Bio-optimized Curcuma longa extract is efficient on knee osteoarthritis pain: a double-blind multicenter randomized placebo controlled three-arm study

Phytochemicals against Osteoarthritis by Inhibiting Apoptosis

Osteoarthritis (OA) is a chronic joint disease that causes pathological changes in articular cartilage, synovial membrane, or subchondral bone. Conventional treatments for OA include surgical and non-surgical methods. Surgical treatment is suitable for patients in the terminal stage of OA. It is often the last choice because of the associated risks and high cost. Medication of OA mainly includes non-steroidal anti-inflammatory drugs, analgesics, hyaluronic acid, and cortico-steroid anti-inflammatory drugs. However, these drugs often have severe side effects and cannot meet the needs of patients. Therefore, safe and clinically appropriate long-term treatments for OA are urgently needed. Apoptosis is programmed cell death, which is a kind of physiologic cell suicide determined by heredity and conserved by evolution. Inhibition of apoptosis-related pathways has been found to prevent and treat a variety of diseases. Excessive apoptosis can destroy cartilage homeostasis and aggravate the pathological process of OA. Therefore, inhibition of apoptosis-related factors or signaling pathways has become an effective means to treat OA. Phytochemicals are active ingredients from plants, and it has been found that phytochemicals can play an important role in the prevention and treatment of OA by inhibiting apoptosis. We summarize preclinical and clinical studies of phytochemicals for the treatment of OA by inhibiting apoptosis. The results show that phytochemicals can treat OA by targeting apoptosis-related pathways. On the basis of improving some phytochemicals with low bioavailability, poor water solubility, and high toxicity by nanotechnology-based drug delivery systems, and at the same time undergoing strict clinical and pharmacological tests, phytochemicals can be used as a potential therapeutic drug for OA and may be applied in clinical settings.

Efficacy and safety of curcumin therapy for knee osteoarthritis: A Bayesian network meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Curcumin, a polyphenolic compound extracted from turmeric (Curcuma longa L.), is widely used in traditional Chinese medicine to treat osteoarthritis and rheumatoid arthritis. Clinical and experimental studies show that curcuminoid formulations have considerable clinical application value in the treatment of knee osteoarthritis (KOA).

AIM OF THE STUDY

To evaluate the efficacy and safety of curcumin, both alone and in combination with other drugs, in KOA treatment through a Bayesian network meta-analysis (NMA).

METHODS

We searched PubMed, Embase and Cochrane Library for randomized controlled trials of curcumin for KOA treatment. The time range of the search was from the establishment of each database to April 26, 2023. The NMAs of outcome indicators were all performed using a random-effects model. NMAs were calculated and graphed in R using MetaInsight and Stata 140 software. Measurement data were represented by the mean difference (MD), while count data were represented by the odds ratio (OR); the 95% confidence interval (CI) of each effect size was also calculated.

RESULTS

This study included 23 studies from 7 countries, including 2175 KOA patients and 6 interventions. The NMA results showed that compared with placebo, curcumin significantly reduced the visual analogue scale pain score (MD = -1.63, 95% CI: -2.91 to -0.45) and total WOMAC score (MD = -18.85, 95% CI: -29.53 to -8.76). Compared with placebo, curcumin (OR = 0.17, 95% CI: 0.08 to 0.36), curcumin + NSAIDs (OR = 0.01, 95% CI: 0.00 to 0.13) and NSAIDs (OR = 0.11, 95% CI: 0.02 to 0.47) reduced the use of rescue medication. Compared with NSAIDs, curcumin (OR = 0.51, 95% CI: 0.25 to 0.94) and curcumin + NSAIDs (OR = 0.23, 95% CI: 0.06 to 0.9) had a reduced incidence of adverse reactions. The surface under the cumulative ranking curve results indicated that curcumin monotherapy, curcumin + chondroprotective agents, and curcumin + NSAIDs have good clinical value in KOA treatment.

CONCLUSIONS

Curcumin, either alone or in combination with other treatments, is considered to have good clinical efficacy and safety in KOA treatment. Drug combinations containing curcumin may have the dual effect of enhancing efficacy and reducing adverse reactions, but this possibility still needs to be confirmed by further clinical and basic research.

Natural products in osteoarthritis treatment: bridging basic research to clinical applications

Osteoarthritis (OA) is the most prevalent degenerative musculoskeletal disease, severely impacting the function of patients and potentially leading to disability, especially among the elderly population. Natural products (NPs), obtained from components or metabolites of plants, animals, microorganisms etc., have gained significant attention as important conservative treatments for various diseases. Recently, NPs have been well studied in preclinical and clinical researches, showing promising potential in the treatment of OA. In this review, we summed up the main signaling pathways affected by NPs in OA treatment, including NF-κB, MAPKs, PI3K/AKT, SIRT1, and other pathways, which are related to inflammation, anabolism and catabolism, and cell death. In addition, we described the therapeutic effects of NPs in different OA animal models and the current clinical studies in OA patients. At last, we discussed the potential research directions including in-depth analysis of the mechanisms and new application strategies of NPs for the OA treatment, so as to promote the basic research and clinical transformation in the future. We hope that this review may allow us to get a better understanding about the potential bioeffects and mechanisms of NPs in OA therapy, and ultimately improve the effectiveness of NPs-based clinical conservative treatment for OA patients.

Bioactives and their roles in bone metabolism of osteoarthritis: evidence and mechanisms on gut-bone axis

Bioactives significantly modify and maintain human health. Available data suggest that Bioactives might play a beneficial role in chronic inflammatory diseases. Although promised, defining their mechanisms and opting to weigh their benefits and limitations is imperative. Detailed mechanisms by which critical Bioactives, including probiotics and prebiotics such as dietary lipids (DHA, EPA, alpha LA), vitamin D, polysaccharides (fructooligosaccharide), polyphenols (curcumin, resveratrol, and capsaicin) potentially modulate inflammation and bone metabolism is limited. Certain dietary bioactive significantly impact the gut microbiota, immune system, and pain response via the gut-immune-bone axis. This narrative review highlights a recent update on mechanistic evidence that bioactive is demonstrated demonstrated to reduce osteoarthritis pathophysiology.

Natural anti-inflammatory products for osteoarthritis: From molecular mechanism to drug delivery systems and clinical trials

Osteoarthritis (OA) is a degenerative joint disease that affects millions globally. The present nonsteroidal anti-inflammatory drug treatments have different side effects, leading researchers to focus on natural anti-inflammatory products (NAIPs). To review the effectiveness and mechanisms of NAIPs in the cellular microenvironment, examining their impact on OA cell phenotype and organelles levels. Additionally, we summarize relevant research on drug delivery systems and clinical randomized controlled trials (RCTs), to promote clinical studies and explore natural product delivery options. English-language articles were searched on PubMed using the search terms "natural products," "OA," and so forth. We categorized search results based on PubChem and excluded "natural products" which are mix of ingredients or compounds without the structure message. Then further review was separately conducted for molecular mechanisms, drug delivery systems, and RCTs later. At present, it cannot be considered that NAIPs can thoroughly prevent or cure OA. Further high-quality studies on the anti-inflammatory mechanism and drug delivery systems of NAIPs are needed, to determine the appropriate drug types and regimens for clinical application, and to explore the combined effects of different NAIPs to prevent and treat OA.

Sources, morphology, phytochemistry, pharmacology of Curcumae Longae Rhizoma, Curcumae Radix, and Curcumae Rhizoma: a review of the literature

Curcumae Longae Rhizoma (turmeric), Curcumae Radix and Curcumae Rhizoma are derived from the Curcuma species, and have gradually become three of the most commonly used medicinal herbs in China due to their different origins, processing methods and medicinal part. These three herbs have certain similarities in morphology, chemical composition, and pharmacological effects. All three of these herbs contain curcuminoids and volatile oil compounds, which exhibit anti-inflammatory, anti-tumor, antioxidant, and neuroprotective properties, although modern clinical applications have their own requirements. At present, there is no systematic guidelines for the clinical application of these three of Curcuma species; consequently, there is a high risk of unwanted phenomena associated with the mixing and indiscriminate use of these herbs. In this review, we focus predominantly on morphology, chemical composition, and the pharmacological activity of these three Curcuma herbs and summarize the current status of research in this field. Our goal is to provide a better understanding of clinical value of these Curcuma species so that we can provide reference guidelines for their further development, utilization and rational clinical application.

The extract of Curcumae Longae Rhizoma suppresses angiogenesis via VEGF-induced PI3K/Akt-eNOS-NO pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Curcumae Longae Rhizoma (CLR) is a safe natural herbal medicine, and which has been widely used for centuries as functional food and health products, but its effects on angiogenesis and related underlying mechanism remain unclear.

