Omega-3 polyunsaturated fatty acids and the treatment of rheumatoid arthritis: a meta-analysis

Effects of nutritional supplements and dietary interventions on rheumatoid arthritis: An umbrella review of meta-analyses of randomized controlled trials

BACKGROUNDS

The effects of nutritional supplements and dietary interventions on rheumatoid arthritis (RA) are still unclear.

OBJECTIVES

This study aimed to evaluate the impact of nutritional supplements and dietary interventions on RA patients.

METHODS

The online databases of PubMed, Web of Science, Embase, and Cochrane Library were used to search the relevant literature from inception to December 2024. Meta-analyses with the inclusion of randomized controlled trials were selected to assess the effects of nutritional supplements or dietary interventions on RA. We accessed the methodological quality of included reviews using AMSTAR 2 and evaluated the quality of evidence for intervention effects using GRADE. Data synthesis and analysis were used by R 4.4.1 and STATA 17.

RESULTS

A total of 14 articles were included, evaluating the effects of nutritional supplements and dietary interventions on RA management. Among these, 3 studies were rated as high quality, 6 as low quality, and 5 as critically low quality by AMSTAR2. The quality of evidence for intervention effects ranges from low to very low quality. The interventions assessed included polyunsaturated fatty acids (PUFAs), probiotics, total glucosides of paeony (TGP), anti-inflammatory diets (AIDs), and others. TGP was the only intervention to significantly reduce both the disease activity score and erythrocyte sedimentation rate, although the quality of evidence for these effects was low. Probiotics contributed to significant reductions in C-reactive protein and visual analogue scale scores, with both outcomes rated as low quality. PUFAs demonstrated significant improvements in tender joint count, swollen joint count, and morning stiffness, though, like the other interventions, these effects were also rated as low quality.

CONCLUSION

There was relatively strong evidence supporting that PUFAs, probiotics, TGP, and AIDs may show some benefits on RA. However, the low quality of evidence highlights the need for further high-quality research and real-world evidence to confirm their effectiveness.

Unlocking the Power of the Mediterranean Diet: Two in One-Dual Benefits for Rheumatic and Thyroid Autoimmune Diseases

In recent years, autoimmune diseases are becoming more and more prevalent worldwide, with this rapid rise being influenced by environmental factors linked to lifestyle changes in modern societies. In this context, the role of diet has been the topic of extensive research as evidence has mounted that particular dietary patterns may contribute to or modulate autoimmunity. The present review specifically focuses on the Mediterranean diet (MD) as a whole dietary pattern, and on its peculiar components, such as n-3 polyunsaturated fatty acids (PUFAs), polyphenols and fiber. We explored their potential benefits in a spectrum of both systemic and organ-specific autoimmune disorders, including rheumatic diseases (like rheumatic arthritis and systemic lupus erythematosus), and thyroid diseases (like Hashimoto's thyroiditis), since they often occur in the same individuals. Here, we offer a comprehensive review about the influence of dietary factors on these autoimmune diseases and potential translation into therapeutic interventions, as an adjuvant therapeutic approach to improve autoimmunity-related outcomes.

Effectiveness of N-3 fatty acids supplementation on spondyloarthritis: A systematic review and meta-analysis

BACKGROUND & AIMS

The study aims to systematically review and meta-analyze randomized controlled trials (RCTs) assessing the effects of n-3 fatty acids (FA) supplementation on spondyloarthritis (SpA) disease activity, inflammatory markers, and imaging.

METHODS

The study protocol was developed and registered online in advance. The PubMed, SCOPUS, and Cochrane Central Register of Controlled Trials (CENTRAL) electronic databases were systematically searched for RCTs up to April 2024. Two independent reviewers screened, assessed for eligibility, and extracted data from the eligible RCTs. The revised Cochrane Risk of Bias tool was used to assess the quality of trials. The random-effects model was used to calculate the pooled estimates.

RESULTS

We included four RCTs, involving 245 patients with SpA. Supplementation with n-3 FA did not improve physician-reported outcomes [number of tender joints (four trials, standardized mean difference (SMD): -0.22; 95 % confidence interval (CI): -0.74 to 0.29; I2 = 61 %), number of swollen joints (two trials, SMD: -0.13; 95 % CI: -0.42 to 0.15; I2 = 0 %)], and patient-reported outcomes [pain (three trials, SMD: -0.16; 95 % CI: -1.03 to 0.70; I2 = 74 %), Health Assessment Questionnaire (three trials, SMD: -0.04; 95 % CI: -0.78 to 0.70; I2 = 71 %). The other nine pre-specified outcomes were not analyzed due to lack of information from the original RCTs which were evaluated as «some concerns» or «high risk» of bias.

CONCLUSIONS

In the present systematic review and meta-analysis including placebo-controlled RCTs, n-3 FA supplementation did not show improvement in the reported outcomes. Future RCTs should be conducted with homogenous intervention, placebo, and outcomes to re-examine possible beneficial effects.

Anti-Inflammatory and Antinociceptive Properties of the Quercetin-3-Oleate AV2, a Novel FFAR1 Partial Agonist

Free fatty acid receptor 1 (FFAR1) has emerged as the most targeted isoform of the free fatty acid receptors because of its involvement in the modulation of energy balance and its potential role in the control of inflammatory and pain conditions. Quercetin-3-oleate (AV2), recognized as a new FFAR1 partial agonist, was investigated for its ability to modulate inflammation and nociception. Human immortal neuroblastoma SH and the murine macrophagic RAW 264.7 cells were used to evaluate cell viability, the potential cytoprotective activity, and the anti-inflammatory properties of AV2 in vitro. Paw edema, caused by zymosan-A, and the formalin test were used to assess the in vivo anti-inflammatory and antinociceptive effects in CD-1 mice. In vitro, AV2 was devoid of cytotoxicity, significantly reduced ROS in both cell types, and protected RAW 264.7 cells from lipopolysaccharide damage by reducing tumor necrosis factor-α production. Interestingly, AV2 induced a transient elevation of intracellular calcium that was reduced in cells, pre-incubated with the FFAR1 antagonist DC260126. In vivo, AV2 reduced formalin-induced nociception and zymosan A-induced paw edema, and both effects were reversed by the FFAR1 antagonist GW1100. In conclusion, these data strongly support the AV2-mediated antioxidant, anti-inflammatory, and antinociceptive activity. AV2 represents a promising molecule for the clinical management of inflammatory-related pain conditions.

Nature of the Association between Rheumatoid Arthritis and Cervical Cancer and Its Potential Therapeutic Implications

It is now established that patients with rheumatoid arthritis (RA) have an increased risk of developing cervical cancer (CC) or its precursor, cervical intraepithelial neoplasia (CIN). However, the underlying mechanisms of this association have not been elucidated. RA is characterized by unresolved chronic inflammation. It is suggested that human papillomavirus (HPV) infection in RA patients exacerbates inflammation, increasing the risk of CC. The tumor microenvironment in RA patients with CC is also marked by chronic inflammation, which aggravates the manifestations of both conditions. Gut and vaginal dysbiosis are also considered potential mechanisms that contribute to the chronic inflammation and aggravation of RA and CC manifestations. Numerous clinical and pre-clinical studies have demonstrated the beneficial effects of various nutritional approaches to attenuate chronic inflammation, including polyunsaturated fatty acids and their derivatives, specialized pro-resolving mediators (SPMs), probiotics, prebiotics, and certain diets. We believe that successful resolution of chronic inflammation and correction of dysbiosis, in combination with current anti-RA and anti-CC therapies, is a promising therapeutic approach for RA and CC. This approach could also reduce the risk of CC development in HPV-infected RA patients.

Effects of omega-3 supplementation on lipid metabolism, inflammation, and disease activity in rheumatoid arthritis: a meta-analysis of randomized controlled trials

INTRODUCTION

Omega-3 possesses anti-inflammatory and lipid metabolism modifying effects in rheumatoid arthritis (RA), but inconsistency exists among previous studies. This meta-analysis intended to explore the effects of omega-3 supplementation on fatty acid distribution, blood lipid profiles, inflammation, and disease activity in RA patients.

METHODS

This meta-analysis followed the Preferred Reporting Item for Systematic Reviews and Meta-Analyses (PRISMA) protocol. PubMed, Web of Science, and Embase databases were searched until August 31, 2023.

RESULTS

Eighteen randomized controlled trials with 1018 RA patients were included. Regarding fatty acid distribution, omega-3 supplementation increased eicosapentaenoic acid (EPA) [standardized mean difference (SMD): 0.74; 95% confidence interval (CI): 0.46, 1.01; P < 0.001] and docosahexanoic acid (DHA) (SMD: 0.62; 95% CI: 0.35, 0.89; P < 0.001), but reduced omega-6:omega-3 ratio (SMD: -1.06; 95% CI: -1.39, -0.73; P < 0.001) in RA patients. Regarding blood lipid, omega-3 supplementation decreased triglyceride (TG) in RA patients (SMD: -0.47; 95% CI: -0.78, -0.16; P = 0.003). Regarding clinical symptoms, omega-3 supplementation reduced tender joint count (TJC) in RA patients (SMD: -0.59; 95% CI: -0.79, -0.39; P < 0.001). Notably, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and disease activity score on 28 joints (DAS28) score were slightly decreased by omega-3 supplementation but without statistical significance (all P > 0.05). Publication bias was low, and stability assessed by sensitivity analysis was good.

