A putative Chondroprotective role for IL-1β and MPO in herbal treatment of experimental osteoarthritis

Non-Animal Hyaluronic Acid and Probiotics Enhance Skin Health via the Gut-Skin Axis: An In Vitro Study on Bioavailability and Cellular Impact

Hyaluronic acid (HA) represents a pivotal component of the extracellular matrix, particularly within the context of the skin. The absorption and metabolism of orally ingested HA have been extensively investigated due to the prevalence of HA-based supplements. The objective of this study was to evaluate the impact of a combination of non-animal HA and Bifidobacterium longum novaBLG1 on dermal health following intestinal transit. The bioavailability of the compound was evaluated using a model that reproduced the human intestinal barrier in vitro, and its biological effects were investigated on skin cells via the gut-skin axis. The results demonstrated that probiotics augmented the absorption of non-animal HA by approximately 30% in comparison to non-animal HA alone and by 82% in comparison to sodium hyaluronate. Furthermore, the combination demonstrated a notable enhancement in skin cell proliferation, with increases of 16%, 8%, and 29.7% over 144 h in comparison to non-animal hyaluronan, Bifidobacterium longum novaBLG1, and sodium hyaluronate, respectively. The combination was observed to positively affect all markers of skin health and well-being, achieving its goals without any adverse effects on the gut. This approach offers a novel method for enhancing skin health.

Aromatic Plants as Potential Resources to Combat Osteoarthritis

Osteoarthritis, which affects an estimated 10% of men and 18% of women over the age of 60 and is increasing in genetic prevalence and incidence, is acknowledged as the condition that degrades the quality of life for older adults in the world. There is currently no known treatment for osteoarthritis. The majority of therapeutic methods slow the progression of arthritis or treat its symptoms, making effective treatment to end the degenerative process of arthritis elusive. When non-pharmacological therapy is ineffective, various pharmacological therapies may be used to treat osteoarthritis. Pharmacological therapy, however, can have major adverse effects and be very expensive. As a result, alternative remedies have been researched. The promise for the safe and efficient management of osteoarthritis has been demonstrated by herbal remedies. Experimental research suggests that herbal extracts and compounds can reduce inflammation, inhibit catabolic processes, and promote anabolic processes that are important for treating osteoarthritis. Due to their therapeutic and innate pharmacological qualities, aromatic herbs are frequently employed as herbal remedies. Recent research has shown that aromatic plants have the potency to treat osteoarthritis. Additionally, complex mixtures of essential oils and their bioactive ingredients, which have anti-inflammatory and antioxidant properties and are obtained from aromatic plants, are frequently utilized as complementary therapies for osteoarthritis. To establish new study avenues, the advantageous anti-osteoarthritic effects of aromatic herbal medicines, including plants, essential oils, and their bioactive components, are extensively discussed.

Formulation of a dual drug-loaded nanoparticulate co-delivery hydrogel system and its validation in rheumatoid arthritis animal model

Rheumatoid arthritis (RA), a systemic autoimmune disease that dramatically affects patients' quality of life. Given the intricacy of RA's pathophysiology, no single treatment can completely halt the disease progression. Here, we attempted to treat RA holistically and synergistically by co-delivering methotrexate (MTX), a standard slow-acting anti-rheumatic drug, and phenethyl isothiocyanate (PEITC), a bioactive phytochemical, using a sodium alginate (SA)-pluronic F127 (PF-127) in situ hydrogel formulation. Therefore, in the current study, the co-delivery of MTX and PEITC in the nanoparticulate form could help enhance stability and solubility and facilitate greater penetration in the target arthritic tissues. The fabricated MTX NP and PEITC NE were found to have a minimum particle size, PDI, and good zeta potential. Results from in vitro release studies showed that MTX and PEITC were simultaneously released from the DD NP HG matrix over 6-7 days through diffusion and erosion mechanisms. An intra-articular (IA) injection of DD NP HG dramatically reduced chronic inflammation in adjuvant-induced arthritis (AIA) rats, delayed the onset of bone erosion, significantly reduced synovitis, and down-regulated the inflammatory cytokine expression. Most notably, the co-delivery strategy almost entirely restored the morphological features of the ankle joints of RA rats. The hepatic and renal function tests indicated good biological safety for DD NP HG in RA conditions. Taken together, these findings indicated that DD NP HG could achieve good anti-inflammatory activity and reverse cartilage disruption through a synergistic effect between two nanoparticulate forms of MTX and PEITC, which can effectively improve the drawbacks of their free forms.