AIM OF THE STUDY

The abnormal angiogenesis is closely related with various diseases, and therefore the precise control of angiogenesis is of great importance. The well-known angiogenic factor, vascular endothelial growth factor (VEGF), mediates angiogenesis and induces multiple signalling pathways via binding to VEGF receptor (VEGFR). The attenuation of VEGF-triggered angiogenic-related signalling pathways may relieve various diseases through suppression of angiogenesis. Here, we aimed to elucidate that CLR extract could exert striking anti-angiogenic activities both in vitro and in vivo.

MATERIALS AND METHODS

The viability of human umbilical vascular endothelial cell (HUVEC) was examined by LDH and MTT assays. Migrative and invasive ability of the endothelial cells were independently evaluated by wound healing and transwell assays. The activities of CLR extract on in vitro angiogenesis was tested by tube formation assay. In vivo vascularization was determined by using zebrafish embryo model in the present of CLR extract. Western blotting was applied to determine the phosphorylated levels of VEGFR2, PI3K, AKT and eNOS. Besides, the levels of nitric oxide (NO) and reactive oxygen species (ROS) were separately evaluated by Griess assay and 2'7'-dichlorofluorescein diacetate reaction. In addition, the cell migrative ability of cancer cell was estimated by using cultured human colon carcinoma cells (HT-29 cell line), and immunofluorescence assay was applied to evaluate the effect of CLR extract on nuclear translocation of NF-κB p65 subunit in the VEGF-treated HT-29 cultures.

RESULTS

CLR extract significantly suppressed a series of VEGF-mediated angiogenic responses, including endothelial cell proliferation, migration, invasion, and tube formation. Moreover, CLR extract reduced in vivo sub-intestinal vessel formation in zebrafish embryo model. Mechanistically, the extract of CLR attenuated the VEGF-triggered signalling, as demonstrated by decreased level of phosphorylated VEGFR2 and subsequently inactivated its downstream regulators, e.g. phospho-PI3K, phospho-AKT and phospho-eNOS. The production of NO and formation of ROS were markedly inhibited in HUVECs. Furthermore, CLR extract suppressed cell migration and NF-κB translocation in cultured HT-29 cells.

CONCLUSIONS

These preclinical findings demonstrate that the extract of CLR remarkably attenuates angiogenesis and which has great potential as a natural drug candidate with excellent anti-angiogenic activity.

[Recommendations of the committee on complementary medicine and nutrition in ayurvedic medicine, homeopathy, nutrition and Mediterranean diet]

Methods of complementary and alternative medicine (CAM) are appealing for many patients with rheumatic diseases. The scientific data are currently characterized by a large number of publications that stand in contrast to a remarkable shortage of valid clinical studies. The applications of CAM procedures are situated in an area of conflict between efforts for an evidence-based medicine and high-quality therapeutic concepts on the one hand and ill-founded or even dubious offers on the other hand. In 2021 the German Society of Rheumatology (DGRh) launched a committee for CAM and nutrition, which aims to collect and to evaluate the current evidence for CAM applications and nutritional medical interventions in rheumatology, in order to elaborate recommendations for the clinical practice. The current article presents recommendations for nutritional interventions in the rheumatological routine for four areas: nutrition, Mediterranean diet, ayurvedic medicine and homeopathy.

Molecular Basic of Pharmacotherapy of Cytokine Imbalance as a Component of Intervertebral Disc Degeneration Treatment

Intervertebral disc degeneration (IDD) and associated conditions are an important problem in modern medicine. The onset of IDD may be in childhood and adolescence in patients with a genetic predisposition. With age, IDD progresses, leading to spondylosis, spondylarthrosis, herniated disc, spinal canal stenosis. One of the leading mechanisms in the development of IDD and chronic back pain is an imbalance between pro-inflammatory and anti-inflammatory cytokines. However, classical therapeutic strategies for correcting cytokine imbalance in IDD do not give the expected response in more than half of the cases. The purpose of this review is to update knowledge about new and promising therapeutic strategies based on the correction of the molecular mechanisms of cytokine imbalance in patients with IDD. This review demonstrates that knowledge of the molecular mechanisms of the imbalance between pro-inflammatory and anti-inflammatory cytokines may be a new key to finding more effective drugs for the treatment of IDD in the setting of acute and chronic inflammation.

Role of Turmeric and Curcumin in Prevention and Treatment of Chronic Diseases: Lessons Learned from Clinical Trials

Turmeric (Curcuma longa) has been used for thousands of years for the prevention and treatment of various chronic diseases. Curcumin is just one of >200 ingredients in turmeric. Almost 7000 scientific papers on turmeric and almost 20,000 on curcumin have been published in PubMed. Scientific reports based on cell culture or animal studies are often not reproducible in humans. Therefore, human clinical trials are the best indicators for the prevention and treatment of a disease using a given agent/drug. Herein, we conducted an extensive literature survey on PubMed and Scopus following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The keywords "turmeric and clinical trials" and "curcumin and clinical trials" were considered for data mining. A total of 148 references were found to be relevant for the key term "turmeric and clinical trials", of which 70 were common in both PubMed and Scopus, 44 were unique to PubMed, and 34 were unique to Scopus. Similarly, for the search term "curcumin and clinical trials", 440 references were found to be relevant, of which 70 were unique to PubMed, 110 were unique to Scopus, and 260 were common to both databases. These studies show that the golden spice has enormous health and medicinal benefits for humans. This Review will extract and summarize the lessons learned about turmeric and curcumin in the prevention and treatment of chronic diseases based on clinical trials.

Curcuma as an anti-inflammatory component in treating osteoarthritis

Osteoarthritis (OA) is nowadays the most common musculoskeletal progressive condition. In recent decades, incidence and prevalence of OA have increased significantly. It is estimated that the prevalence of OA among adults older than 60 is 12%, affecting about 240 million people globally. The cause has not been fully elucidated, and therefore, there is no cure at the moment. It is a multifactorial degenerative disease with an inflammatory component mediated by numerous proinflammatory and anti-inflammatory cytokines, chemokines, and growth factors. OA is not yet fully understood; therefore, therapeutic interventions are aimed primarily at reducing symptoms and slowing the progression of joint destruction. Of the therapeutic options available, the most often prescribed are nonsteroidal antirheumatic drugs, which have numerous side effects. Therefore, a need for a safe, effective substance is differentiated, which will be used in adjuvant treatment, but also in disease prevention, and which will comparatively have no or fewer side effects. One such substance is curcumin, a hydrophobic polyphenol that forms the active component of the rhizome of the Curcuma longa plant. Several studies have shown its potent antioxidant and anti-inflammatory effect, non-toxicity, and safety at high daily doses. In addition to blocking chondrocyte apoptosis, curcumin also blocks the expression of cyclooxygenase, prostaglandin E-2 and proinflammatory cytokines in chondrocytes, potentially alleviating symptomatic diseases. Although there are significant variations in quality, methodology, and research results conducted on curcumin efficiency in OA treatment, curcumin is primarily recommended as systematic short-term and medium-term adjuvant therapy that reduces inflammatory biochemical factors. Reducing inflammation leads to better pain regulation and improved joint function, significantly reducing standard prescribed doses of drugs. The most researched daily doses of curcumin intake are 1000-2000 mg/day, which would also be the doses that most of the authors recommend. Further research is needed to determine the preventive role of curcumin in the pathogenesis of OA, the effects of long-term usage of curcumin in preventive purposes and treatment of osteoarthritis, as well as to determine optimal therapeutic dosages.

Curcumin Supplementation and Human Disease: A Scoping Review of Clinical Trials

Medicinal properties of turmeric (Curcuma longa L.), a plant used for centuries as an anti-inflammatory, are attributed to its polyphenolic curcuminoids, where curcumin predominates. Although "curcumin" supplements are a top-selling botanical with promising pre-clinical effects, questions remain regarding biological activity in humans. To address this, a scoping review was conducted to assess human clinical trials reporting oral curcumin effects on disease outcomes. Eight databases were searched using established guidelines, yielding 389 citations (from 9528 initial) that met inclusion criteria. Half focused on obesity-associated metabolic disorders (29%) or musculoskeletal disorders (17%), where inflammation is a key driver, and beneficial effects on clinical outcomes and/or biomarkers were reported for most citations (75%) in studies that were primarily double-blind, randomized, and placebo-controlled trials (77%, D-RCT). Citations for the next most studied disease categories (neurocognitive [11%] or gastrointestinal disorders [10%], or cancer [9%]), were far fewer in number and yielded mixed results depending on study quality and condition studied. Although additional research is needed, including systematic evaluation of diverse curcumin formulations and doses in larger D-RCT studies, the preponderance of current evidence for several highly studied diseases (e.g., metabolic syndrome, osteoarthritis), which are also clinically common, are suggestive of clinical benefits.

