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

Exploring the Potential of Dietary Supplements to Alleviate Pain Due to Long COVID

Long COVID, characterized by persistent symptoms following COVID-19 infection, significantly impacts individuals' health and daily functioning due to fatigue and pain. Focusing on pain, this review addresses nociplastic and chronic pain conditions. Interventions designed to reduce inflammation, oxidative stress, and enhance vagal activity may offer a promising approach to managing post-pandemic pain. This review presents individual components of food supplements with demonstrated efficacy in one or more pain conditions, focusing on their proposed mechanisms and clinical activity in pain, including their use in post-COVID-19 pain when available. Many of these substances have a long history of safe use and may offer an alternative to long-term analgesic drug treatment, which is often associated with potential side effects. This review also explores the potential for synergistic effects when combining these substances with each other or with conventional analgesics, considering the advantages for both patients and the healthcare system in using these substances as adjunctive or primary therapies for pain symptoms related to long COVID. While preclinical scientific literature provides a mechanistic basis for the action of several food supplements on pain control mechanisms and signaling pathways, clinical experience, particularly in the field of long COVID-associated pain, is still limited. However, the reviewed literature strongly suggests that the use of food supplements in long COVID-associated pain is an attainable goal, provided that rigorous clinical trials are conducted.

Application of curcuminoids in inflammatory, neurodegenerative and aging conditions - Pharmacological potential and bioengineering approaches to improve efficiency

Curcumin, a natural compound found in turmeric, has shown promise in treating brain-related diseases and conditions associated with aging. Curcumin has shown multiple anti-inflammatory and brain-protective effects, but its clinical use is limited by challenges like poor absorption, specificity and delivery to the right tissues. A range of contemporary approaches at the intersection with bioengineering and systems biology are being explored to address these challenges. Data from preclinical and human studies highlight various neuroprotective actions of curcumin, including the inhibition of neuroinflammation, modulation of critical cellular signaling pathways, promotion of neurogenesis, and regulation of dopamine levels. However, curcumin's multifaceted effects - such as its impact on microRNAs and senescence markers - suggest novel therapeutic targets in neurodegeneration. Tetrahydrocurcumin, a primary metabolite of curcumin, also shows potential due to its presence in circulation and its anti-inflammatory properties, although further research is needed to elucidate its neuroprotective mechanisms. Recent advancements in delivery systems, particularly brain-targeting nanocarriers like polymersomes, micelles, and liposomes, have shown promise in enhancing curcumin's bioavailability and therapeutic efficacy in animal models. Furthermore, the exploration of drug-laden scaffolds and dermal delivery may extend the pharmacological applications of curcumin. Studies reviewed here indicate that engineered dermal formulations and devices could serve as viable alternatives for neuroprotective treatments and to manage skin or musculoskeletal inflammation. This work highlights the need for carefully designed, long-term studies to better understand how curcumin and its bioactive metabolites work, their safety, and their effectiveness.

Efficacy and Safety of a Novel Low-Dose Water-Dispersible Turmeric Extract in the Management of Knee Osteoarthritis: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Purpose

Turmeric extract is a well-known nutraceutical ingredient recognized for its benefits in managing musculoskeletal health. This study evaluated the efficacy and safety of a novel low-dose water-dispersible turmeric extract containing 60% natural curcuminoids (WDTE60N) in participants with mild-to-moderate knee osteoarthritis.

Patients and Methods

This double-blind, randomized, placebo-controlled trial was conducted at two orthopedic centers in Uttar Pradesh, India (July 2023-November 2023). Participants aged 45-75 years with unilateral or bilateral OA of the knee for >3 months were randomized in 1:1 ratio to receive WDTE60N (250 mg) or placebo capsules once daily for three months. Study endpoints included assessment of changes from baseline to day 90 in pain intensity (visual analog scale [VAS], knee injury and osteoarthritis outcome score [KOOS]), inflammatory biomarkers, and safety profile. Data were analyzed using independent t-test, chi-square test, and analysis of co-variance test.

Results

In total, 139 participants (WDTE60N, n = 70; placebo, n = 69) with mean age and BMI of 56.35 years and 23.89 kg/m2, respectively, were included. The mean reduction (95% CI) in VAS score from baseline to day 90 was significantly higher in the WDTE60N group than in the placebo group (14.41 [13.08, 15.75] vs 6.02 [5.00, 7.05]; p < 0.0001). In the WDTE60N group, the mean change in VAS scores was significantly reduced from as early as day 07 (p = 0.0076), which continued until day 90 (p < 0.0001), compared to the placebo group. Improvement in the mean KOOS scores (baseline-Day 90) was evident, with significantly higher mean scores for each domain (pain, symptoms, activities of daily living, function in sport and recreation, and knee-related quality of life [QoL]) on Day 90 in the WDTE60N group than in the placebo group (p < 0.05). Inflammatory biomarkers (hsCRP, TNF-α, IL-6, and IL-1β) were significantly reduced from baseline to day 90 in the WDTE60N group compared to the placebo group (p < 0.0001). Four mild adverse events were reported during the study period.