A standardized nutraceutical supplement contributes to pain relief, improves quality of life and regulates inflammation in knee osteoarthritis patients; A randomized clinical trial

Osteoarthritis (OA) is a degenerative disease of the joints that affects greatly the elderly population and the health care systems and is on the increase due to aging and obesity. Interventions aim at palliative care and pharmaceutical therapies entail serious adverse events. Whereas polyphenols constitute a promising holistic approach in the arsenal of physicians, trials investigating biomarkers and questionnaires are scarce. As such, a randomized controlled trial (RCT) was conducted to evaluate the potency of a standardized polyphenolic supplement in the management of systemic inflammation, oxidative stress, pain and general quality of life (QoL) in patients with osteoarthritis. Sixty subjects were randomized to receive either a polyphenol supplement (curcuma phospholipid, rosemary extract, resveratrol, ascorbic acid), or an active comparator (ascorbic acid) twice, daily for 12 weeks. The group that received the polyphenols exhibited significantly lower symptoms of pain and improved physical function and QoL as it was depicted by validated questionnaires, compared to the control group. Furthermore, post intervention, inflammation was restrained in the polyphenol group. Since systemic inflammation promotes local inflammation, the decrease of pain herein might be attributed to the attenuation of systemic inflammation by the polyphenols.

Immunomodulatory effects and mechanisms of the extracts and secondary compounds of Zingiber and Alpinia species: a review

Zingiber and Alpinia species (family: Zingiberaceae) are popularly used in food as spices and flavoring agents and in ethnomedicine to heal numerous diseases, including immune-related disorders. However, their ethnomedicinal uses have not been sufficiently supported by scientific investigations. Numerous studies on the modulating effects of plants and their bioactive compounds on the different steps of the immune system have been documented. This review aimed to highlight up-to-date research findings and critically analyze the modulatory effects and mechanisms of the extracts and secondary compounds of several Zingiber and Alpinia species, namely, Zingiber officinale Roscoe, Z. cassumunar Roxb., Z. zerumbet (L.) Roscoe ex Sm., Alpinia galanga Linn., A. conchigera Griff, A. katsumadai Hayata, A. oxyphylla Miq., A. officinarum Hance, A. zerumbet (Pers.) Burtt. et Smith, and A. purpurata (Viell.) K. Schum. on the immune system, particularly via the inflammation-related signaling pathways. The immunomodulating activities of the crude extracts of the plants have been reported, but the constituents contributing to the activities have mostly not been identified. Among the extracts, Z. officinale extracts were the most investigated for their in vitro, in vivo, and clinical effects on the immune system. Among the bioactive metabolites, 6-, 8-, and 10-gingerols, 6-shogaol, and zerumbone from Zingiber species and cardamomin, 1'-acetoxychavicol acetate, yakuchinone, rutin, 1,8-cineole, and lectin from Alpinia species have demonstrated strong immunomodulating effects. More experimental studies using cell and animal models of immune-related disorders are necessary to further understand the underlying mechanisms, together with elaborate preclinical pharmacokinetics, pharmacodynamics, bioavailability, and toxicity studies. Many of these extracts and secondary metabolites are potential candidates for clinical development in immunomodulating agents or functional foods to prevent and treat chronic inflammatory disorders.