CONCLUSION

Omega-3 supplementation increases EPA and DHA, but reduces the omega-6:omega-3 ratio, TG, and TJC in RA patients.

Role of Anti-Inflammatory Diet and Fecal Microbiota Transplant in Psoriatic Arthritis

PURPOSE

Psoriatic arthritis (PsA) is a chronic inflammatory condition with complex and heterogenous manifestations. Although a myriad of treatment options including biologic medications are available to alleviate symptoms and slow disease progression, there is currently no cure for this condition. There has been a recent emergence of understanding about the relationship between the gut microbiome and immune-mediated inflammatory diseases. This has generated interest in the potential role of dietary interventions, particularly anti-inflammatory diets, and fecal microbiota transplant (FMT) as novel therapeutic approaches. The purpose of this narrative review is to examine the role of an anti-inflammatory diet and FMT in turn and whether their combination may offer alternate approaches for the management of PsA.

METHODS

Our non-systematic narrative review was informed by a literature search using PubMed and Google Scholar using the terms anti-inflammatory diet, FMT, nutrition supplements, and PsA. Preclinical studies and non-English language articles were excluded when synthesizing the narrative review.

FINDINGS

Current randomized controlled trials (RCTs) and observational evidence suggest that a hypocaloric diet or Mediterranean diet can help achieve weight loss among PsA patients who are overweight or obese, which in turn reduces inflammation and improves disease activity. However, there is no strong data to support the beneficial effects of intermittent fasting, vitamin supplements, turmeric supplements, probiotics, or omega-3 fatty acid supplements in PsA. Current evidence on the use of FMT in PsA is limited as only one small RCT has been conducted which did not demonstrate efficacy for improving clinical symptoms.

IMPLICATIONS

Clinicians can consider recommending hypocaloric or Mediterranean diets as an adjunct to standard management of PsA, possibly under the guidance of a dietician. Further research is needed to explore the beneficial effects of the synergistic role of combining an anti-inflammatory diet with FMT in PsA.

A systematic review and meta-analysis of the omega-3 fatty acids effects on brain-derived neurotrophic factor (BDNF)

BACKGROUND

Omega-3 fatty acids (omega-3 FAs) have attracted the attention of researchers because of their influence on circulatory levels of brain-derived neurotrophic factor (BDNF). Our objective was to review systematically and Meta-analyze randomized controlled trials (RCTs) to assess the effects of omega-3 FAs supplementation on serum BDNF concentration.

METHODS

Scopus, PubMed, Web of Science, and Cochrane Library were systematically searched until April 2023. The Cochrane risk of bias assessment tool was utilized to evaluate the quality of the studies. A random-effects model was employed to estimate the overall effect size of BDNF levels, using the Standard Mean Difference (SMD) and a 95% confidence interval (CI). The heterogeneity among the studies was assessed using chi-squared and I2 statistics.

RESULTS

A total of 12 studies involving 587 subjects were included. The supplementation of PUFA was found to be associated with a significant increase in serum levels of BNDF in the group receiving the supplements, as compared to the placebo group (SMD: 0.72 pg/mL, 95% CI: 0.28, 1.15; P < 0.001) (I2 = 84.39%, P < 0.001). Sub-group analyses revealed similar findings in trials with fewer than 10 weeks, which utilized both animal (fish oil) and herbal (flaxseed) forms of omega-3 supplements with a high daily dosage of 2000mg.

CONCLUSION

The present systematic review and meta-analysis indicate the efficacy of omega-3 FAs in increasing the serum concentration of BDNF. Therefore, omega-3 FAs should be prioritized as agents for increasing BDNF in interventions.

The effect of vitamin D and omega-3 fatty acid supplementation on pain prevalence and severity in older adults: a large-scale ancillary study of the VITamin D and OmegA-3 triaL (VITAL)

ABSTRACT

A diet supplemented with vitamin D and marine omega-3 fatty acids may prevent and treat painful disorders by promoting the resolution of inflammation. However, large, randomized placebo-controlled trials evaluating the effects of supplementation with omega-3 fatty acids and vitamin D on the presence and severity of pain are lacking. VITamin D and OmegA-3 triaL-Pain (VITAL-Pain) is an ancillary study to the VITAL trial, a large randomized, double-blind, placebo-controlled trial of vitamin D (2000 IU/day) and omega-3 supplementation (1 g/day) over 5.3 years of median follow-up, among 25,871 older men and women. We assessed pain among those reaching the end of the VITAL intervention phase using questions from the 2012 National Health Interview Survey. We used ordinal logistic regression to test the effect of vitamin D and omega-3 fatty acids on the odds ratio (OR) and 95% confidence interval [CI] of reporting higher pain prevalence or severity. Overall, 19,611 participants provided complete pain information at the end of the VITAL trial. The ORs for higher pain prevalence or severity for vitamin D and omega-3 supplementation vs placebo were 0.99 ([CI] 0.94-1.05) and 0.99 ([CI] 0.94-1.04), respectively. There was no interaction between the 2 active treatments. Dietary supplementation with commonly used moderate doses of vitamin D or omega-3 fatty acids over a median of 5.3 years did not result in a lower prevalence or severity of pain in middle-aged and older U.S. adults.

B Cells Dynamic in Aging and the Implications of Nutritional Regulation

Aging negatively affects B cell production, resulting in a decrease in B-1 and B-2 cells and impaired antibody responses. Age-related B cell subsets contribute to inflammation. Investigating age-related alterations in the B-cell pool and developing targeted therapies are crucial for combating autoimmune diseases in the elderly. Additionally, optimal nutrition, including carbohydrates, amino acids, vitamins, and especially lipids, play a vital role in supporting immune function and mitigating the age-related decline in B cell activity. Research on the influence of lipids on B cells shows promise for improving autoimmune diseases. Understanding the aging B-cell pool and considering nutritional interventions can inform strategies for promoting healthy aging and reducing the age-related disease burden.

Standardized mortality ratios in systemic sclerosis: a meta-analysis assessing overall and sex- and disease subtype-specific differences

OBJECTIVE

This study aims to evaluate the overall and sex- and illness subtype-specific standardized mortality ratios (SMRs) in patients with systemic sclerosis (SSc).

METHODS

We searched and examined studies that compared the overall and sex- and illness subtype-specific SMRs in patients with SSc to those in the general population using MEDLINE, EMBASE, and Cochrane databases (until May 2023). We then conducted a meta-analysis of the overall and sex- and illness subtype-specific SMRs in patients with SSc.

RESULTS

Overall, 29 studies including 30,673 patients with SSc and 5582 deaths met the inclusion criteria. Patients with SSc had a higher overall SMR than that in the general population (SMR: 2.742, 95% confidence interval [CI]: 2.224-3.38091, p < 0.001). The SMR significantly increased in populations from Europe, North America, Asia, and Oceania according to regional stratification. A sex-specific meta-analysis revealed a substantial increase in the SMR in both men and women (SMR: 3.598, 95% CI: 3.097-4.180, p < 0.001; SMR: 2.833, 95% CI: 2.4384-3.292, p < 0.001, respectively) and the mortality rate was higher in men compared to women. A substantial increase in the SMR in diffuse cutaneous SSc (dcSSc) and limited cutaneous SSc (lcSSc) was observed in a disease subtype-specific meta-analysis. In addition, the SMR in the dcSSc group was higher than that in the lcSSc group (SMR: 4.726, 95% CI: 3.795-5.885, p < 0.001; SMR: 1.987, 95% CI: 1.586-2.489, p < 0.001, respectively).

CONCLUSION

Our findings demonstrated that the mortality rate in patients with SSc was 2.74-times greater than that in the general population. The mortality rate was higher in men compared to women. Additionally, compared to patients with lcSSc, those with dcSSc showed much higher fatality rates.

The Role of Marine n-3 Polyunsaturated Fatty Acids in Inflammatory-Based Disease: The Case of Rheumatoid Arthritis

Inflammation is a conserved process that involves the activation of immune and non-immune cells aimed at protecting the host from bacteria, viruses, toxins and injury. However, unresolved inflammation and the permanent release of pro-inflammatory mediators are responsible for the promotion of a condition called "low-grade systemic chronic inflammation", which is characterized by tissue and organ damage, metabolic changes and an increased susceptibility to non-communicable diseases. Several studies have demonstrated that different dietary components may influence modifiable risk factors for diverse chronic human pathologies. Marine n-3 polyunsaturated fatty acids (n-3 PUFAs), mainly eicosapentaenoic (EPA) and docosahexaenoic acid (DHA), are well-recognized anti-inflammatory and immunomodulatory agents that are able to influence many aspects of the inflammatory process. The aim of this article is to review the recent literature that relates to the modulation of human disease, such as rheumatoid arthritis, by n-3 PUFAs.