Conclusion

Supplementation with the low-dose water-dispersible turmeric extract containing 60% natural curcuminoids for three months was safe and effective in alleviating pain, improving functional status and quality of life and reducing inflammation in participants with mild-to-moderate knee osteoarthritis.

CTRI Registration Number

CTRI/2023/07/055411.

Identification of biomarkers for knee osteoarthritis through clinical data and machine learning models

Knee osteoarthritis (KOA) represents a progressive degenerative disorder characterized by the gradual erosion of articular cartilage. This study aimed to develop and validate biomarker-based predictive models for KOA diagnosis using machine learning techniques. Clinical data from 2594 samples were obtained and stratified into training and validation datasets in a 7:3 ratio. Key clinical features were identified through differential analysis between KOA and control groups, combined with least absolute shrinkage and selection operator (LASSO) regression. The SHapley Additive Planning (SHAP) method was employed to rank feature importance quantitatively. Based on these rankings, predictive models were constructed using Logistic Regression (LR), Random Forest (RF), eXtreme Gradient Boosting (xGBoost), Naive Bayes (NB), Support Vector Machine (SVM), and Decision Tree (DT) algorithms. Models were developed for subsets of variables, including the top 5, top 10, top 15, and all identified features. Receiver operating characteristic (ROC) curves were applied to compare diagnostic performance across models. Additionally, a risk stratification framework for KOA prediction was designed using recursive partitioning analysis (RPA). Using difference analysis and LASSO, 44 critical clinical features were identified. Among these, age, plasma prothrombin time, gender, body mass index (BMI), and prothrombin time and international normalized ratio (PTINR) emerged as the top five features, with SHAP values of 0.1990, 0.0981, 0.0471, 0.0433, and 0.0422, respectively. Machine learning analysis demonstrated that these variables provided robust diagnostic performance for KOA. In the training set, area under the curve (AUC) values for LR, RF, xGBoost, NB, SVM, and DT models were 0.947, 0.961, 0.892, 0.952, 0.885, and 0.779, respectively. Similarly, in the validation dataset, these models achieved AUC values of 0.961, 0.943, 0.789, 0.957, 0.824, and 0.76. Among them, RF consistently exhibited superior diagnostic accuracy for KOA. Additionally, RPA analysis indicated a higher prevalence of KOA among individuals aged 54 years and older. The integration of the top five clinical variables significantly enhanced the diagnostic accuracy for KOA, particularly when employing the RF model. Moreover, the RPA model offered valuable insights to assist clinicians in refining prognostic assessments and optimizing clinical decision-making processes.

Efficacy of Curcuma longa in relieving pain symptoms of knee osteoarthritis patients: a systematic review and meta-analysis of clinical trials

Objective

Osteoarthritis (OA), particularly knee OA, affects 24% of adults and is a significant cause of disability. Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used but have many adverse effects. Antioxidant and anti-iflammatory properties of Curcuma longa might decrease pain thus improving joint function.

Methods

This systematic review and meta-analysis evaluated randomized controlled trials (RCTs) on Curcuma longa efficacy for knee OA. We reported mean differences (MD) with 95% confidence interval (CI) for continuous outcomes and evaluated Visual Analog Scale (VAS) for pain and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) total score over 4 to 6 weeks for treatment effects.

Results

Ten RCTs with 786 patients were included. Curcuma longa significantly improved VAS for pain than placebo (MD 18.25, 95% CI 7.79 to 28.72, p=0.0006). It was not inferior to NSAIDs in WOMAC total score improvement (MD -11.99, 95% CI -39.21 to 15.23, p=0.39). Both dosages (<1,000 and ≥1,000 mg/day) of Curcuma longa demonstrated similar improvement in VAS for pain compared to placebo (MD 27.02, 95% CI 1.45 to 52.60, p=0.04; MD 21.48, 95% CI 1.78 to 41.18, p=0.03).

Conclusion

Curcuma longa benefits knee OA pain and function, being more effective than placebo and comparable to NSAIDs. Despite positive results, limitation and heterogeneity of the studies necessitates further research to explore optimal dosages and administration methods of Curcuma longa as therapeutic option for knee OA.

Review perspective on advanced nutrachemicals and anterior cruciate ligament rehabilitation

Anterior cruciate ligament (ACL) injuries are prevalent among athletes, necessitating surgical intervention followed by comprehensive rehabilitation. Recently, the integration of nutraceuticals - bioactive compounds from food sources - into rehabilitation protocols has shown promise in enhancing recovery outcomes. This review explores the potential benefits of various nutraceuticals, including omega-3 fatty acids, collagen supplements, vitamin D, glucosamine and chondroitin, curcumin, and branched-chain amino acids (BCAAs), in ACL rehabilitation. These nutraceuticals offer anti-inflammatory properties, support tissue repair, and improve joint and muscle health, which are critical during the rehabilitation process. Despite encouraging preclinical findings, there is a need for robust clinical trials to confirm their efficacy and establish optimal dosages and formulations. Personalized nutrition plans and interdisciplinary collaboration among healthcare providers are essential for optimizing patient care. This perspective underscores the potential of advanced nutraceuticals to revolutionize ACL rehabilitation, paving the way for faster and more effective recovery pathways.