Chondroprotective Effects of Grapefruit (Citrus paradisi Macfad.) Juice in a Complete Freund's Adjuvant Rat Model of Knee Osteoarthritis

Osteoarthritis (OA) is a common disorder that can affect any joint in the human body. This study aimed to examine the anti-arthritic properties of high and low doses of grapefruit juice (GFJ), as grapefruit appears to contain anti-inflammatory biochemicals. Forty male Sprague-Dawley rats weighing 170-180 g were divided into five groups. These groups comprised the untreated control group and osteoarthritic (Osteo) rats administered intra-articular injections of Freund's complete adjuvant (CFA; 0.5 mL; 1 mg/mL) as follows: OA rats administered low doses of GFJ (Osteo+GFJ (low); 5 mL/kg body weight (BW)); OA rats administered high doses of GFJ (Osteo+GFJ (high); 27 mL/kg BW); and OA rats administered diclofenac sodium (Osteo+Diclo) as a reference drug. Injections of CFA induced OA, as indicated by a significant increase in the serum levels of the inflammatory biomarkers C-reactive protein (CRP), interleukin-1β (IL-1β), and (prostaglandin (PGE2), as well as matrix metalloproteinases (MMP-1) and cathepsin K. The synovial levels of glycosaminoglycans (GAGs), tumor necrosis factor (TNF-α), and interleukin 6 (IL-6) also increased, with a concomitant reduction in osteocalcin levels. The administration of either high or low doses of GFJ reduced CRP, IL-1β, PGE2, MMP-1, cathepsin K, and osteocalcin while increasing the synovial levels of GAGs, TNF-α, and IL-6, slowing cartilage degradation and boosting joint function. The results showed comparable histopathological and biochemical responses. A comparison of the treatments showed that high-dose GFJ had a greater chondroprotective effect than low-dose GFJ.

New Hyaluronic Acid from Plant Origin to Improve Joint Protection—An In Vitro Study

Background: In recent decades, hyaluronic acid (HA) has attracted great attention as a new treatment option for osteoarthritis. Classical therapies are not able to stop the cartilage degeneration process nor do they favor tissue repair. Nowadays, it is accepted that high molecular weight HA can reduce inflammation by promoting tissue regeneration; therefore, the aim of this study was to verify the efficacy of a new high molecular weight HA of plant origin (called GreenIuronic®) in maintaining joint homeostasis and preventing the harmful processes of osteoarthritis. Methods: The bioavailability of GreenIuronic® was investigated in a 3D intestinal barrier model that mimics human oral intake while excluding damage to the intestinal barrier. Furthermore, the chemical significance and biological properties of GreenIuronic® were investigated in conditions that simulate osteoarthritis. Results: Our data demonstrated that GreenIuronic® crosses the intestinal barrier without side effects as it has a chemical–biological profile, which could be responsible for many specific chondrocyte functions. Furthermore, in the osteoarthritis model, GreenIuronic® can modulate the molecular mechanism responsible for preventing and restoring the degradation of cartilage. Conclusion: According to our results, this new form of HA appears to be well absorbed and distributed to chondrocytes, preserving their biological activities. Therefore, the oral administration of GreenIuronic® in humans can be considered a valid strategy to obtain beneficial therapeutic effects during osteoarthritis.

Natural Approach in Osteoarthritis Therapy

Osteoarthritis (OA) is the most common joint disease worldwide, and its rising prevalence is supported by factors such as obesity and sedentariness. At the molecular level, it is considered an inflammatory disease that leads to the destruction of articular cartilage. Effective therapy to end the degenerative process of arthritis remains elusive, and most therapeutic tools prevent the progress or alleviate the symptoms. By now, medicines for OA are available for oral, topical, or intra-articular (IA) therapy and include analgesics, nonsteroidal anti-inflammatory drugs, corticosteroids, and hyaluronic acid. Compared with conventional oral administration, IA therapy has multiple advantages in terms of bioavailability, efficacy, and toxicity. This review aims to study the underlying beneficial effects of herbal medicine in OA therapy and to open new research perspectives. Herbal medicine administered orally or topically exhibits pharmacological properties that could be relevant for their beneficial effect in OA, mainly anti-inflammatory and antioxidant effects. There are few studies regarding IA injections of plant extracts/ compounds and none related to any combination with agents already used in the clinic. Designing natural pharmaceutical formulations with increased bioavailability that are safe, lack side effects, and are specifically tested, would be a plus for research on medicinal plants and a novelty for the clinic.