Association between functional FCGR3A F158V and FCGR2A R131H polymorphisms and responsiveness to rituximab in patients with autoimmune diseases: a meta-analysis

OBJECTIVES

To investigate the association between the functional Fc gamma receptor 3 A (FCGR3A) V158F and FCGR2A R131H polymorphisms and rituximab therapy in patients with autoimmune diseases.

METHODS

We searched the Medline, Embase, and Cochrane databases for relevant articles. We conducted a meta-analysis of the association between FCGR3A V158F and FCGR2A R131H polymorphisms and responsiveness to rituximab in patients with autoimmune diseases.

RESULTS

Eleven studies, consisting of 661 responders and 267 non-responders for FCGR3A V158F polymorphism and 156 responders and 89 non-responders for FCGR2A R131H polymorphism, were included. The meta-analysis revealed a significant association between the FCGR3A V allele and responsiveness to rituximab (odds ratio [OR] = 1.600, 95% confidence interval [CI] = 1.268-2.018, P < 0.001). Furthermore, associations were found using the dominant and homozygous contrast models. Subgroup analysis showed an association between the FCGR3A V allele and responsiveness to rituximab in European, RA, ITP, small (<50) and large (≥50) groups, and short- (≤6 months) and long-term follow-up periods (≥6 months). These associations were also found in recessive, dominant or homozygous contrast models. Meta-analysis revealed no association between the FCGR2A R allele and responsiveness to rituximab (OR = 1.243, 95% CI = 0.825-1.873, P = 0.229).

CONCLUSIONS

We demonstrated that the FCGR3A F158V polymorphism is associated with better responsiveness to rituximab therapy in patients with autoimmune diseases, indicating that individuals carrying the FCGR3A V allele will likely respond better to rituximab. However, FCGR2A R131H polymorphism was not associated with better response to rituximab.

Lipid metabolism in regulation of B cell development and autoimmunity

B cells play an important role in adaptive immunity and participate in the process of humoral immunity mainly by secreting antibodies. The entire development and differentiation process of B cells occurs in multiple microenvironments and is regulated by a variety of environmental factors and immune signals. Differentiation biases or disfunction of B cells participate in the process of many autoimmune diseases. Emerging studies report the impact of altered metabolism in B cell biology, including lipid metabolism. Here, we discuss how extracellular lipid environment and metabolites, membrane lipid-related components, and lipid synthesis and catabolism programs coordinate B cell biology and describe the crosstalk of lipid metabolic programs with signal transduction pathways and transcription factors. We conclude with a summary of therapeutic targets for B cell lipid metabolism and signaling in autoimmune diseases and discuss important future directions.

Relative efficacy and safety of Janus kinase inhibitors for the treatment of active psoriatic arthritis: a network meta-analysis

OBJECTIVE

To determine the relative effectiveness and safety of Janus kinase (JAK) inhibitors in active psoriatic arthritis (PsA) patients.

MATERIALS AND METHODS

A Bayesian network meta-analysis was performed using data from randomized controlled trials (RCTs) to evaluate the effectiveness and safety of upadacitinib 30 mg, upadacitinib 15 mg, tofacitinib 10 mg, tofacitinib 5 mg, and filgotinib 200 mg in active PsA patients.

RESULTS

Five RCTs including 2539 patients fulfilled the inclusion criteria. The surface under the cumulative ranking curve (SUCRA) revealed that filgotinib 200 mg had the highest probability of reaching a 20% American College of Rheumatology (ACR20) response rate, followed by upadacitinib 30 mg, upadacitinib 15 mg, tofacitinib 10 mg, tofacitinib 5 mg, and placebo. Upadacitinib 30 mg had the highest probability of achieving the ACR50 and ACR70 response rates, followed by upadacitinib 15 mg, filgotinib 200 mg, tofacitinib 10 mg, tofacitinib 5 mg, and placebo. The SUCRA rating based on the Psoriasis Area and Severity Index response rate of at least 75% (PASI75) showed that tofacitinib 10 mg had the highest probability of achieving this response, followed by upadacitinib 15 mg, filgotinib 200 mg, tofacitinib 5 mg, and placebo. Safety analyses evaluated adverse events (AEs) and serious adverse events (SAEs), but no statistically relevant differences were found.

CONCLUSION

Based on the ACR response rates, filgotinib 200 mg and upadacitinib 30 mg were the most effective, whereas tofacitinib 10 mg was the most effective treatment for PsA based on PASI75. However, treatment options were similar with regard to AEs and SAEs.

Lipid metabolism and rheumatoid arthritis

As a chronic progressive autoimmune disease, rheumatoid arthritis (RA) is characterized by mainly damaging the synovium of peripheral joints and causing joint destruction and early disability. RA is also associated with a high incidence rate and mortality of cardiovascular disease. Recently, the relationship between lipid metabolism and RA has gradually attracted attention. Plasma lipid changes in RA patients are often detected in clinical tests, the systemic inflammatory status and drug treatment of RA patients can interact with the metabolic level of the body. With the development of lipid metabolomics, the changes of lipid small molecules and potential metabolic pathways have been gradually discovered, which makes the lipid metabolism of RA patients or the systemic changes of lipid metabolism after treatment more and more comprehensive. This article reviews the lipid level of RA patients, as well as the relationship between inflammation, joint destruction, cardiovascular disease, and lipid level. In addition, this review describes the effect of anti-rheumatic drugs or dietary intervention on the lipid profile of RA patients to better understand RA.

Association between the functional FCGR3A F158V and FCGR2A R131H polymorphisms and responsiveness to biologics in rheumatoid arthritis patients: A meta-analysis

OBJECTIVES

This study aimed to investigate the association between functional Fc gamma receptor 3A (FCGR3A) V158F and FCGR2A R131H polymorphisms and biologic therapy in rheumatoid arthritis (RA) patients.

METHODS

We searched Medline, Embase, and Cochran databases for available articles. This study is a meta-analysis of the association between the FCGR3A V158F and FCGR2A R131H polymorphisms and their responsiveness to biologics in RA patients.

RESULTS

Seventeen studies involving RA patients with FCGR3A V158F (n = 1884) and FCGR2A R131H (n = 1118) polymorphisms were considered. This meta-analysis showed that the FCGR3A V allele was associated with responsiveness to rituximab (odds ratio [OR] = 1.431, 95% CI = 1.081-1.894, P = 0.012), but not with tumor necrosis factor (TNF) blockers, tocilizumab, or abatacept. A significant association was also found between the FCGR3A V158F polymorphism and responsiveness to biologics using the dominant-recessive model. Additionally, the FCGR3A V158F polymorphism was associated with responsiveness to TNF blockers in the homozygous contrast model. Meta-analysis revealed an association between the FCGR2A RR + RH genotype and responsiveness to biologics (OR = 1.385, 95% CI = 1.007-1.904, P = 0.045).

CONCLUSIONS

This meta-analysis demonstrates that FCGR3A V allele carriers show better responsiveness to rituximab, and FCGR2A R allele carriers may show a better response to biologics in RA treatment. Genotyping of these polymorphisms could be a useful tool to find associations with the responsiveness of personalized medicine to biologics.

Comparative efficacy and safety of infliximab and its biosimilars in patients with rheumatoid arthritis presenting an insufficient response to methotrexate : A network meta-analysis

OBJECTIVE

To assess the relative efficacy and safety of infliximab and its biosimilars in patients with active rheumatoid arthritis (RA) who showed an inadequate response to methotrexate (MTX).

METHODS

We performed a Bayesian network meta-analysis combining direct and indirect evidence from randomized controlled trials (RCTs), comparing the efficacy and safety of infliximab biosimilars versus the originator product in patients with active RA despite receiving MTX.

RESULTS

Overall, 7 RCTs involving 3168 patients, including 7 biologic agents, met the inclusion criteria. The NI-071 was listed at the top left of the diagonal of the league table because it was associated with the most favorable surface under the cumulative ranking curve (SUCRA) for the American College of Rheumatology 20 (ACR20) response rate. SB2 was listed at the bottom right of the diagonal of the league table because it was associated with the least favorable results. Based on SUCRA, NI-071 had the highest probability of being the best treatment agent in terms of the ACR20 response rate (SUCRA = 0.731), followed by ABP 710, CT-P13, BCD-055, infliximab, Exemptia, PF-06438179, and SB2 (SUCRA = 0.311). Although statistically non-significant differences in safety ranking were observed for serious adverse events (SAEs) among the treatment options, ABP 710 presented the highest safety probability (SUCRA = 0.739) while BCD-055 showed the lowest safety profile (SUCRA = 0.289).

CONCLUSION

No significant difference in ACR20 response rates and SAEs were detected between infliximab biosimilars and the originator in the investigated study populations.