Impact of Drying Methods on Phenolic Composition and Bioactivity of Celery, Parsley, and Turmeric-Chemometric Approach

Drying is one of the most commonly used methods for food preservation, and in spice processing, it has a significant impact on quality. In this paper, the influences of drying at room temperature, 60 °C, and 90 °C and freeze-drying on celery and parsley roots and turmeric rhizomes were examined. The highest content of total phenolics was found in celery dried at 60 °C (C60), parsley at room temperature (PRT), and freeze-dried turmeric (TFD) (1.44, 1.58, and 44.92 mg GAE/gdm, respectively). Celery dried at room temperature (CRT), PRT, and TFD showed the highest antioxidant activity regarding the DPPH and ABTS radicals and FRAP. The analysis of color parameters revealed that celery dried at 90 °C (C90); PFD and TFD showed the most similar values to control samples. The drying process was optimized using a combination of standard score (SS) and artificial neural network (ANN) methods. The ANN model effectively evaluated the significance of drying parameters, demonstrating high predictive accuracy for total phenolics, total flavonoids, total flavonols, total flavan-3-ols, IC50ABTS, and FRAP. TFD showed the strongest α-glucosidase inhibitory potential. Also, TFD extract showed good antibacterial activity against Staphylococcus aureus but not against Escherichia coli. C90 and PFD extracts did not show antibacterial activity against the tested microorganisms.

Bioactive Compounds and Their Chondroprotective Effects for Osteoarthritis Amelioration: A Focus on Nanotherapeutic Strategies, Epigenetic Modifications, and Gut Microbiota

In degenerative joint disease like osteoarthritis (OA), bioactive compounds like resveratrol, epigallocatechin gallate, curcumin, and other polyphenols often target various signalling pathways, including NFκB, TGFβ, and Wnt/β-catenin by executing epigenetic-modifying activities. Epigenetic modulation can target genes of disease pathophysiology via histone modification, promoter DNA methylation, and non-coding RNA expression, some of which are directly involved in OA but have been less explored. OA patients often seek options that can improve the quality of their life in addition to existing treatment with nonsteroidal anti-inflammatory drugs (NSAIDs). Although bioactive and natural compounds exhibit therapeutic potential against OA, several disadvantages loom, like insolubility and poor bioavailability. Nanoformulated bioactive compounds promise a better way to alleviate OA since they also control systemic events, including metabolic, immunological, and inflammatory responses, by modulating host gut microbiota that can regulate OA pathogenesis. Recent data suggest gut dysbiosis in OA. However, limited evidence is available on the role of bioactive compounds as epigenetic and gut modulators in ameliorating OA. Moreover, it is not known whether the effects of polyphenolic bioactive compounds on gut microbial response are mediated by epigenetic modulatory activities in OA. This narrative review highlights the nanotherapeutic strategies utilizing bioactive compounds, reporting their effects on chondrocyte growth, metabolism, and epigenetic modifications in osteoarthritis amelioration.

Curcumin regulates autophagy through SIRT3-SOD2-ROS signaling pathway to improve quadriceps femoris muscle atrophy in KOA rat model

Knee osteoarthritis (KOA) usually leads to quadriceps femoris atrophy, which in turn can further aggravate the progression of KOA. Curcumin (CUR) has anti-inflammatory and antioxidant effects and has been shown to be a protective agent for skeletal muscle. CUR has been shown to have a protective effect on skeletal muscle. However, there are no studies related to whether CUR improves KOA-induced quadriceps femoris muscle atrophy. We established a model of KOA in rats. Rats in the experimental group were fed CUR for 5 weeks. Changes in autophagy levels, reactive oxygen species (ROS) levels, and changes in the expression of the Sirutin3 (SIRT3)-superoxide dismutase 2 (SOD2) pathway were detected in the quadriceps femoris muscle of rats. KOA led to quadriceps femoris muscle atrophy, in which autophagy was induced and ROS levels were increased. CUR increased SIRT3 expression, decreased SOD2 acetylation and ROS levels, inhibited the over-activation of autophagy, thereby alleviating quadriceps femoris muscle atrophy and improving KOA. CUR has a protective effect against quadriceps femoris muscle atrophy, and KOA is alleviated after improvement of quadriceps femoris muscle atrophy, with the possible mechanism being the reduction of ROS-induced autophagy via the SIRT3-SOD2 pathway.