Latest insights in disease-modifying osteoarthritis drugs development

Osteoarthritis (OA) is a prevalent and severely debilitating disease with an unmet medical need. In order to alleviate OA symptoms or prevent structural progression of OA, new drugs, particularly disease-modifying osteoarthritis drugs (DMOADs), are required. Several drugs have been reported to attenuate cartilage loss or reduce subchondral bone lesions in OA and thus potentially be DMOADs. Most biologics (including interleukin-1 (IL-1) and tumor necrosis factor (TNF) inhibitors), sprifermin, and bisphosphonates failed to yield satisfactory results when treating OA. OA clinical heterogeneity is one of the primary reasons for the failure of these clinical trials, which can require different therapeutic approaches based on different phenotypes. This review describes the latest insights into the development of DMOADs. We summarize in this review the efficacy and safety profiles of various DMOADs targeting cartilage, synovitis, and subchondral bone endotypes in phase 2 and 3 clinical trials. To conclude, we summarize the reasons for clinical trial failures in OA and suggest possible solutions.

The effects of antioxidants on knee osteoarthritis: A systematic review and meta-analysis

Objective

Knee osteoarthritis (KOA) is one of the growing health problems with a considerable burden. With recent research on the possible effectiveness of antioxidants in the remission of KOA symptoms, a systematic review and meta-analysis was required to confirm this hypothesis.

Design

Literature studies were searched on the most comprehensive databases such as PubMed, International Scientific Indexing, and Scopus, with no language and time restrictions. On 17 July 2021, a search strategy was developed based on the roots of "osteoarthritis (OA)" and "antioxidants," with no time or language limitations. As the primary outcome, pain was evaluated based on all indicators for evaluating pain [e.g., Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain scores, the visual analog scale (VAS), and the numerical rating scale (NRS)]. The symptoms and functions of KOA and quality of life (QOL) were also considered as secondary outcomes, each of which was measured and reported by the corresponding instrument in the studies. To measure the changes in pain, symptoms, and functions of participants, we included randomized controlled trials with a placebo control or other medical therapeutic interventions. Publication bias was assessed using Begg's funnel plot and Egger's regression test, which was deemed to be statistically significant at 0.1, and the results were checked by the trim-and-fill test.

Results

After refinement, data were extracted from 31 documents from 7,698 primary searched papers. Using the VAS as a reliable psychometric measuring instrument, the present study revealed that a significant difference in the characteristics of disease-related symptoms of patients with KOA was reached after antioxidant therapy (standardized mean difference (SMD): 0.467, 95% confidence interval (CI): 0.303-0.632, p < 0.0001). The results reported by WOMAC confirmed no significant difference in the combined score, difficulty score, pain score, and stiffness score.

Conclusion

As the first comprehensive systematic review of the association between antioxidant supplementation and KOA, this study showed that antioxidants can decrease disease-related symptoms in patients with KOA. The results can be useful for health policy decisions and future related studies.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022351060, identifier: CRD42022351060.

Curcuma longa and Boswellia serrata extract combination for hand osteoarthritis: an open-label pre-post trial

CONTEXT

Osteoarthritis (OA) of the hand is a common painful musculoskeletal disorder with no cure. There is a need for an efficient and safe treatment to relieve OA pain.

OBJECTIVE

To investigate the effects of a Curcuma longa and Boswellia serrata food supplement in addition to standard care on hand pain.

MATERIALS AND METHODS

This open-label, non-controlled, post-observational study was based on 232 patients suffering from hand pain with or without joint deformity. Patients received a medical prescription for a three-month treatment with a food supplement containing 89 mg of C. longa dry extract, 120 mg of B. serrata resin, and 1.8 µg vitamin D. Pain was evaluated on a 10-point visual analog scale (VAS). The number of painful hand joints, patient satisfaction, nonsteroidal anti-inflammatory drugs intake, and side effects were also recorded.

RESULTS

Baseline pain intensity (regression coefficient ± SE: -0.19 ± 0.01, p < 0.0001) and the number of painful joints (regression coefficient ± SE: -0.022 ± 0.0029, p < 0.0001) decreased significantly throughout the 3 months treatment period. NSAIDs intake and topical drug application were significantly decreased by 64% (p < 0.0001) and 79% (p < 0.0001) after 12 weeks, respectively. Only 3/239 (1.3%) patients reported side effects probably related to the product. 80.3% were satisfied with the treatment and 75.5% wished to continue treatment.

CONCLUSION

This is the first clinical trial showing that C. longa and B. serrata resin can relieve symptoms in patients with hand osteoarthritis. The study provides useful information for the design of a clinical trial including a broader population.

Efficacy and safety of curcuminoids alone in alleviating pain and dysfunction for knee osteoarthritis: a systematic review and meta-analysis of randomized controlled trials

Background

Curcuminoids (CURs) are the principal ingredients of Curcuma longa L. [Zingiberaceae] (CL)—an herbal plant used in east Asia to alleviate pain and inflammation. Thus far, the therapeutic effects of CURs for knee osteoarthritis (OA) uncovered by multiple reviews remained uncertain due to broadly involving trials with different agents-combined or CURs-free interventions. Therefore, we formed stringent selection criteria and assessment methods to summarize current evidence on the efficacy and safety of CURs alone in the treatment of knee OA.

Methods

A series of databases were searched for randomized controlled trials (RCTs) evaluating the efficacy and safety of CURs for knee OA. Clinical outcomes were evaluated using meta-analysis and the minimum clinically important difference (MCID) for both statistical and clinical significance.

Results

Fifteen studies with 1670 patients were included. CURs were significantly more effective than placebo in the improvements of VAS for pain ( WMD: − 1.77, 95% CI: − 2.44 to − 1.09), WOMAC total score ( WMD: − 7.06, 95% CI: − 12.27 to − 1.84), WOMAC pain score ( WMD: − 1.42, 95% CI: − 2.41 to − 0.43), WOMAC function score ( WMD: − 5.04, 95% CI: − 7.65 to − 2.43), and WOMAC stiffness score ( WMD: − 0.54, 95% CI: − 1.03 to − 0.05). Meanwhile, CURs were not inferior to NSAIDs in the improvements of pain- and function-related outcomes. Additionally, CURs did not significantly increase the incidence of adverse events (AEs) compared with placebo ( RR: 1.03, 95% CI: 0.69 to 1.53, P = 0.899, I² = 23.7%) and NSAIDs (RR: 0.71 0.65, 95% CI: 0.57 0.41 to 0.90 1.03).

Conclusions

CURs alone can be expected to achieve considerable analgesic and functional promotion effects for patients with symptomatic knee OA in short term, without inducing an increase of adverse events. However, considering the low quality and substantial heterogeneity of present studies, a cautious and conservative recommendation for broader clinical use of CURs should still be made. Further high-quality studies are necessary to investigate the impact of different dosages, optimization techniques and administration approaches on long-term safety and efficacy of CURs, so as to strengthen clinical decision making for patients with symptomatic knee OA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-022-03740-9.

Potential complementary and/or synergistic effects of curcumin and boswellic acids for management of osteoarthritis

For several thousand years (~4000) Boswellia serrata and Curcuma longa have been used in Aryuvedic medicine for treatment of various illnesses, including asthma, peptic ulcers, and rheumatoid arthritis, all of which are mediated through pathways associated with inflammation and pain. Although the in vivo pharmacology of both these natural ingredients is difficult to study because of poor bioavailability, in vitro data suggest that both influence gene expression mediated through nuclear factor kappa B (NF-κB). Therefore, the activity of pathways associated with inflammation (including NF-κB and lipoxygenase- and cyclooxygenase-mediated reduction in leukotrienes/prostaglandins) and those involved in matrix degradation and apoptosis are reduced, resulting in a reduction in pain. Additive activity of boswellic acids and curcumin was observed in preclinical models and synergism was suggested in clinical trials for the management of osteoarthritis (OA) pain. Overall, studies of these natural ingredients, alone or in combination, revealed that these extracts relieved pain from OA and other inflammatory conditions. This may present an opportunity to improve patient care by offering alternatives for patients and physicians, and potentially reducing nonsteroidal anti-inflammatory or other pharmacologic agent use. Additional research is needed on the effects of curcumin on the microbiome and the influence of intestinal metabolism on the activity of curcuminoids to further enhance formulations to ensure sufficient anti-inflammatory and antinociceptive activity. This narrative review includes evidence from in vitro and preclinical studies, and clinical trials that have evaluated the mechanism of action, pharmacokinetics, efficacy, and safety of curcumin and boswellic acids individually and in combination for the management of OA pain.