Agricultural dust derived bacterial extracellular vesicle mediated inflammation is attenuated by DHA

Dietary long-chain omega-3 polyunsaturated fatty acids (n-3 PUFA) and their pro-resolving metabolites are protective against atherosclerotic disease, and ameliorate systemic inflammatory conditions including lupus erythematosus, psoriasis, and bronchial asthma. Organic bioaerosol inhalation is a common and injurious hazard associated with agricultural occupations such as work in swine concentrated animal feeding operations (CAFOs) and is known to increase the risk for developing respiratory conditions such as asthma and COPD. Nearly all cells secrete membrane-bound vesicles (extracellular vesicles, EVs) that have the capacity to transmit protein, nucleic acid, and lipid signaling mediators between cells. Using a polymer-based isolation technique (ExoQuick, PEG) followed by ultracentrifugation, EVs were isolated from CAFO dust extracts, and were quantified and partially characterized. Here, we investigated the role of the n-3 PUFA docosahexaenoic acid (DHA) as a component of n-6 to n-3 PUFA mixtures used to recapitulate physiologically relevant dietary ratios in the resolution of inflammatory injury caused by exposure to EVs carried by agricultural organic dust in vitro. Primary human bronchial epithelial cells, fibroblasts and monocyte-derived macrophages were exposed to EVs isolated from swine CAFO dust. Cells were treated with mixtures of n-6 and n-3 PUFA during recovery from the EV-induced injury. CAFO dust extract (DE) was found to contain EVs that contributed significantly to the overall consequences of exposure to complete DE. DHA-rich PUFA ratios inhibited DE-derived EV-induced proinflammatory cytokine release dose-dependently. DHA-rich PUFA ratios also reversed the damaging effects of EVs on recellularization of lung matrix scaffolds, accelerated wound healing, and stimulated the release of pro-resolution mediators. These results underscore the importance of n-3 PUFA as anti-inflammatory compounds during recovery from EV-laden environmental dust exposure in the context of cellular responses in vitro, warranting future translational studies.

Unraveling the role of natural functional oils in modulating osteoarthritis related complications

Osteoarthritis (OA) is a common joint disease and has been studied extensively in recent years as no promising therapy available so far for its treatment and remains a great challenge for health care specialists. Although the identification of some major mechanisms that contribute to this disease suggests a plethora of bioactive agents in tackling the associated complications yet OA's pathophysiology is still poorly understood owing to complex mechanistic changes observed. Experimental research is now exploring a wide range of therapeutically effective agents in an effort to find a way to repair OA-related joint degeneration and halt it from getting worse. Data was acquired and reviewed from most relevant and recent studies. This review summarizes the studies that are currently available and focuses on how various unconventional functional oils affect osteoarthritis and the affected joint tissues. An analysis of the recent scientific literature allowed us to highlight the potential anti-arthritic properties of edible oils and their main constituents, which seems to suggest an interesting new potential therapeutic application. Due to eccentric nature of OA, it is necessary to concentrate initially on the management of symptoms. The evidence supporting functional oils chondroprotective potential is still accumulating, underpinning a global need for more sustainable natural sources of treatment. More clinical research that focuses on the consequences of long-term treatment, possible negative effects, and epigenetic implications is necessary to get optimistic results. However, different animal or clinical studies suggest that linolenic and linoleic fatty acids decreased chondrocyte oxidative stress, cartilage breakdown, and expression of inflammatory markers. Distinct fatty acids along with minor components of oils also reduced the generation of prostaglandins and decreased oxidative stress. Furthermore, the potential roles of the main components of edible oils and possible negative results (if any) are also reported. While no severe side effects have been reported for any edible oils. Overall, these studies identify and support the use of functional oils as an adjuvant therapy for the management of OA and as a means of symptomatic alleviation for OA patients. However, to prove the effectiveness or to draw precise conclusions, high-quality clinical trials are required.

The lessebo effect in randomized controlled trials of rituximab in patients with rheumatoid arthritis: a meta-analysis

OBJECTIVE

The goal of this study was to assess the impact of negative expectations associated with receiving a placebo (the lessebo effect) on efficacy outcomes in randomized clinical trials (RCTs) of rituximab in patients with rheumatoid arthritis (RA).

METHODS

We performed a meta-analysis on the American College of Rheumatology 20%, 50%, and 70% (ACR20, 50, 70) response rates in the placebo and active (biosimilar)-controlled groups (reference-pbo and reference-bs) of rituximab showing an insufficient response to methotrexate or tumor necrosis factor. We evaluated the difference in ACR20, 50, 70 response rates between the two groups (reference-bs vs. reference-pbo).

RESULTS

Nine RCTs included a total of 2734 patients with RA. The pooled incidence of ACR20 response rate in the placebo- and active-controlled groups of the rituximab RCTs for RA was 53.1% (95% confidence interval [CI] 49.9-56.3%) and 75.0% (95% CI 71.2-78.4%), respectively. The difference in the ACR20 response rate between the placebo- and active-controlled groups was -20.9% (95% CI -26.9 to 61.9%, p < 0.001). The pooled incidence of ACR50 response rate in the placebo- and active-controlled groups of the rituximab RCTs for RA was 29.0% (95% CI 26.2-32.0%) and 47.4% (95% CI 43.2-51.6%), respectively. The ACR50 response rates were significantly higher in the active-controlled groups than in the placebo-controlled groups (-18.4%; 95% CI -18.4 to -13.4%, p < 0.001). The difference in the ACR70 response rate between the placebo- and active-controlled groups was -14.9% (95% CI -22.2 to -7.6%, p < 0.001). The ACR20, 50, 70 response rates were significantly higher in the active-controlled groups than in the placebo-controlled group.

CONCLUSION

This study shows that the use of a placebo can be associated with a clinically significant reduction in the magnitude of change of the ACR20, 50, 70 response rates in rituximab RCTs for RA. The lessebo effect has potential implications for the development of new treatments and appraisal of current treatment options for RA.

Association between 19 dietary fatty acids intake and rheumatoid arthritis: Results of a nationwide survey

BACKGROUND

The relationship between dietary fatty acid intakes and rheumatoid arthritis (RA) is unclear and the available studies have focused on only a few fatty acids. This study investigated the association between the intake of 19 dietary fatty acids and RA in U.S. adults.

METHODS

This cross-sectional study using nationally representative data from the 2010-2020 National Health and Nutrition Examination Survey (NHANES). Multivariate linear regression model, multivariate logic regression models, smoothing curve fitting, and two-segment linear regression model were used to explore the relationships between 19 dietary fatty acids intakes with high-sensitivity C-reactive protein (Hs-CRP) and RA risk.

RESULTS

A total of 16,530 participants were included (1053 participants with RA). Intake of hexadecanoic acid and octadecanoic acid were significantly associated with higher Hs-CRP levels, intake of hexadecenoic acid was significantly associated with higher RA risk, and intake of docosahexaenoic acid was significantly associated with lower RA risk. In addition, there was an inverted U-shaped relationship between total monounsaturated fatty acids (MUFAs) intake and RA risk, with the inflection point reached at 15.77% .

CONCLUSIONS

Among the 19 dietary fatty acids, only 4 subclasses were significantly associated with Hs-CRP or RA risk. The inverted U-shaped relationship between MUFAs and RA risk may provide insights to find potential prevention strategies for RA.

Impact of health and lifestyle food supplements on periodontal tissues and health

According to the new classification, periodontitis is defined as a chronic multifactorial inflammatory disease associated with dysbiotic biofilms and characterized by progressive destruction of the tooth-supporting apparatus. This definition, based on the current scientific evidence, clearly indicates and emphasizes, beside the microbial component dental biofilm, the importance of the inflammatory reaction in the progressive destruction of periodontal tissues. The idea to modulate this inflammatory reaction in order to decrease or even cease the progressive destruction was, therefore, a logical consequence. Attempts to achieve this goal involve various kinds of anti-inflammatory drugs or medications. However, there is also an increasing effort in using food supplements or so-called natural food ingredients to modulate patients' immune responses and maybe even improve the healing of periodontal tissues. The aim of this chapter of Periodontology 2000 is to review the evidence of various food supplements and ingredients regarding their possible effects on periodontal inflammation and wound healing. This review may help researchers and clinicians to evaluate the current evidence and to stimulate further research in this area.

Associations between the interleukin-6 rs1800795 G/C and interleukin-6 receptor rs12083537 A/G polymorphisms and response to disease-modifying antirheumatic drugs in rheumatoid arthritis: A meta-analysis

OBJECTIVE

We aimed to investigate the association between interleukin-6 (IL-6) rs1800795 G/C, IL-6 receptor (IL-6R) rs12083537 A/G, and rs4329505 T/C polymorphisms and responsiveness to disease-modifying antirheumatic drugs (DMARDs) in patients with rheumatoid arthritis (RA).

METHODS

We searched Medline, Embase, and Web of Science databases. We conducted a meta-analysis of studies on the association between the IL-6 rs1800795 G/C, IL-6R rs12083537 A/G and rs4329505 T/C polymorphisms and responsiveness to DMARDs in RA patients.