Chondroprotection of fruit peels in a monosodium iodoacetate-induced osteoarthritis rat model via downregulation of Col1A1

The potential of the fruit peels of mango, orange, cantaloupe, and pomegranate in the treatment of osteoarthritis (OA) was evaluated in a rat model. Their metabolic profiles were characterized using ultrahigh-performance liquid chromatography (UPLC)-electrospray ionization-mass spectroscopy and 66 albino rats were intra-articularly injected with monosodium iodoacetate in the knee joints. The extracts were orally administered at doses of 200 and 400 mg/kg for 28 days. Serum levels of IL-6 and tissue levels of cyclooxygenase-2 (COX-2), peroxisome proliferator-activated receptor-gamma (PPARγ), and alpha-smooth muscle actin (α-SMA) were measured using ELISA. COL1A1 expression was measured by quantitative polymerase chain reaction. Histopathological changes in the joints were examined. In the extracts, 85 metabolites were annotated, and the levels of interleukin (IL)-6, COX-2, α-SMA, malondialdehyde, and nitric oxide were significantly reduced, while PPARγ and glutathione levels were significantly raised in all treated groups compared to the OA group. All extracts downregulated the cartilage mRNA expressions for COL1A1 dose-dependently. Mango peel extract exhibited the best chondroprotective effect. The in silico study showed the link between mango extract metabolites and COX-2.

Inflammation and ROS in arthritis: management by Ayurvedic medicinal plants

Chronic joint inflammatory disorders like osteoarthritis and rheumatoid arthritis, which are manifested by joint dysfunction, show an upsurge in inflammation and oxidative stress. Although conventional anti-arthritic drugs are being used to relieve pain from arthritic symptoms, they usually cause severe side effects. Traditionally used Ayurvedic medicinal plants are a promising alternative for the management of arthritic symptoms, as they are safe and effective. Ayurvedic medicinal plants improve arthritic symptoms by reducing joint tenderness, joint pain, swelling, bone and cartilage damage, and increasing knee flexion, walking distance and sports activities. These beneficial effects of Ayurvedic medicinal plants on arthritis are mediated through various cellular mechanisms including inhibition of the inflammatory markers NF-κB, cytokines, adipokines, PGE2, NO, iNOS, COX-2, and MMPs and induction of antioxidant status by decreasing free radicals, lipid peroxidation, and myeloperoxidase, and increasing antioxidant enzymes, Nrf2, and HO-1. Thus, a strategy requires using these Ayurvedic medicinal plants to treat arthritis. This article describes the status of inflammation and oxidative stress in arthritic conditions. We also provide evidence that Ayurvedic medicinal plants and their bioactive components are highly effective in improving arthritic symptoms.

The Implication of Reactive Oxygen Species and Antioxidants in Knee Osteoarthritis

Knee osteoarthritis (KOA) is a chronic multifactorial pathology and a current and essential challenge for public health, with a negative impact on the geriatric patient's quality of life. The pathophysiology is not fully known; therefore, no specific treatment has been found to date. The increase in the number of newly diagnosed cases of KOA is worrying, and it is essential to reduce the risk factors and detect those with a protective role in this context. The destructive effects of free radicals consist of the acceleration of chondrosenescence and apoptosis. Among other risk factors, the influence of redox imbalance on the homeostasis of the osteoarticular system is highlighted. The evolution of KOA can be correlated with oxidative stress markers or antioxidant status. These factors reveal the importance of maintaining a redox balance for the joints and the whole body's health, emphasizing the importance of an individualized therapeutic approach based on antioxidant effects. This paper aims to present an updated picture of the implications of reactive oxygen species (ROS) in KOA from pathophysiological and biochemical perspectives, focusing on antioxidant systems that could establish the premises for appropriate treatment to restore the redox balance and improve the condition of patients with KOA.