Curcuma longa and Boswellia serrata Extracts Modulate Different and Complementary Pathways on Human Chondrocytes In Vitro: Deciphering of a Transcriptomic Study

Objectives:Curcuma longa (CL) and Boswellia serrata (BS) extracts are used to relieve osteoarthritis symptoms. The aim of this in vitro study was to investigate their mechanisms of action at therapeutic plasmatic concentrations on primary human osteoarthritic (OA) chondrocytes.

Methods: BS (10–50 μg/ml) and CL (0.4–2 μg/ml corresponding to 1–5 µM of curcumin) were evaluated separately or in combination on primary chondrocytes isolated from 17 OA patients and cultured in alginate beads. Ten patients were used for RNA-sequencing analysis. Proteomic confirmation was performed either by immunoassays in the culture supernatant or by flow cytometry for cell surface markers after 72 h of treatment.

Results: Significant gene expression modifications were already observed after 6 h of treatment at the highest dose of CL (2 μg/ml) while BS was significantly effective only after 24 h of treatment irrespective of the concentration tested. The most over-expressed genes by CL were anti-oxidative, detoxifying, and cytoprotective genes involved in the Nrf2 pathway. Down-regulated genes were principally pro-inflammatory cytokines and chemokines. Inversely, BS anti-oxidant/detoxifying activities were related to the activation of Nrf1 and PPARα pathways. BS anti-inflammatory effects were associated with the increase in GDF15, decrease in cholesterol cell intake and fatty acid metabolism-involved genes, and down-regulation of Toll-like receptors (TLRs) activation. Similar to CL, BS down-regulated ADAMTS1, 5, and MMP3, 13 genes expression. The combination of both CL and BS was significantly more effective than CL or BS alone on many genes such as IL-6, CCL2, ADAMTS1, and 5.

Conclusion: BS and CL have anti-oxidative, anti-inflammatory, and anti-catabolic activities, suggesting a protective effect of these extracts on cartilage. Even if they share some mechanism of action, the two extracts act mainly on distinct pathways, and with different time courses, justifying their association to treat osteoarthritis.

Engineering of MSC-Derived Exosomes: A Promising Cell-Free Therapy for Osteoarthritis

Osteoarthritis (OA) is characterized by progressive cartilage degeneration with increasing prevalence and unsatisfactory treatment efficacy. Exosomes derived from mesenchymal stem cells play an important role in alleviating OA by promoting cartilage regeneration, inhibiting synovial inflammation and mediating subchondral bone remodeling without the risk of immune rejection and tumorigenesis. However, low yield, weak activity, inefficient targeting ability and unpredictable side effects of natural exosomes have limited their clinical application. At present, various approaches have been applied in exosome engineering to regulate their production and function, such as pretreatment of parental cells, drug loading, genetic engineering and surface modification. Biomaterials have also been proved to facilitate efficient delivery of exosomes and enhance treatment effectiveness. Here, we summarize the current understanding of the biogenesis, isolation and characterization of natural exosomes, and focus on the large-scale production and preparation of engineered exosomes, as well as their therapeutic potential in OA, thus providing novel insights into exploring advanced MSC-derived exosome-based cell-free therapy for the treatment of OA.

Efficacy and Safety of Curcumin and Curcuma longa Extract in the Treatment of Arthritis: A Systematic Review and Meta-Analysis of Randomized Controlled Trial

Background

Modern pharmacological research found that the chemical components of Curcuma longa L. are mainly curcumin and turmeric volatile oil. Several recent randomized controlled trials (RCT) have shown that curcumin improves symptoms and inflammation in patients with arthritis.

Methods

Pubmed, Cochran Library, CNKI, and other databases were searched to collect the randomized controlled trials (RCTs). Then, the risk of bias of RCTs were assessed and data of RCTs were extracted. Finally, RevMan 5.3 was utilized for meta-analysis.

Results

Twenty-nine (29) RCTs involving 2396 participants and 5 types of arthritis were included. The arthritis included Ankylosing Spondylitis (AS), Rheumatoid Arthritis (RA), Osteoarthritis (OA), Juvenile idiopathic arthritis (JIA) and gout/hyperuricemia. Curcumin and Curcuma longa Extract were administered in doses ranging from 120 mg to 1500 mg for a duration of 4-36 weeks. In general, Curcumin and Curcuma longa Extract showed safety in all studies and improved the severity of inflammation and pain levels in these arthritis patients. However, more RCTs are needed in the future to elucidate the effect of Curcumin and Curcuma longa Extract supplementation in patients with arthritis, including RA, OA, AS and JIA.

Conclusion

Curcumin and Curcuma longa Extract may improve symptoms and inflammation levels in people with arthritis. However, due to the low quality and small quantity of RCTs, the conclusions need to be interpreted carefully.

Rubus idaeus extract improves symptoms in knee osteoarthritis patients: results from a phase II double-blind randomized controlled trial

Background

Osteoarthritis (OA) is the most frequent cause of disability in elderly people. In daily practice, the main objective of the physician is to reduce patient symptoms using treatments without adverse effects. However, the most prescribed treatment to manage OA symptoms remains nonsteroidal anti-inflammatory drugs which are associated with severe adverse effects. Therefore, we need a safe alternative to managing OA. One candidate is Rubus idaeus leaf extracts known to inhibit inflammatory responses.

Objective

This study aimed to evaluate the effects of a 12-weeks intervention with an ethanolic extract from Rubus idaeus leaf on symptoms of knee osteoarthritis.

Method

The study was a randomized, double-blind, placebo-controlled, monocentric trial of 198 participants with femorotibial osteoarthritis. Participants were randomized equally to receive one daily during 3 months either 1 capsule of Rubus idaeus leaf extract 400 mg, 1 capsule of Rubus idaeus leaf extract 200 mg, or 1 capsule of placebo. The participants were assessed at baseline and after one and three months of treatment. The primary endpoint was an absolute change of the Western Ontario McMaster osteoarthritis index (WOMAC) pain subscale. The secondary endpoints were WOMAC global score, stiffness and function sub-scales, knee pain VAS score at walking, the Short Form (SF)-36, the Short Physical Performance Battery (SPPB), the 20-m walk test, and the International Physical Activity Questionnaire (IPAQ) and Outcome Measures in Rheumatology Clinical Trials and Osteoarthritis Research Society International (OMERACT-OARSI) responders rate. Statistical analyses were conducted on the intent-to-treat (ITT) population.

Results

In the Intention-to-treat population, WOMAC pain was not significantly modified by Rubus idaeus leaf extract compared to placebo. In contrast, Rubus idaeus leaf extract 400 mg after 12 weeks of treatment significantly reduced pain measured by the VAS. The mean pain decrease induced by Rubus ideaus leaf extract was over -7 mm which is clinically relevant and reached a clinically statistical difference compared to placebo with the highest dose. Rubus Ideaus was not significantly more efficient than the placebo on WOMAC global score, stiffness, and physical function subscores, IPAQ, SF-36, walking distance in treadmill test, SPPB, and evaluation of associated treatments needed to manage OA.

Conclusion

Rubus idaeus leaf extract was well tolerated and effective to relieve pain in a patient with knee osteoarthritis.

Trial registration

NCT03703024 (11/10/2018).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05612-2.

A Meta-Analysis of the Impact of Nutritional Supplementation on Osteoarthritis Symptoms

Conflicting evidence exists concerning the effects of nutrient intake in osteoarthritis (OA). A systematic literature review and meta-analysis were performed using PubMed, EMBASE, and Cochrane Library up to November 2021 to assess the effects of nutrients on pain, stiffness, function, quality of life, and inflammation markers. We obtained 52 references including 50 on knee OA. Twelve studies compared 724 curcumin patients and 714 controls. Using the standardized mean difference, improvement was significant with regard to pain and function in the curcumin group compared to placebo, but not with active treatment (i.e., nonsteroidal anti-inflammatory drugs, chondroitin, or paracetamol). Three studies assessed the effects of ginger on OA symptoms in 166 patients compared to 164 placebo controls. Pain was the only clinical parameter that significantly decreased. Vitamin D supplementation caused a significant decrease in pain and function. Omega-3 and vitamin E caused no changes in OA parameters. Herbal formulations effects were significant only for stiffness compared to placebo, but not with active treatment. A significant decrease in inflammatory markers was found, especially with ginger. Thus, curcumin and ginger supplementation can have a favorable impact on knee OA symptoms. Other studies are needed to better assess the effects of omega-3 and vitamin D.

The Oral Administration of Highly-Bioavailable Curcumin for One Year Has Clinical and Chondro-Protective Effects: A Randomized, Double-Blinded, Placebo-Controlled Prospective Study

Purpose

The purpose of this study was to determine the clinical and chondroprotective efficacy and safety of orally administered Theracurmin in patients who underwent mosaicplasty for knee chondral or osteochondral diseases over 12 months of treatment.