RESULTS

Fourteen studies from eight published articles involving 982 patients were included in this meta-analysis. The meta-analysis showed a significant association between the IL-6 rs1800795 G allele and response to DMARDs in RA (P = 0.008). Stratification by DMARD class showed that the IL-6 rs1800795 G allele was significantly associated with responsiveness to biological DMARDs (bDMARDs) (P = 0.022), but not conventional synthetic DMARDs (P = 0.145). A significant association was also found between the IL-6 rs1800795 G/C polymorphism and response to DMARDs. The meta-analysis revealed a significant association between the IL-6R rs12083537 A allele and response to tocilizumab in RA patients (P = 0.001). A significant association was also found between the IL-6R rs12083537 AA genotype and response to tocilizumab in RA patients (P = 0.001). However, no association was found between the IL-6R rs4329505 T/C polymorphism and response to tocilizumab.

CONCLUSIONS

This meta-analysis revealed associations between treatment response to bDMARDs and the IL-6 rs1800795 G/C polymorphism, and between response to tocilizumab and the IL-6R rs12083537 A/G polymorphism in RA.

Efficacy of the omega-3 fatty acids supplementation on inflammatory biomarkers: An umbrella meta-analysis

BACKGROUND

Existing meta-analyses on omega-3 polyunsaturated fatty acids and their anti-inflammatory effects have reported uncertain findings. The current umbrella meta-analysis aimed to assess the findings of multiple meta-analyses on the efficacy of n-3 PUFAs on inflammatory biomarkers in adults with different health conditions.

METHODS

Using suitable keywords, articles published until December 2021 were searched in PubMed/Medline, Web of Science, Scopus, EMBASE, and Google Scholar. Meta-analyses investigating the impact of supplementation of n-3 PUFAs on inflammatory biomarkers in adults were included. We performed this meta-analysis using a random-effects model.

RESULTS

Overall, 32 meta-analyses were qualified in this umbrella meta-analysis. Our findings demonstrated that the n-3 PUFA supplementation significantly reduced serum C-reactive protein (CRP) (ES = -0.40; 95 % CI: -0.56, -0.24, p < 0.001; I² = 89.5 %, p < 0.001), Tumour necrosis factor α (TNFα) (ES = -0.23; 95 % CI: -0.37, -0.08, p = 0.002; I² = 60.1 %, p < 0.001), and interleukin 6 (IL-6) concentrations (ES = -0.22; 95 % CI: -0.39, -0.05, p = 0.010; I² = 66.2 %, p < 0.001).

CONCLUSION

The current umbrella meta-analysis found that supplementation of n-3 PUFAs in adults can improve CRP, TNF-α, and IL-6 concentrations under various health conditions. n-3 PUFAs can be recommended as adjuvant anti-inflammatory agents.

Efficacy of n-3 fatty acid supplementation on rheumatoid arthritis' disease activity indicators: a systematic review and meta-analysis of randomized placebo-controlled trials

Theoretical evidence and previous studies suggest that oralnutrient supplementation (ONS) with n-3 fatty acids for rheumatoid arthritis (RA) has the potential to lower disease activity indicators and non-steroidal anti-inflammatory drug (NSAID) uptake. A systematic search was conducted on five databases/registries from inception until May 23, 2021 with the aim to identify randomized placebo-controlled trials comparing n-3 supplements to placebo on disease-specific outcomes. A total of 23 studies matched the criteria (PROSPERO: CRD42019137041). Pooled analyses revealed that n-3 ONS provided a small effect in reducing pain [standardized mean difference (SMD): -0.16, 95% confidence intervals (CI): -0.40 to 0.09], and tender (SMD: -0.20, 95% CI: -0.46 to 0.05) and swollen joint count (SMD: -0.10, 95% CI: -0.28 to 0.07). In sensitivity analyses, there was a small effect in the reduction of NSAIDs intake (SMD: -0.22, 95% CI: -0.90 to 0.46), and c-reactive protein was reduced only by 0.21 mg/dL (95% CI: -0.75 to 0.33). Similar findings were observed regarding other objective/subjective outcomes. The certainty of the evidence was mostly of "very low/low" quality. Overall, n-3 ONS in RA might have a limited clinical benefit. Previous findings suggesting a reduction in NSAID intake may have been biased from the inadequate blinding of interventions.

Influence of supplement administration of omega-3 on the subcutaneous tissue response of endodontic sealers in Wistar rats

AIM

Natural substances such as omega-3 have been used in the medical field due to their numerous properties and, in particular, modulating effect on the systemic and local inflammatory processes. Thus, this study evaluated the influence of omega-3 supplementation on the subcutaneous tissue response of endodontic sealers in Wistar Rats.

METHODOLOGY

Polyethylene tubes were implanted in the subcutaneous tissue of 48 animals (one empty for control and three filled with Sealapex, AH Plus or Endofill). The animals were treated with omega-3 (TO) or water (TW). Treatments started 15 days before implantation until euthanasia. After 5, 15 and 30 days (n = 8), animals were euthanized and polyethylene tubes and surrounding tissue were removed and processed for histological analysis. The inflammatory reaction was analysed by Haematoxylin and Eosin stain and immunolabelling for IL-6 and TNF-α. The collagen maturity was analysed by picrosirius red stain and calcium deposition by von Kossa stain and polarized light. Results were statistically analysed (p < .05).

RESULTS

Amongst TW sealer groups, Endofill evoked a more intense inflammatory infiltrate compared with AH Plus and control in the 30-day period (p = .009). However, in TO sealer groups, there was no difference amongst the sealers and control in all periods (p > .05). Comparing each sealer as a function of the supplementation with water or omega-3, there are differences for Endofill (p = .001) and Sealapex (p = .005) in the 30-day period, presenting lower inflammatory infiltrate in the animals treated with omega-3. A higher percentage of immature fibres was observed at 15 and 30 days in the TO group, compared with the TW group (p < .05). The deposition of calcium particles was observed only by Sealapex in all periods, despite the supplementation procedure.

CONCLUSIONS

Omega-3 supplementation influence the tissue reactions of endodontic sealers, modulating inflammation, the immunolabelling of IL-6 and TNF-α, the repair process and it does not interfere with calcium deposition.

Impact of type and dose of oral polyunsaturated fatty acid supplementation on disease activity in inflammatory rheumatic diseases: a systematic literature review and meta-analysis

Background

Polyunsaturated fatty acid (PUFA) supplementation has been reported to improve disease activity in inflammatory rheumatic diseases (IRDs). However, data are often conflicting and studies insufficiently large to draw conclusions. This systematic literature review and meta-analysis aimed to better estimate the effect of oral supplementation with omega (n)-3 and n-6 PUFA on IRD activity in terms of duration, dose, type, and source.

Methods

The literature was searched in PubMed, EMBASE, and Cochrane Library databases up to October 2020. Studies were reviewed in accordance with PRISMA guidelines. The effect of PUFA supplementation on disease activity was expressed as the standardized mean difference (95% CI). Metaregression and subgroup analyses involved type of IRD, Jadad score, PUFA source (animal or vegetable), and doses.

Results

We obtained 42 references; 30 randomized controlled studies were included comparing the effects of PUFA versus control on disease activity (710 IRD patients receiving PUFA supplementation and 710 controls, most with rheumatoid arthritis). We found a significant improvement in pain, swollen and tender joint count, Disease Activity Score in 28 joints, and Health Assessment Questionnaire score in IRD patients receiving PUFA supplementation as compared with controls, with a significant decrease in erythrocyte sedimentation rate but not C-reactive protein level. Although meta-regression revealed no difference by IRD type or source or dose of PUFA supplementation, subgroup analysis revealed more parameters significantly improved with animal- than vegetable-derived PUFAs and 3- to 6-month supplementation. Most studies examined high-dose supplementation (>2 g/day).

Conclusion

PUFA consumption, especially omega-3 from animal source >2 g/day, may improve IRD activity and might be an adjuvant therapy in rheumatoid arthritis.

Trial registration

The protocol was registered at PROSPERO (CRD42021253685).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02781-2.

Omega-3 Fatty Acids and Balanced Gut Microbiota on Chronic Inflammatory Diseases: A Close Look at Ulcerative Colitis and Rheumatoid Arthritis Pathogenesis

The aim of this article was to review experimental and clinical studies regarding the use of omega-3 fatty acids on the prevention and control of chronic inflammatory diseases with autoimmune background through the gut microbiota modulation. For this, natural omega-3 sources are presented emphasizing the importance of a healthy diet for the body's homeostasis and the enzymatic processes that these fatty acids go through once inside the body. The pathogenesis of ulcerative colitis and rheumatoid arthritis are revisited under the light of the gut microbiota dysbiosis approach and how those fatty acids are able to prevent and control these two pathological conditions that are responsible for the global chronic burden and functional disability and life-threatening comorbidities if not treated properly. As a matter of reflection, as we are living a pandemic crisis owing to COVID-19 infection, we present the potential of omega-3 in preventing a poor prognosis once they contribute to balancing the immune system modulation the inflammatory process.

