) (Hedges' g: 13.76, 95% CI: 4.24 to 23.29, p = 0.004), while it reduced the malondialdehyde serum level (MDA) (Hedges' g: -1.94, 95% CI: -3.17 to -0.70, p = 0.002). Due to limited data available, glutathione (GSH) was not considered for the current meta-analysis. The nonlinear dose-response effect of garlic supplementation was not observed with regard to serum TAC and MDA levels (TAC: p-nonlinearity = 0.398; MDA: p-nonlinearity = 0.488). Garlic supplementation appears to improve serum levels of TAC, MDA, and SOD. Garlic supplementation may be useful to reduce oxidative stress and related diseases. Future studies with large sample sizes and longer duration are required to confirm these findings.

Efficacy of Spice Supplementation in Rheumatoid Arthritis: A Systematic Literature Review

BACKGROUND

Spices, i.e., curcumin, ginger, saffron, and cinnamon, have a thousand-year history of medicinal use in Asia. Modern medicine has begun to explore their therapeutic properties during the last few decades. We aimed to perform a systematic literature review (SLR) of randomized controlled trials (RCTs) assessing the effect of spice supplementation on symptoms and disease activity in patients with chronic inflammatory rheumatic diseases (rheumatoid arthritis (RA), spondylarthritis, or psoriatic arthritis).

METHODS

An SLR of RCTs, reviews, and meta-analyses was performed, searching for articles in MEDLINE/PubMed. Abstracts from international rheumatology and nutrition congresses (2017-2020) were also scrutinized. The risk of bias of the selected studies was evaluated using the Cochrane Collaboration's tool and the Jadad scale.

RESULTS

Altogether, six studies, assessing the use of spice supplementation only in RA patients, were included: one on garlic supplementation, two on curcumin, one on ginger, one on cinnamon, and one on saffron supplementation. Garlic, ginger, cinnamon, or saffron supplementation was associated with a decrease in RA clinical activity. However, several points limit the external validity of these studies. No conclusion on the impact of curcumin supplementation on RA activity could be drawn due to low-quality studies.

CONCLUSIONS

Garlic, ginger, cinnamon, and saffron supplementation could have a beneficial effect on RA activity, but the risk of bias of these studies is difficult to assess and data are too limited to recommend them in daily practice.

Effect of Alliaceae Extract Supplementation on Performance and Intestinal Microbiota of Growing-Finishing Pig

Simple Summary

The increasing interest in phytogenics for use with livestock, especially swine and poultry, is mainly due to their antimicrobial, antioxidant, growth-promoting, and gut microbiome modulation properties, which makes them ideal candidates to mitigate the negative effects of the ban on antibiotic growth promoters in the European Union. We tested the ability of Allium spp. extract (containing garlic and onion), one of the best-known phytogenics, used in pig feed, to improve growth performance through modulation of the microbiome and changes in the metabolism of short-chain fatty acids in the gut tract. The promising results obtained in the present study suggested that Allium spp. extracts had the potential to be used in feeding pigs to improve growth performances by modulating the microbiota and metabolism of short-chain fatty acids.

Abstract

The aim of the present study was to ascertain whether an Allium spp. extract rich in organosulfur compounds, such as propyl thiosulfonate (PTSO), added to the feed of growing-finishing pigs at 5 g/kg enhances growth performance or affects the fecal microbiome, the levels of short-chain fatty acids, or the antioxidant capacity of the animals. Fifty male growing pigs (large white) of 23.07 ± 2.87 kg average body weight were randomly allotted to two treatments in a 103-day trial. The trial was divided into two periods, an initial growing phase (56-days) and a finishing phase (47-days). Two dietary treatments for each phase (growing and finishing) were used: a control diet (CON) and an experimental diet consisting of the control diet to which 5 g/kg of Allium spp. extract was added to substitute sepiolite (GAR). Throughout the study, body weight, average daily gain (kg/day, ADG), feed intake (kg/day), and feed conversion ratio (kg/kg) were measured, while the backfat thickness and muscle depth were determined at the end of the study. Besides, feces samples were taken for bacterial counts by means of real-time PCR and short-chain fatty acid (SCFA) profile determination, and the antioxidant capacity was assessed in serum and saliva. In the animals receiving Allium spp. extract (5 g/kg) in the feed, ADG increased (p < 0.05) throughout the trial, Salmonella spp. and Clostridium spp. counts in feces had decreased (p < 0.05) when measured on day 56, and, by day 103, Salmonella spp., Clostridium spp., and Enterobacteriaceae counts had decreased (p < 0.05) and Lactobacillus spp. counts had increased (p < 0.01) in feces. Regarding the SCFA profile in feces and antioxidant capacity measured in serum and saliva, supplementation with Allium spp. extract significantly increased the levels of propionic, isobutyric, and isovaleric acids and the percentage of total branched fatty acids, while the c2/c3 and (c2 + c4)/c3 ratios were lower (p < 0.05) in feces; the Trolox equivalent antioxidant capacity and the cupric reducing antioxidant capacity levels in serum were significantly higher in the same pigs on day 103 than on day 0. Consequently, based on the current results, Allium spp. extract rich in organosulfur compounds, added to the diet at 5 g/kg, had a beneficial effect on the microbiota and would seem to be a possible alternative for increasing the growth performance of growing-finishing pigs. However, further studies on the effects of Allium spp. supplementation on carcass quality are necessary.