Methods

We enrolled 50 patients, older than 20 years of age, who underwent mosaicplasty for their knee joint diseases. Theracurmin at 180 mg of curcumin per day or placebo was administered orally every day for 12 months. Because 7 patients dropped out of the study, 43 patients were examined; they included 14 men and 29 women and 24 right and 19 left knees. The mean operative age was 59.5 years (range, 24-84 years). We evaluated the Japanese Orthopaedic Association knee osteoarthritis score (JOA), visual analog scale (VAS), and Japanese Knee Osteoarthritis Measure (JKOM) as clinical symptoms; T2 mapping values using magnetic resonance imaging as an indication of the chondroprotective effect; and blood concentration of curcumin at 0, 3, 6, and 12 months after the operations. We performed intraoperative acoustic evaluation of articular cartilage as a measure of chondroprotective effect during the operations and second-look arthroscopy.

Results

The JOA, VAS and JKOM at 3, 6, and 12 months were significantly better than those during the preoperative period. However, the values of JOA, VAS and JKOM and T2 mapping were not significantly different between the Theracurmin and placebo groups. The blood concentration of curcumin in the Theracurmin group was significantly higher than that in the placebo group at 3, 6, and 12 months after the operations. Cartilage stiffness and surface roughness were significantly better in the Theracurmin group than in the placebo group at second-look arthroscopy.

Conclusions

The oral administration of Theracurmin for 1 year demonstrated significantly better chondroprotective effects and no worse clinical effects and adverse events than the placebo.

Level of Evidence

Level I, double-blinded, placebo-controlled, prospective study.

The comparison of curcuminoid formulations or its combination with conventional therapies versus conventional therapies alone for knee osteoarthritis

BACKGROUND

Presently, curcuminoid formulations or its combination with conventional therapies has been used for the treatment of knee osteoarthritis (KOA). Nevertheless, evidence is limited due to small-sized clinical trials. This study aims to evaluate the efficacy of curcuminoid formulations or its combination with conventional therapies for KOA.

METHODS

Randomized controlled trials comparing curcuminoid formulations or its combination with conventional therapies versus conventional therapies, such as non-steroidal antiinflammatory drugs (NSAIDs) and chondroitin sulfate/glucosamine, were searched from databases.

RESULTS

In total, 14 studies involving 1533 patients were included. Curcuminoid formulations were comparative to NSAIDs in reducing Visual Analogue Scale (VAS), total Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, and WOMAC score for pain/stiffness/physical function. No significant difference was seen between the two groups in terms of patients' satisfaction index, patients' global assessment, reduction of several inflammatory factor, rate of drug compliance, and rescue medication. Notably, curcuminoid formulations combined with NSAIDs significantly reduced VAS and WOMAC/Knee injury and OA Outcome Score (KOOS) pain score more than NSAIDs did. In addition, the curcuminoid formulations were superior to chondroitin sulfate/glucosamine in reducing VAS, total WOMAC score, and WOMAC score for stiffness/difficulty in physical function, while no significant difference was seen in reducing WOMAC pain score and Karnofsky Performance Scale score.

CONCLUSIONS

Curcuminoid formulations may be considered a promising alternative for treating KOA. Key points • Curcuminoid formulations are comparative to NSAIDs for KOA. • Curcuminoid formulations are superior to chondroitin sulfate/glucosamine for KOA. • Curcuminoid formulations could provide additional benefits in alleviating pain and some adverse events caused by NSAIDs.

The Role of Medicinal and Aromatic Plants against Obesity and Arthritis: A Review

Obesity is a significant health concern, as it causes a massive cascade of chronic inflammations and multiple morbidities. Rheumatoid arthritis and osteoarthritis are chronic inflammatory conditions and often manifest as comorbidities of obesity. Adipose tissues serve as a reservoir of energy as well as releasing several inflammatory cytokines (including IL-6, IFN-γ, and TNF-α) that stimulate low-grade chronic inflammatory conditions such as rheumatoid arthritis, osteoarthritis, diabetes, hypertension, cardiovascular disorders, fatty liver disease, oxidative stress, and chronic kidney diseases. Dietary intake, low physical activity, unhealthy lifestyle, smoking, alcohol consumption, and genetic and environmental factors can influence obesity and arthritis. Current arthritis management using modern medicines produces various adverse reactions. Medicinal plants have been a significant part of traditional medicine, and various plants and phytochemicals have shown effectiveness against arthritis and obesity; however, scientifically, this traditional plant-based treatment option needs validation through proper clinical trials and toxicity tests. In addition, essential oils obtained from aromatic plants are being widely used as for complementary therapy (e.g., aromatherapy, smelling, spicing, and consumption with food) against arthritis and obesity; scientific evidence is necessary to support their effectiveness. This review is an attempt to understand the pathophysiological connections between obesity and arthritis, and describes treatment options derived from medicinal, spice, and aromatic plants.

Botanical Drug Extracts Combined With Biomaterial Carriers for Osteoarthritis Cartilage Degeneration Treatment: A Review of 10 Years of Research

Osteoarthritis (OA) is a long-term chronic arthrosis disease which is usually characterized by pain, swelling, joint stiffness, reduced range of motion, and other clinical manifestations and even results in disability in severe cases. The main pathological manifestation of OA is the degeneration of cartilage. However, due to the special physiological structure of the cartilage, once damaged, it is unable to repair itself, which is one of the challenges of treating OA clinically. Abundant studies have reported the application of cartilage tissue engineering in OA cartilage repair. Among them, cell combined with biological carrier implantation has unique advantages. However, cell senescence, death and dedifferentiation are some problems when cultured in vitro. Botanical drug remedies for OA have a long history in many countries in Asia. In fact, botanical drug extracts (BDEs) have great potential in anti-inflammatory, antioxidant, antiaging, and other properties, and many studies have confirmed their effects. BDEs combined with cartilage tissue engineering has attracted increasing attention in recent years. In this review, we will explain in detail how cartilage tissue engineering materials and BDEs play a role in cartilage repair, as well as the current research status.

An Investigation into the Effects of a Curcumin Extract (Curcugen®) on Osteoarthritis Pain of the Knee: A Randomised, Double-Blind, Placebo-Controlled Study

Curcumin, a phytochemical from the spice turmeric, has anti-inflammatory properties and has been shown to have pain-relieving effects. In this 8-week, randomised, double-blind, placebo-controlled study, 101 adults with knee osteoarthritis received either 500 mg twice daily of a standardised curcumin extract (Curcugen^®) or placebo. Outcome measures included the Knee Injury and Osteoarthritis Outcome Score (KOOS), knee pain ratings, Japanese Orthopaedic Association Score for Osteoarthritic Knees (JOA), PROMIS-29, and performance-based testing comprising the 40-m fast-paced walk test, 6-min walk test, timed up-and-go test, and 30-s chair stand test. Compared to the placebo, curcumin significantly reduced the KOOS knee pain score (p = 0.009) and numeric knee pain ratings (p = 0.001). Curcumin was also associated with greater improvements (p ≤ 0.05) than the placebo on the timed up-and-go test, 6-min walk test, and the JOA total score; but not the 30-s chair stand test or 40-m fast-paced walk test. Pain-relieving medication was reduced in 37% of participants on curcumin compared to 13% on placebo. The findings support the potential efficacy of curcumin for the treatment of osteoarthritis of the knee but studies of longer duration, varying treatment doses, differing curcumin extracts, and the use of other objective outcome measures will be helpful to expand on these findings.

The benefit of combining curcumin, bromelain and harpagophytum to reduce inflammation in osteoarthritic synovial cells

BACKGROUND

Osteoarthritis (OA) is the most common form of arthritis, affecting millions of people worldwide and characterised by joint pain and inflammation. It is a complex disease involving inflammatory factors and affecting the whole joint, including the synovial membrane. Since drug combination is widely used to treat chronic inflammatory diseases, a similar strategy of designing plant-derived natural products to reduce inflammation in OA joints may be of interest. In this study, we characterised the response of OA synovial cells to lipopolysaccharide (LPS) and investigated the biological action of the combination of curcumin, bromelain and harpagophytum in this original in vitro model of osteoarthritis.

METHODS

Firstly, human synovial cells from OA patients were stimulated with LPS and proteomic analysis was performed. Bioinformatics analyses were performed using Cytoscape App and SkeletalVis databases. Additionally, cells were treated with curcumin, bromelain and harpagophytum alone or with the three vegetal compounds together. The gene expression involved in inflammation, pain or catabolism was determined by RT-PCR. The release of the encoded proteins by these genes and of prostaglandin E2 (PGE2) were also assayed by ELISA.