Immunoregulatory Effect of Preventive Supplementation of Omega-3 Fatty Acid in a Complex Regional Pain Syndrome Type I Model in Mice

Objective

Complex regional pain syndrome (CRPS) is usually triggered by trauma or a surgical procedure, and it typically becomes an established one after an intense inflammatory process with chronic pain and edema as the main symptoms. Available treatments for CRPS have low efficacy. This study aimed to evaluate the clinical and immunoregulatory effects of omega-3 polyunsaturated fatty acid (PUFA) supplementation on paw edema and anti- and pro-inflammatory cytokines and macrophage phenotypes in the chronic post-ischemia pain (CPIP) preclinical model of CRPS-Type I.

Methods

Female Swiss mice were supplemented with omega-3, corn oil, or saline and then submitted to the CPIP model of ischemia/reperfusion (I/R) injury. Supplementation was carried out for 30 days prior to and up to 2 or 15 days after the induction of CPIP, according to experimental protocols. The supplementation protocol included 1,500 mg/kg of omega-3 or corn oil through an intragastric route (gavage). Paw edema, interleukin- (IL-) 4, IL-10, transforming growth factor-β1 (TGF-β1), monocyte chemotactic protein-1 (MCP-1), and tumor necrosis factor (TNF) were then measured in the paw skin and muscle by enzyme-linked immunosorbent assay (ELISA), and macrophage phenotypes (M1 and M2) assessed in the paw muscle by Western blotting.

Results

The CPIP model induced an increase in paw thickness up to 72 h post-I/R. Mice supplemented with omega-3 compared to the saline group displayed reduced edema but neither altered skin IL-4 or skin and muscle TGF-β1, TNF, and MCP-1 concentrations, nor did they exhibit significantly altered muscle macrophage phenotype on the 2nd-day post-CPIP. However, omega-3 supplementation reversed the I/R-related reduction in IL-4 in the paw muscle compared to groups supplemented with saline and corn oil. Furthermore, omega-3 promoted the reduction of IL-10 levels in the paw skin, compared to animals with lesions supplemented with saline, until the 2nd-day post-CPIP. On the 15th day post-CPIP, IL-10 was significantly increased in the muscle of animals supplemented with omega-3 compared to the saline group.

Conclusion

The results suggest that omega-3 PUFA supplementation has anti-inflammatory effects in the CPIP model of CRPS-Type I, significantly reducing paw edema and regulating concentrations of anti-inflammatory cytokines, including IL-4 and IL-10.

The effect of flaxseed with or without anti-inflammatory diet in patients with rheumatoid arthritis, a randomized controlled trial

PURPOSE

Beneficial effect of long-chain ω-3 fatty acids against symptoms of rheumatoid arthritis (RA) has been indicated in previous studies. We examined the effect of flaxseed and anti-inflammatory diet in patients with RA.

METHODS

The 12-week intervention was performed on 120 patients with RA who were randomized to three groups of flaxseed (30 g/day) plus anti-inflammatory diet (AIF group), flaxseed (30 g/day) plus regular diet (RF group), and roasted wheat (30 g/day) plus regular diet (RW group). Disease Activity Score 28-joints (DAS28), health assessment questionnaire (HAQ) disability and pain, quality of life, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor, and anti-cyclic citrullinated peptides (anti-CCP) were measured before and after trial. Analysis was performed using per-protocol and intention-to-treat (ITT) approaches.

RESULTS

One hundred and two patients completed the protocol. Flaxseed decreased DAS28 in RF group compared to RW (- 0.87 ± 1.11 vs. - 0.24 ± 0.78; P = 0.014). Pain severity (P ≤ 0.001), morning stiffness (P < 0.05), and disease feeling (P < 0.01) decreased significantly in AIF and RF groups. HAQ disability and quality of life measurements improved in all 3 groups, with a greater extent in AIF and RF groups (P < 0.001) compared to RW. Between-group differences were significant for DAS28, pain scores, and physical and mental health variables. ESR, CRP, anti-CCP, and rheumatoid factor were not different between groups. Results of ITT analysis did not cause much difference.

CONCLUSIONS

In conclusion, flaxseed may be used as a helpful adjuvant therapy for patients with RA. Calls are open for examining the effect of anti-inflammatory diet on RA symptoms.

TRIAL REGISTRATION NUMBER

Registered at irct.ir as IRCT20190923044858N1, February 6, 2020.

Effect of Anti-Inflammatory Diets on Pain in Rheumatoid Arthritis: A Systematic Review and Meta-Analysis

Various nutritional therapies have been proposed in rheumatoid arthritis, particularly diets rich in ω-3 fatty acids, which may lead to eicosanoid reduction. Our aim was to investigate the effect of potentially anti-inflammatory diets (Mediterranean, vegetarian, vegan, ketogenic) on pain. The primary outcome was pain on a 10 cm visual analogue scale. Secondary outcomes were C-reactive protein levels, erythrocyte sedimentation rate, health assessment questionnaire, disease activity score 28, tender/swollen joint counts, weight, and body mass index. We searched MEDLINE (OVID), Embase (Elsevier), and CINAHL for studies published from database inception to 12 November 2021. Two authors independently assessed studies for inclusion, extracted study data, and assessed the risk of bias. We performed a meta-analysis with all eligible randomized controlled trials using RevMan 5. We used mean differences or standardized mean differences and the inverse variance method of pooling using a random-effects model. The search retrieved 564 unique publications, of which we included 12 in the systematic review and 7 in the meta-analysis. All studies had a high risk of bias and the evidence was very low. The main conclusion is that anti-inflammatory diets resulted in significantly lower pain than ordinary diets (-9.22 mm; 95% CI -14.15 to -4.29; p = 0.0002; 7 RCTs, 326 participants).

Gut microbiota mediated the protective effects of tuna oil on collagen-induced arthritis in mice

Rheumatoid arthritis is emerging as a chronic autoimmune disease worldwide. In this study, the beneficial effects of tuna oil (TO) on collagen-induced arthritis (CIA) mice were investigated. Dietary administration of TO relieved arthritis severity and joint bone erosion, and ameliorated systemic inflammation. Furthermore, TO treatments regulated the phosphorylation of nuclear factor-kappa B (NF-κB) and Wnt1/β-catenin signaling pathways in the joint, enhanced osteoblastogenesis biomarkers and suppressed osteoclastogenesis biomarkers, and subsequently re-balanced bone remodeling. Moreover, the impaired intestinal epithelial barrier was repaired after TO treatments, along with gut microbiota modulation. By employing fecal microbiota transplantation, we clarified that the beneficial effects of TO in CIA alleviation were mediated by the modulated gut microbiota. These results indicated that gut microbiota mediated the protective effects of tuna oil on collagen-induced arthritis in mice.

Diet can exert both analgesic and pronociceptive effects in acute and chronic pain models: a systematic review of preclinical studies

BACKGROUND

Although diet is an essential aspect of human health, the link between diet and pain is still not well understood. Preclinical animal research provides information to understand underlying mechanisms that allow identifying the needs for human research.

OBJECTIVES

This study aims to give a systematic overview of the current evidence from preclinical studies regarding the analgesic and pronociceptive effects of various diets in non-neuropathic, non-cancer, or non-visceral acute and chronic pain models.

STUDY DESIGN

A systematic Review.

SETTING

This study examined studies that investigate the analgesic and pronociceptive effects of various diets in non-neuropathic, non-cancer, or non-visceral acute and chronic pain models.

METHODS

This review was conducted following the PRISMA guidelines and was registered in PROSPERO with the registration number CRD42019133473. The certainty of evidence was examined by a modified GRADE approach.

RESULTS

After the screening process twenty-four eligible papers were included in this review. Nineteen studies examined acute pain, nine studies chronic inflammatory pain, and four studies assessed both acute and chronic pain models.

LIMITATIONS

Due to the heterogeneity of the included studies, a meta-analysis was not included in this study.

CONCLUSIONS

In animal models, excessive saturated, monounsaturated or omega-6 polyunsaturated fat ingestion and diets rich in fats and carbohydrates can decrease pain sensitivity in acute nociceptive pain, whereas it can induce mechanical allodynia and heat hyperalgesia in chronic inflammatory pain. Additionally, diets rich in anti-inflammatory ingredients, as well as a calorie-restricted diet can promote recovery from primary mechanical allodynia and heat hyperalgesia in chronic inflammatory pain.