RESULTS

Proteomic analysis demonstrated that LPS induces the expression of numerous proteins involved in the OA process in human OA synovial cells. In particular, it stimulates inflammation through the production of pro-inflammatory cytokines (Interleukin-6, IL-6), catabolism through an increase of metalloproteases (MMP-1, MMP-3, MMP-13), and the production of pain-mediating neurotrophins (Nerve Growth Factor, NGF). These increases were observed in terms of mRNA levels and protein release. LPS also increases the amount of PGE2, another inflammation and pain mediator. At the doses tested, vegetal extracts had little effect: only curcumin slightly counteracted the effects of LPS on NGF and MMP-13 mRNA, and PGE2, IL-6 and MMP-13 release. In contrast, the combination of curcumin with bromelain and harpagophytum reversed lots of effects of LPS in human OA synovial cells. It significantly reduced the gene expression and/or the release of proteins involved in catabolism (MMP-3 and -13), inflammation (IL-6) and pain (PGE2 and NGF).

CONCLUSION

We have shown that the stimulation of human OA synovial cells with LPS can induce protein changes similar to inflamed OA synovial tissues. In addition, using this model, we demonstrated that the combination of three vegetal compounds, namely curcumin, bromelain and harpagophytum, have anti-inflammatory and anti-catabolic effects in synovial cells and may thus reduce OA progression and related pain.

Current clinical developments in curcumin-based therapeutics for cancer and chronic diseases

The last decade has seen an unprecedented rise in the prevalence of chronic diseases worldwide. Different mono-targeted approaches have been devised to treat these multigenic diseases, still most of them suffer from limited success due to the off-target debilitating side effects and their inability to target multiple pathways. Hence a safe, efficacious, and multi-targeted approach is the need for the hour to circumvent these challenging chronic diseases. Curcumin, a natural compound extracted from the rhizomes of Curcuma longa, has been under intense scrutiny for its wide medicinal and biological properties. Curcumin is known to manifest antibacterial, antiinflammatory, antioxidant, antifungal, antineoplastic, antifungal, and proapoptotic effects. A plethora of literature has already established the immense promise of curcuminoids in the treatment and clinical management of various chronic diseases like cancer, cardiovascular, metabolic, neurological, inflammatory, and infectious diseases. To date, more than 230 clinical trials have opened investigations to understand the pharmacological aspects of curcumin in human systems. Still, further randomized clinical studies in different ethnic populations warrant its transition to a marketed drug. This review summarizes the results from different clinical trials of curcumin-based therapeutics in the prevention and treatment of various chronic diseases.

Effectiveness of Curcuma longa extract versus placebo for the treatment of knee osteoarthritis: A systematic review and meta-analysis of randomized controlled trials

The aim of this systematic review was to evaluate the efficacy and safety of all types of Curcuma longa extract versus placebo for knee osteoarthritis (OA) treatment. The research was conducted by using the databases of PubMed, Embase, Scopus, and Cochrane Library through April 2021. Randomized controlled trials (RCTs) that compared the effect of Curcuma longa extract with placebo for patients with knee OA were considered eligible. The pooled results were expressed as mean differences or relative risks with 95% confidence intervals. A total of 10 RCTs with 783 patients were eligible for this meta-analysis. The pooled analysis showed that Curcuma longa extract was associated with significantly better pain relief and functional improvement compared with placebo for knee OA. Moreover, the smallest effect sizes of VAS for pain and WOMAC total score exceeded the minimum clinically important differences (MCIDs). Current evidence indicates that, compared with placebo, Curcuma longa extract has more benefit in pain relief and functional improvement for symptomatic knee OA. However, considering the potential heterogeneity in the included studies, more future high-quality RCTs with large sample sizes are necessary to confirm the benefits of Curcuma longa extract on knee OA.

The efficacy and safety of Curcuma longa extract and curcumin supplements on osteoarthritis: a systematic review and meta-analysis

Objective: To assess the efficacy and safety of Curcuma longa extract and curcumin supplements on osteoarthritis (OA).

Methods: The databases such as Pubmed and Cochrane Library were searched to collect the article about Curcuma longa extract and curcumin in the treatment of OA. Then, randomized controlled trials (RCTs) were selected and their data were extracted. Finally, the RevMan5.3 was utilized for risk of bias assessment and meta-analysis, the STATA15.0 were utilized for publication bias assessment, and GRADE tool were used for the evidence quality assessment of primary outcomes.

Results: A total of 15 RCTs involving 1621 participants were included. (1) Compared with placebo, Curcuma longa extract and curcumin (C.) can decrease the visual analog scale (VAS) and The Western Ontario and McMaster Universities (WOMAC) score-pain, the WOMAC score-function and the WOMAC score-stiffness. In terms of adverse events, Curcuma longa extract and curcumin are comparable with those of placebo. (2) Compared with non-steroidal anti-inflammatory drugs (NSAIDs), Curcuma longa extract and curcumin have similar effects on joint pain, function and stiffness. The incidence of adverse events in Curcuma longa extract and curcumin was lower. (3) Compared with the NSAIDs group, C.+NSAIDs can also decrease the VAS and WOMAC score-pain, the WOMAC score-function and the WOMAC score-stiffness. In terms of adverse events, the addition of Curcuma longa extract and curcumin to NSAIDs did not increase adverse events.

Conclusion:Curcuma longa extract and curcumin may be a safer and effective supplement for OA patients. It is recommended to use Curcuma longa extract and curcumin supplement for OA patients for more than 12 weeks.

Curcumin-Alleviated Osteoarthritic Progression in Rats Fed a High-Fat Diet by Inhibiting Apoptosis and Activating Autophagy via Modulation of MicroRNA-34a

Purpose

The mechanism underlying curcumin’s protective effect on osteoarthritis (OA) has not been clarified. This study aimed to determine whether curcumin exerts a chondroprotective effect by inhibiting apoptosis via upregulation of E2F1/PITX1 and activation of autophagy via the Akt/mTOR pathway by targeting microRNA-34a (miR-34a).

Methods

Male Sprague–Dawley rats were fed a normal diet (ND) or high-fat diet (HFD) for 28 weeks. Five rats from each diet group were selected randomly for histological analysis of OA characteristics. Rats fed a HFD were given a single intra-stifle joint injection of the miR-34a mimic agomir-34a or negative control agomir (NC), followed by weekly low-dose (200 μg/kg body weight) or high-dose (400 μg/kg body weight) curcumin intra-joint injections from weeks 29 to 32. The rats’ stifle joints were submitted to histological analysis and to an apoptotic assay. Expression of miR-34a was detected using a real-time RT-PCR. E2F1 and PITX1 protein levels were determined by Western blot analysis, and the expressions of Beclin1, LC3B, p62, phosphorylated (p)-Akt, and p-mTOR were measured using immunofluorescence analysis.

Results

We found that rats fed a HFD had OA-like lesions in their articular cartilage and had increased apoptosis of chondrocytes and decreased autophagy compared to rats fed a ND. Curcumin treatment alleviated OA changes, inhibited apoptosis, and upregulated autophagy. Agomir-34a treatment reduced E2F1, PITX1, Beclin1, and LC3B expression and increased p62, p-Akt, and p-mTOR expression in HFD-fed rats given low- or high-dose curcumin. Greater numbers of apoptotic cells, lesser expression of p62, p-Akt, and p-mTOR, and greater expression of E2F1, PITX1, and LC3B were observed in the agomir-34a and high-dose curcumin-treated group than in agomir-34a and low-dose curcumin-treated group.

Conclusion

Curcumin’s chondroprotective effect was mediated by its suppression of miR-34a, apparently by reducing apoptosis, via upregulation of E2F1/PITX1, and by augmenting autophagy, likely via the Akt/mTOR pathway.

Curcuminoids and Boswellia serrata extracts combination decreases tendinopathy symptoms: findings from an open-label post-observational study

Background: To investigate the effects of 1-month treatment in addition to standard care with a food supplement containing both Curcuma longa and Boswellia serrata extracts on tendinopathy symptoms.Method: This open-label, non-controlled, post-observational study included 670 patients suffering from tendinopathy recruited at different sites by Belgian general practitioners. Patients received a medical prescription for 1-month treatment with two tablets twice a day of a pharmaceutical grade food supplement containing both C. longa and B. serrata extracts. Pain and functional limitation were evaluated using a visual analog scale at the inclusion and 1-month treatment later. Patient satisfaction, concomitant drugs intake and side effects were also recorded.Results: After 1-month treatment, pain and functional limitation were significantly improved whatever the cause of tendinopathy, its localization, and the duration of symptoms. The pain score decreased from 6.16 ± 1.53 to 2.98 ± 1.64 (p < .0001), yielding a drop of 51.6% and the functional limitation score fell after 1-month treatment from 5.96 ± 1.73 to 2.88 ± 1.67 (p < .0001) corresponding to a drop of 51.6%. The percentage of patients taking at least one concomitant treatment at the end of the treatment period had decreased from 81.3% to 61.8% (p < .0001). Only 43 (6.5%) patients reported side effects. No severe adverse effects related to the product were reported.Conclusion: The combination of C. longa and B. serrata extracts improves symptoms in patients suffering of tendinopathy and shows a good safety. Although its effect will have to be confirmed in randomized controlled trials, it can be considered as a helpful support of standard symptomatic treatments for tendinopathies. HighlightsTendinopathy is a common disease representing 30% of all consultations with a general practitioner for musculoskeletal disorders.The combination of Curcuminoids and Boswelliaserrata extracts are efficient on tendinopathy symptoms in support of standard symptomatic treatments.The combination of Curcuminoids and B. Serrata extract is safe and can be administrated for at least 1 month in addition of analgesic and non-steroidal anti-inflammatory drugs.