Perspective: The Saturated Fat-Unsaturated Oil Dilemma: Relations of Dietary Fatty Acids and Serum Cholesterol, Atherosclerosis, Inflammation, Cancer, and All-Cause Mortality

PUFAs are known to regulate cholesterol synthesis and cellular uptake by multiple mechanisms that do not involve SFAs. Polymorphisms in any of the numerous proteins involved in cholesterol homeostasis, as a result of genetic variation, could lead to higher or lower serum cholesterol. PUFAs are susceptible to lipid peroxidation, which can lead to oxidative stress, inflammation, atherosclerosis, cancer, and disorders associated with inflammation, such as insulin resistance, arthritis, and numerous inflammatory syndromes. Eicosanoids from arachidonic acid are among the most powerful mediators that initiate an immune response, and a wide range of PUFA metabolites regulate numerous physiological processes. There is a misconception that dietary SFAs can cause inflammation, although endogenous palmitic acid is converted to ceramides and other cell constituents involved in an inflammatory response after it is initiated by lipid mediators derived from PUFAs. This article will discuss the many misconceptions regarding how dietary lipids regulate serum cholesterol, the fact that all-cause death rate is higher in humans with low compared with normal or moderately elevated serum total cholesterol, the numerous adverse effects of increasing dietary PUFAs or carbohydrate relative to SFAs, as well as metabolic conversion of PUFAs to SFAs and MUFAs as a protective mechanism. Consequently, dietary saturated fats seem to be less harmful than the proposed alternatives.

Rheumatoid arthritis and dietary interventions: systematic review of clinical trials

CONTEXT

The impact of various dietary interventions on rheumatoid arthritis (RA), characterized by immune-inflammatory response, has been subject to increased attention.

OBJECTIVE

A systematic review was conducted to update the current knowledge on the effects of nutritional, dietary supplement, and fasting interventions on RA outcomes.

DATA SOURCES

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, with prespecification of all methods, Medline and Embase were systematically searched for relevant articles.

DATA EXTRACTION

Data were extracted by 2 independent reviewers.

RESULTS

A total of 70 human studies were identified. Administration of omega-3 polyunsaturated fatty acids at high doses resulted in a reduction in RA disease activity and a lower failure rate of pharmacotherapy. Vitamin D supplementation and dietary sodium restriction were beneficial on some RA outcomes. Fasting resulted in significant but transient subjective improvements. While the Mediterranean diet demonstrated improvements in some RA disease activity measures, outcomes from vegetarian, elimination, peptide, or elemental diets suggested that responses are very individualized.

CONCLUSION

Some dietary approaches may improve RA symptoms and thus it is recommended that nutrition should be routinely addressed.

Fatty Acids and Oxylipins in Osteoarthritis and Rheumatoid Arthritis-a Complex Field with Significant Potential for Future Treatments

Purpose of Review

Osteoarthritis (OA) and rheumatoid arthritis (RA) are characterized by abnormal lipid metabolism manifested as altered fatty acid (FA) profiles of synovial fluid and tissues and in the way dietary FA supplements can influence the symptoms of especially RA. In addition to classic eicosanoids, the potential roles of polyunsaturated FA (PUFA)-derived specialized pro-resolving lipid mediators (SPM) have become the focus of intensive research. Here, we summarize the current state of knowledge of the roles of FA and oxylipins in the degradation or protection of synovial joints.

Recent Findings

There exists discordance between the large body of literature from cell culture and animal experiments on the adverse and beneficial effects of individual FA and the lack of effective treatments for joint destruction in OA and RA patients. Saturated 16:0 and 18:0 induce mostly deleterious effects, while long-chain n-3 PUFA, especially 20:5n-3, have positive influence on joint health. The situation can be more complex for n-6 PUFA, such as 18:2n-6, 20:4n-6, and its derivative prostaglandin E₂, with a combination of potentially adverse and beneficial effects. SPM analogs have future potential as analgesics for arthritic pain.

Summary

Alterations in FA profiles and their potential implications in SPM production may affect joint lubrication, synovial inflammation, pannus formation, as well as cartilage and bone degradation and contribute to the pathogeneses of inflammatory joint diseases. Further research directions include high-quality randomized controlled trials on dietary FA supplements and investigations on the significance of lipid composition of microvesicle membrane and cargo in joint diseases.

Nutraceuticals: Transformation of Conventional Foods into Health Promoters/Disease Preventers and Safety Considerations

Nutraceuticals are essential food constituents that provide nutritional benefits as well as medicinal effects. The benefits of these foods are due to the presence of active compounds such as carotenoids, collagen hydrolysate, and dietary fibers. Nutraceuticals have been found to positively affect cardiovascular and immune system health and have a role in infection and cancer prevention. Nutraceuticals can be categorized into different classes based on their nature and mode of action. In this review, different classifications of nutraceuticals and their potential therapeutic activity, such as anti-cancer, antioxidant, anti-inflammatory and anti-lipid activity in disease will be reviewed. Moreover, the different mechanisms of action of these products, applications, and safety upon consumers including current trends and future prospect of nutraceuticals will be included.

Effect of omega-3 on painful symptoms of patients with osteoarthritis of the synovial joints: systematic review and meta-analysis

OBJECTIVES

The aim of this study was to determine the effect of omega-3 on the painful symptomatology of osteoarthritis (OA) in synovial joints.

STUDY DESIGN

An electronic/manual search was conducted (2004-2019). Using pain as a primary outcome and stiffness/function and swelling as secondary outcomes, based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria, Consolidated Standards of Reporting Trials (CONSORT) reporting quality, and Cochrane/RoB-2 risk of bias assessment. Data were processed using RevMan v5.2 (Cochrane Collaboration).

RESULTS

Six randomized controlled trials were selected. The study population included 454 patients with OA. In 4 studies the pain in the intervention group presented significant pain reduction compared with the control group (mean difference = 22.89; 95% confidence interval, 3.37-42.42). Studies did not stablish the effective anti-inflammatory dose. The number of studies on stiffness/function and inflammation was low (n = 2). The evidence and degree of recommendation was 2B. The randomized controlled trials presented high clinical and methodological variability.

CONCLUSION

Omega-3 can significantly reduce painful symptoms in patients suffering from OA in synovial joints. However, the limited number of studies, range of doses, intervention periods, baseline characteristics of patients, and asymmetry in reporting bias, combined with the heterogeneity in the combined effect of the studies, offer low-quality evidence on which clinical guidance cannot be based.

Metformin and omega-3 fish oil elicit anti-inflammatory effects via modulation of some dysregulated micro RNAs expression and signaling pathways in experimental induced arthritis

OBJECTIVE

Rheumatoid arthritis is a progressive inflammatory disease with multiple dysfunctional intracellular signaling pathways that necessitate new approaches for its management. Hence, the study aimed to inspect the ability of the combination therapy of metformin and omega-3 to modulate different signaling pathways and micro RNAs such as (miR-155, miR-146a and miR-34) as new targets in order to mitigate adjuvant-induced arthritis and compare their effect to that of methotrexate.

METHODS

Fourteen days post adjuvant injection, Sprague-Dawley rats were treated orally with metformin (200 mg/kg/day) and/or omega-3 (300 mg/kg/day) or intraperitoneally with methotrexate (2 mg/kg/week) for 4 weeks.

RESULTS AND CONCLUSION

All drug treatments amended the arthrogram score and hind paw swelling as well as decreased serum tumor necrosis factor (TNF)-α and interleukin (IL)-1β levels. On the molecular level, all therapies activated phospho-5'adenosine monophosphate-activated protein kinase (p-AMPK) and protein phosphatase 2A (PP2A), while they inhibited phospho-mammalian target of rapamycin (p-mTOR), phospho-signal transducers and activators of transcription (p-STAT3), nuclear factor (NF)-κB p65 subunit, phosho38 mitogen-activated protein kinase (p38 MAPK) and phospho- c-Jun N-terminal kinase (p-JNK). In addition, they decreased the elevated expression level of miRNA-155, 146a and increased the expression level of miRNA-34 and they decreased the expression level of retinoic acid receptor related orphan receptor γT (RORγT) and increased that of fork head box P3 (FOXP3), correcting Th17/Treg cells balance. On most of the aforementioned parameters, the effect of the combination therapy was comparable to that of methotrexate, emphasizing that this combination possesses better additive anti-inflammatory effect than either drug when used alone. In addition, the combination was capable of normalizing the serum transaminases levels as compared to untreated group offering hepatoprotective effect and suggesting the possibility of its use as a replacement therapeutic strategy for MTX in rheumatoid arthritis.

Janus kinase inhibitors for treating active ankylosing spondylitis: a meta-analysis of randomized controlled trials

OBJECTIVE

In this study, we aimed to assess the safety and efficacy of Janus kinase (JAK) inhibitors in patients with ankylosing spondylitis (AS).

METHODS

We conducted a Bayesian network meta-analysis using direct and indirect data from randomized controlled trials (RCTs), and examined the safety and efficacy of JAK inhibitors in active AS patients exhibiting inadequate response or intolerance to two or more non-steroidal anti-inflammatory drugs (NSAIDs).