Therapeutic effects of turmeric or curcumin extract on pain and function for individuals with knee osteoarthritis: a systematic review

Purpose

To determine whether supplementation with turmeric or curcumin extract effects pain and physical function in individuals with knee osteoarthritis (OA). Second, we investigated the therapeutic response (pain and function) of turmeric compared with non-steroidal anti-inflammatory drugs (NSAIDs).

Methods

A search was conducted in MEDLINE, Embase, CINAHL and Cochrane Review. Inclusion criteria included randomised controlled trials reporting pain and physical function in humans with knee OA comparing turmeric therapy with NSAIDs or no therapy. Two reviewers screened 5273 abstracts. Risk of bias and quality were assessed via Cochrane Collaboration tool and CONSORT (Consolidated Standards of Reporting Trials) 2010, respectively.

Results

Ten studies were included in the final analysis. Eight had high methodological quality and two were categorised as good with a mean CONSORT quality score of 21.1. Nine studies had adequate sequence generation and six had adequate allocation concealment. Participants and outcome assessors were blinded in eight studies. Three of the studies compared turmeric therapy to NSAIDs. All 10 studies showed improvement in pain and function from baseline with turmeric therapy (p≤0.05). In three studies comparing turmeric to NSAIDs, there were no differences in outcome scores (p>0.05). In all studies there were no significant adverse events in the turmeric therapy group.

Conclusion

Compared with placebo, there appears to be a benefit of turmeric on knee OA pain and function. Based on a small number of studies the effects are similar to that of NSAIDs. Variables such as optimal dosing, frequency and formulation remain unclear at this time.

Clusters of Responders and Predictive Factors for Response to Supplementation with Boswellia, Turmeric, and Red Algae Extracts in Painful Knee Osteoarthritis: A Prospective Observational Study Using an Arsenal of Patient-Centered Measures

Purpose

This observational study evaluated a combination of boswellia, turmeric, and red algae extracts in patients with knee osteoarthritis (KOA). Given the growing interest in patient-centered care in osteoarthritis, effects were assessed by an arsenal of patient-reported outcome measures (PROMs): Patient Acceptable Symptom Scale (PASS), Minimal Clinically Important Improvement (MCII), Patient Global Impression of Change (PGIC), and Lequesne algofunctional index (LAFI). Patients also completed a list of 17 items on pain quality.

Patients and Methods

Patients with painful unilateral or bilateral KOA had to take 1-4 capsules per day of a dietary supplement containing boswellia, turmeric, and red algae extracts for 90 days. Patients completed PROMs on Days 0 (baseline), 10, 20, 30, 60, and/or 90.

Results

A total of 118 patients [female: 69.5%; age: 62.9 (9.5) years, mean (SD)] were included in the study and took at least one capsule. Mean (SD) follow-up duration was 100.7 (54.9) days. Pain relief was maximal on Day 90: 64.5% of patients were responders (positive PASS); 68.8% and 58.4% had MCII and PGIC scores indicating positive effect (score ≥3) or global improvement (score ≥5); 73.3% (versus 47.5% at baseline) were mildly/moderately disabled (LAFI score <8); 55.2% had meaningful decrease (-30%) in pain intensity (VAS), 35.1% (versus 59.2% at baseline) took analgesics as supplementary treatment. Median time to the first PASS change was 34 days. Pain intensity (VAS), as well as two pain characteristics (ie, "Stabbing pain" and "Widespread pain"), were independent factors associated with non-response on Day 30. Four clusters of responders were isolated according to pain characteristics, with one cluster exhibiting a higher responder rate.

Conclusion

The results of this preliminary study suggest that the combination of boswellia, turmeric, and red algae extracts tested could improve KOA patients. Beyond these results, this study showed the importance of PROMs and specific pain qualitative descriptors for the accurate evaluation of dietary supplement approaches in painful conditions.

A Systematic Review of the Clinical Use of Curcumin for the Treatment of Osteoarthritis

Osteoarthritis is characterized by degeneration of joint structure over time, resulting in limitation of joint mobility. There is growing evidence that curcumin has anti-inflammatory properties and could be a potential therapeutic option for chronic inflammatory diseases. Hence, curcumin could potentially have a positive impact on osteoarthritis symptoms. This systematic review aimed to estimate the effects of curcumin on osteoarthritis. We systematically searched PubMed, ISI, Scopus, and Google Scholar up to March 4, 2020 to identify randomized controlled trials that evaluated the effects of consumption of all types of curcumin compounds in the treatment of osteoarthritis, especially in patients with knee osteoarthritis. Seventeen trials were identified. The duration of the included studies varied from 4 weeks to 8 months. Across all trials, 13 studies involved screening using Western Ontario and McMaster Universities (WOMAC) scores and 11 studies used visual analog scales (VAS) for recording pain from baseline to post-intervention. There was a significant improvement in VAS and overall WOMAC scores with oral administration of various types of curcumin formulations with no severe adverse effects. In conclusion, different types of curcumin compounds may be beneficial as an alternative or complementary agent for the management of osteoarthritis. Moreover, certain curcumin compounds with higher bioavailability tended to show more positive effects.

Improved Joint Mobility Associated with Reduced Inflammation Related to Consumption of Nopal Cactus Fruit Juice: Results from a Placebo-Controlled Trial Using Digital Inclinometry to Objectively Document Mobility of All Major Joints

Objective

To evaluate the effects of daily consumption of Nopal cactus fruit juice (NFJ) on joint mobility in a population experiencing chronic pain but otherwise in good health.

Study Design

A double-blind, placebo-controlled study design was used to enroll 40 people after written informed consent, randomized to consume 3 oz/day of NFJ versus placebo. At baseline and 8 weeks, joint range of motion (ROM) was examined by digital inclinometry along the vertical weight-bearing axis of the body from neck to knees and the shoulders. Blood samples were tested for cytokines and C-reactive protein (CRP). Questionnaires addressed wellness, pain, and reliance on pain medications.

Results

After 8 weeks of consuming NFJ, participants showed improved ROM beyond that of participants consuming placebo. Cervical and thoracic/lumbar ROM for the NFJ group was significantly improved when compared to placebo (cervical: P<0.03, thoracic/lumbar: P<0.04). People consuming NFJ relied less on pain medication to complete daily activities (P<0.1) and experienced reduced interference from pain and breathing issues (not significant). Serum levels of Eotaxin, involved in airway inflammation, showed significant differences between placebo and NFJ groups after 8 weeks (P<0.048). Changes in CRP levels showed a larger reduction in the NFJ group (-13%) than in the placebo group (-4%) (not significant). In the subgroup with CRP levels between 1 and 9.9 mg/L at baseline, CRP levels decreased in the NFJ group (-30%) but increased in the placebo group (31%) (P<0.015).

Conclusion

Consumption of NFJ for 8 weeks was associated with statistically significant improvements in joint mobility and physical functioning compared to the placebo group, allowing participants in the NFJ group to be more physically active; daily activities were easier, including walking, sitting, and lying. This was associated with reduced use of pain medication, possibly associated with anti-inflammatory properties of NFJ, as suggested by reduced Eotaxin and CRP levels.

Effectiveness of Curcuma longa Extract for the Treatment of Symptoms and Effusion-Synovitis of Knee Osteoarthritis : A Randomized Trial

BACKGROUND

Current pharmacologic therapies for patients with osteoarthritis are suboptimal.

OBJECTIVE

To determine the efficacy of Curcuma longa extract (CL) for reducing knee symptoms and effusion-synovitis in patients with symptomatic knee osteoarthritis and knee effusion-synovitis.

DESIGN

Randomized, double-blind, placebo-controlled trial. (Australian New Zealand Clinical Trials Registry: ACTRN12618000080224).

SETTING

Single-center study with patients from southern Tasmania, Australia.