RESULTS

RCTs included a total of 406 patients (203 experimental subjects and 203 controls) from three studies on upadacitinib, filgotinib, and tofacitinib. Assessment of SpondyloArthritis International Society 20% improvement (ASAS20), ASAS40, and ASAS5/6 responses were significantly higher in the JAK inhibitor group than in the placebo group. Other efficacy outcomes, such as ASAS partial remission, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI50), Ankylosing Spondylitis Disease Activity Score (ASDAS), Spondyloarthritis Research Consortium of Canada (SPARCC) Magnetic Resonance Imaging (MRI) scores, and Bath Ankylosing Spondylitis Functional Index (BASFI) were also significantly higher in the JAK inhibitor group compared to the placebo group. The JAK inhibitors significantly improved disease activity (ASAS partial remission, BASDAI50, ASDAS), function (BASFI), and MRI outcomes (SPARCC MRI spine). However, the incidence of adverse events (AEs) and serious adverse events (SAEs), and the rate of withdrawal attributed to AEs did not differ between the JAK inhibitor and placebo groups.

CONCLUSION

JAK inhibitors were effective in active AS patients exhibiting an inadequate response or intolerance to two or more NSAIDs, without the risk of SAEs; this suggests that based on our data, studies are warranted to further investigate the use of JAK inhibitors for treating AS.

Diet as a Modulator of Intestinal Microbiota in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic immune-driven inflammatory disease characterised by synovial inflammation, leading to progressive cartilage and bone destruction, impacting patients' functional capacity and quality of life. Patients with RA have significant differences in gut microbiota composition when compared to controls. Intestinal dysbiosis influences the intestinal barrier strength, integrity and function, and diet is considered the main environmental factor impacting gut microbiota. Over the last few years, researchers have focused on the influence of single components of the diet in the modulation of intestinal microbiota in RA rather than whole dietary patterns. In this review, we focus on how the Mediterranean diet (MD), a whole dietary pattern, could possibly act as an adjuvant therapeutic approach, modulating intestinal microbiota and intestinal barrier function in order to improve RA-related outcomes. We also review the potential effects of particular components of the MD, such as n-3 polyunsaturated fatty acids (PUFAs), polyphenols and fibre.

1H-NMR-Based Analysis for Exploring Knee Synovial Fluid Metabolite Changes after Local Cryotherapy in Knee Arthritis Patients

Rehabilitation using cryotherapy has widely been used in inflammatory diseases to relieve pain and decrease the disease activity. The aim of this study was to explore the metabolite changes in inflammatory knee-joint synovial fluids following local cryotherapy treatment (ice or cold CO2). We used proton nuclear magnetic resonance (1H NMR) spectroscopy to assess the metabolite patterns in synovial fluid (SF) in patients with knee arthritis (n = 46) before (D0) and after (D1, 24 h later) two applications of local cryotherapy. Spectra from aqueous samples and organic extracts were obtained with an 11.75 Tesla spectrometer. The metabolite concentrations within the SF were compared between D1 and D0 using multiple comparisons with the application of a false discovery rate (FDR) adjusted at 10% for each metabolite. A total of 32 metabolites/chemical structures were identified including amino acids, organic acids, fatty acids or sugars. Pyruvate, alanine, citrate, threonine was significantly higher at D1 vs D0 (p < 0.05). Tyrosine concentration significantly decreases after cryotherapy application (p < 0.001). We did not observe any effect of gender and cooling technique on metabolite concentrations between D0 and D1 (p > 0.05). The present study provides new insight into a short-term effect of cold stimulus in synovial fluid from patients with knee arthritis. Our observations suggest that the increased level of metabolites involved in energy metabolism may explain the underlying molecular pathways that mediate the antioxidant and anti-inflammatory capacities of cryotherapy.

Effects of Nutritional Interventions in the Control of Musculoskeletal Pain: An Integrative Review

Food consumption has significant positive effects on an individual’s health status, including the reduction of symptoms associated with musculoskeletal pain. However, specific food groups indicated for the treatment of pain are not yet determined. Hence, this review aimed to analyze the effects of nutritional interventions with specific diets, oils and/or fatty acids, and foodstuffs in natura in the reduction of musculoskeletal pain. An integrative review was conducted in the following databases: Embase, PubMed, LILACS, and Google Scholar. Clinical trials written in English, Spanish, and Portuguese and published between 2000 and March 2020 were included in this review. Seventeen studies were included. Among these, a reduction of musculoskeletal pain with different types of nutritional interventions, such as vegan and Mediterranean diets and the consumption of blueberry, strawberry, passion fruit peel extract, argan oil, fish oil (omega-3), olive oil, and undenatured type II collagen and vitamin D gel capsules, was observed in 14 studies. Eight studies evaluated the profiles of several inflammatory markers, and of these, decreased interleukin (IL)-6, IL-1β, and tumor necrosis factor-α levels were observed in two studies. This review suggests that different nutritional interventions with specific diets, oils and/or fatty acids, and foodstuffs in natura reduce musculoskeletal pain, specifically in adults with osteoarthritis. Besides pain improvement, nutritional interventions, including the consumption of strawberry and vitamin D gel capsules, decrease the levels of several inflammatory markers.

Effect of inorganic carbon limitation on the conversion of organic carbon to total fatty acids by Monodus subterraneus

Traditional autotrophic microalgae exhibit low rates of organic carbon assimilation and conversion to useful compounds when switching to mixotrophic or heterotrophic growth. The goal of this study was to investigate the effect of inorganic carbon limitation on the efficiency of organic carbon (glycerol) assimilation and conversion to total fatty acids (TFAs) or the long-chain polyunsaturated fatty acid eicosapentaenoic acid (EPA). An oleaginous Monodus subterraneus was selected and six cultivation conditions were set, including Autotrophy-no aeration, Autotrophy-aeration, Mixotrophy-no aeration, Mixotrophy-no aeration & no Na₂CO₃, Mixotrophy-aeration, and Heterotrophy. The results showed M. subterraneus could utilize glycerol and grow under mixotrophic condition, while it was not occurred under heterotrophy. Superiority of mixotrophy to autotrophy on biomass productivity was more obvious under inorganic carbon limitation (no aeration or no Na₂CO₃) than inorganic carbon supply (aeration and existing Na₂CO₃ in the medium). CO₂ limitation (no aeration) decreased content (of dry weight) and production (in medium) of TFAs, which was not evident in mixotrophy. CO₂ limitation and inorganic carbon substrate stress largely improved the COD yield of TFAs and EPA under mixotrophic condition. TFA yield (%COD) under Mixotrophy-no aeration & no Na₂CO₃ was maximum (22.82%), and was almost two-fold higher than that under Mixotrophy-no aeration and nearly three-fold higher than that with Mixotrophy-aeration. EPA yield (% COD) under mixotrophy-no aeration & no Na₂CO₃ was maximum (6.58%). These results suggested that inorganic carbon limitation is a potentially useful method to enhance conversion of organic carbon to TFAs. Furthermore, the results suggest an application to obtain high value compounds (TFAs or EPA) combined with a high assimilation rate of waste glycerol from biodiesel and epichlorohydrin production by microalgae.

Ideal food pyramid for patients with rheumatoid arthritis: A narrative review

Emerging literature suggests that diet plays an important modulatory role in rheumatoid arthritis (RA) because diet is an environmental factor that affects inflammation, antigen presentation, antioxidant defense mechanisms and gut microbiota. Patients with RA frequently ask their doctors about which diets to follow, and even in the absence of advice from their physicians, many patients are undertaking various dietary interventions. Given this background, the aim of this review is to evaluate the evidence to date regarding the ideal dietary approach for management of RA in order to reduce the counteracting inflammation, and to construct a food pyramid for patients with RA. The pyramid shows that carbohydrates should be consumed every day (3 portions of whole grains, preferably gluten free), together with fruits and vegetables (5 portions; among which fruit, berries and citrus fruit are to be preferred, and among the vegetables, green leafy ones.), light yogurt (125 ml), skim milk (200 ml), 1 glass (125 ml) of wine and extra virgin olive oil; weekly, fish (3 portions), white meat (3 portions), legumes (2 portions) eggs (2 portions), seasoned cheeses (2 portions), and red or processed meats (once a week). At the top of the pyramid, there are two pennants: one green means that subjects with RA need some personalized supplementation (vitamin D and omega 3) and one red means that there are some foods that are banned (salt and sugar). The food pyramid allows patients to easily figure out what to eat.

Nutraceuticals: Reviewing their Role in Chronic Disease Prevention and Management

Over half the adult population in many Western countries consume nutraceuticals because of their purported therapeutic benefits, accessibility and convenience. Several studies have demonstrated that they may also serve as a useful adjunct to pharmaceuticals to better manage chronic conditions or offset negative side effects. Individuals are advised to consult their physician before using nutraceuticals, but this advice is often overlooked. Thus, the community pharmacist plays an increasingly important role in assisting consumers with selecting a nutraceutical that is safe and for which there is evidence of therapeutic efficacy. Therefore, the aim of this review is to summarise the clinical evidence, safety and purported mechanisms of action for selected nutraceuticals in the management of chronic diseases, including obesity, diabetes, hypertension, hypercholesterolemia and inflammatory-based diseases.