PARTICIPANTS

70 participants with symptomatic knee osteoarthritis and ultrasonography-defined effusion-synovitis.

INTERVENTION

2 capsules of CL (n = 36) or matched placebo (n = 34) per day for 12 weeks.

MEASUREMENTS

The 2 primary outcomes were changes in knee pain on a visual analogue scale (VAS) and effusion-synovitis volume on magnetic resonance imaging (MRI). The key secondary outcomes were change in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and cartilage composition values. Outcomes were assessed over 12 weeks.

RESULTS

CL improved VAS pain compared with placebo by -9.1 mm (95% CI, -17.8 to -0.4 mm [P = 0.039]) but did not change effusion-synovitis volume (3.2 mL [CI, -0.3 to 6.8 mL]). CL also improved WOMAC knee pain (-47.2 mm [CI, -81.2 to -13.2 mm]; P = 0.006) but not lateral femoral cartilage T2 relaxation time (-0.4 ms [CI, -1.1 to 0.3 ms]). The incidence of adverse events was similar in the CL (n = 14 [39%]) and placebo (n = 18 [53%]) groups (P = 0.16); 2 events in the CL group and 5 in the placebo group may have been treatment related.

LIMITATION

Modest sample size and short duration.

CONCLUSION

CL was more effective than placebo for knee pain but did not affect knee effusion-synovitis or cartilage composition. Multicenter trials with larger sample sizes are needed to assess the clinical significance of these findings.

PRIMARY FUNDING SOURCE

University of Tasmania and Natural Remedies Private Limited.

Curcumin, autoimmune and inflammatory diseases: going beyond conventional therapy - a systematic review

Autoimmune and inflammatory diseases affect innumerous people and are considered a significant cause of morbidity and mortality worldwide and Curcuma sp can work as important therapies in the approach of these diseases. For this reason the aim of this review is to evaluate the effects of Curcuma or curcumin in five autoimmune and/or inflammatory diseases for instance, Inflammatory Bowel Disease, Osteoarthritis, Systemic Lupus Erythematous, Psoriasis, and Sclerosis. MEDLINE, EMBASE, and Cochrane Library were searched and PRISMA guidelines were used to build this systematic review. Curcuma sp or curcumin have been gaining ground in the treatment of autoimmune and inflammatory diseases due to the wide range of bioactive compounds capable of exerting substantial anti-inflammatory and antioxidant actions. The effects can be associated with improvement of symptoms and induction of remission in Inflammatory Bowel Disease patients; reduction of erythema and induration of lesions in psoriasis; and slow down the disease progression in patients with sclerosis. Furthermore, curcumin shows effects equivalent to ibuprofen and diclofenac, without the adverse effects generally reported by patients. Curcuma or its derivatives can be used safely and efficiently as adjuvants or as a main therapy for these diseases that increase year by year in the world population.

Future of Chondroprotectors in the Treatment of Degenerative Processes of Connective Tissue

Osteoarthritis is one of the most common diseases of the connective tissue of the elderly. It was found that most epidemiological studies used the Kellgren and Lawrence system for classification of osteoarthritis, which indicates one of the 5 degrees (0-4) of osteoarthritis in various joints according to the radiographic atlas. It has been proven that chondroprotectors are represented by the following active substances: chondroitin sulfate, glucosamine sulfate or hydrochloride, hyaluronic acid, glycosaminoglycans, extraction preparations from animal or plant raw materials. The sources of raw materials for the manufacture of combined chondroprotectors are known, methods for their preparation and use are described. The main drugs on the chondroprotective market are presented. The effectiveness of their use for the treatment of osteoarthritis has been proven. It was found that preparations containing chondroitin sulfate have anti-inflammatory activity, affecting mainly the cellular component of inflammation, stimulate the synthesis of hyaluronic acid and proteoglycans. Methods of treating osteoarthritis using cell therapy (the use of readily available, highly proliferative, and multipotent mesenchymal stromal cells) are presented.

Medicinal plants used against various inflammatory biomarkers for the management of rheumatoid arthritis

OBJECTIVES

Rheumatoid arthritis is a chronic autoimmune disease manifested clinically by polyarthralgia associated with joint dysfunction triggering the antibodies targeting against the self-neoepitopes determined by autoimmune responses associated with chronic arthritic attacks. The activation of macrophages and other defence cells in response to self-epitopes as biomarkers in RA provides a better understanding of pathogenesis of disease and has led to the development of novel therapeutic approaches acting as potent inhibitors of these cells.

KEY FINDINGS

The current review retrieved the various medicinal plants possessing an active phytoconstituents with anti-inflammatory and antioxidant properties, which tends to be effective alternative approach over the synthetic drugs concerned with high toxic effects. The current available literature provided an evident data concluding that the active constituents like fatty acids, flavonoids, terpenes and sesquiterpene lactones attenuate the RA symptoms by targeting the inflammatory biomarkers involved in the pathogenesis of RA.

SUMMARY

Despite the various synthetic treatment approaches targeting immune cells, cytokines improved the quality of life but still the drug management is challenging due to toxic and chronic teratogenic effects with anti-arthritic drugs. The current review has elaborated the selected traditionally used herbal medicinal plants with phytoconstituents possessing anti-inflammatory activity by suppressing the inflammatory biomarkers with lesser side effects and providing the future exploration of natural drug therapy for rheumatoid arthritis.

What is the selection process for osteoarthritis pharmacotherapy?

Osteoarthritis is the most prevalent joint condition that continues to increase with an ever-aging population and the rising tide of obesity. There are multiple recommendations/guidelines for the management of osteoarthritis. The basis of management should focus on self-management and education, lifestyle modifications, exercise and when appropriate, weight loss. Pharmacotherapy is targeted toward pain palliation with no agents available presently to target prevention and disease modification. The selection of pharmacotherapy should be tailored to the individual, taking into account of personal preferences and interactions with underlying co-morbidities. This editorial provides a guide to the selection process of presently available pharmacotherapy in osteoarthritis.

Alternative and complementary therapies in osteoarthritis and cartilage repair

Osteoarthritis (OA) is the most common joint condition and, with a burgeoning ageing population, is due to increase in prevalence. Beyond conventional medical and surgical interventions, there are an increasing number of ‘alternative’ therapies. These alternative therapies may have a limited evidence base and, for this reason, are often only afforded brief reference (or completely excluded) from current OA guidelines. Thus, the aim of this review was to synthesize the current evidence regarding autologous chondrocyte implantation (ACI), mesenchymal stem cell (MSC) therapy, platelet-rich plasma (PRP), vitamin D and other alternative therapies. The majority of studies were in knee OA or chondral defects. Matrix-assisted ACI has demonstrated exceedingly limited, symptomatic improvements in the treatment of cartilage defects of the knee and is not supported for the treatment of knee OA. There is some evidence to suggest symptomatic improvement with MSC injection in knee OA, with the suggestion of minimal structural improvement demonstrated on MRI and there are positive signals that PRP may also lead to symptomatic improvement, though variation in preparation makes inter-study comparison difficult. There is variability in findings with vitamin D supplementation in OA, and the only recommendation which can be made, at this time, is for replacement when vitamin D is deplete. Other alternative therapies reviewed have some evidence (though from small, poor-quality studies) to support improvement in symptoms and again there is often a wide variation in dosage and regimens. For all these therapeutic modalities, although controlled studies have been undertaken to evaluate effectiveness in OA, these have often been of small size, limited statistical power, uncertain blindness and using various methodologies. These deficiencies must leave the question as to whether they have been validated as effective therapies in OA (or chondral defects). The conclusions of this review are that all alternative interventions definitely require clinical trials with robust methodology, to assess their efficacy and safety in the treatment of OA beyond contextual and placebo effects.

Enhancement of chemical stability of curcumin-enriched oil-in-water emulsions: Impact of antioxidant type and concentration

Curcumin is claimed to have many health benefits, but it has low chemical stability. In this study, the influence of food-grade antioxidants on the chemical degradation of curcumin-enriched oil-in-water emulsions was examined. The curcumin degradation rate and extent depended on antioxidant type. The water-soluble antioxidants were more effective at protecting curcumin from degradation than the oil-soluble ones, which may have been because curcumin degrades faster in water than in oil. Interestingly, the amphiphilic antioxidant was almost as effective as the water-soluble ones. The oil-soluble antioxidant actually slightly promoted curcumin degradation. In summary, curcumin retention after storage declined in the following order: 82.6% (Trolox) ~82.2% (ascorbic acid) >79.5% (ascorbyl palmitate) ≫57.9% (control) >52.7% (α-tocopherol). The effectiveness of ascorbic acid in stabilizing curcumin increased as its concentration was raised (0-300 μM). Our results may facilitate the creation of curcumin-enriched foods and beverages with enhanced bioactivity.