Chondroprotection and Molecular Mechanism of Action of Phytonutraceuticals on Osteoarthritis

Osteoarthritis (OA) is a degenerative joint disease and an important cause of incapacitation. There is a lack of drugs and effective treatments that stop or slow the OA progression. Modern pharmacological treatments, such as analgesics, have analgesic effects but do not affect the course of OA. Long-term use of these drugs can lead to serious side effects. Given the OA nature, it is likely that lifelong treatment will be required to stop or slow its progression. Therefore, there is an urgent need for disease-modifying OA treatments that are also safe for clinical use over long periods. Phytonutraceuticals are herbal products that provide a therapeutic effect, including disease prevention, which not only have favorable safety characteristics but may have an alleviating effect on the OA and its symptoms. An estimated 47% of OA patients use alternative drugs, including phytonutraceuticals. The review studies the efficacy and action mechanism of widely used phytonutraceuticals, analyzes the available experimental and clinical data on the effect of some phytonutraceuticals (phytoflavonoids, polyphenols, and bioflavonoids) on OA, and examines the known molecular effect and the possibility of their use for chondroprotection.

The Effect of Nanocurcumin in Improvement of Knee Osteoarthritis: A Randomized Clinical Trial

OBJECTIVE

Osteoarthritis is a degenerative disease of the joints. Non-steroidal antiinflammatory drugs (NSAIDs) are being used for the treatment of osteoarthritis. However, their use is limited due to complications, such as gastrointestinal bleeding. Therefore, it is necessary to find alternative treatments for osteoarthritis. Recently, nanomicelle curcumin has been developed to increase the oral bioavailability of curcumin. The aim of this study was to evaluate the effect of nano curcumin on the alleviation of the symptoms of knee osteoarthritis patients.

METHODS

In this randomized, double-blind controlled trial, the intervention group was administered 40 mg of nanocurcumin capsule every 12 hours over a period of six weeks, and the control group received the placebo (similar components of nanomicelle curcumin capsules yet without curcumin). In the final analysis, 36 patients in the nanocurcumin group and 35 patients in the placebo group were enrolled. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was filled for patients in their first visit and at the end of six weeks. Differences were statistically significant at P-value < 0.05.

RESULTS

There were no significant differences between the two groups regarding gender, age, Kellgren score, and the duration of the disease before the intervention. A significant decrease was observed in the overall score, along with the scores of pain, stiffness and physical activity subscales of the WOMAC questionnaire in patients of the nano curcumin group compared with the placebo group.

CONCLUSION

Nanocurcumin significantly improves the symptoms of osteoarthritis patients.

Intra-articular Injection of Chitosan-Based Supramolecular Hydrogel for Osteoarthritis Treatment

BACKGROUND

Pain and cartilage destruction caused by osteoarthritis (OA) is a major challenge in clinical treatment. Traditional intra-articular injection of hyaluronic acid (HA) can relieve the disease, but limited by the difficulty of long-term maintenance of efficacy.

METHODS

In this study, an injectable and self-healing hydrogel was synthesized by in situ crosslinking of N-carboxyethyl chitosan (N-chitosan), adipic acid dihydrazide (ADH), and hyaluronic acid-aldehyde (HA-ALD).

RESULTS

This supramolecular hydrogel sustains good biocompatibility for chondrocytes. Intra-articular injection of this novel hydrogel can significantly alleviate the local inflammation microenvironment in knee joints, through inhibiting the inflammatory cytokines (such as TNF-α, IL-1β, IL-6 and IL-17) in the synovial fluid and cartilage at 2- and even 12-weeks post-injection. Histological and behavioral test indicated that hydrogel injection protected cartilage destruction and relieved pain in OA rats, in comparison to HA injection.

CONCLUSION

This kind of novel hydrogel, which is superior to the traditional HA injection, reveals a great potential for the treatment of OA.

Miconia albicans and Curcuma longa herbal medicines positively modulate joint pain, function and inflammation in patients with osteoarthritis: a clinical study

This study aims to evaluate the analgesic and modulating effect of Curcuma longa and Miconia albicans herbal medicines in knee's osteoarthritis (OA) treatment. This longitudinal study evaluated 24 patients with OA. The patients were divided into three groups: ibuprofen (1200 mg/day), C. longa (1000 mg/day) and M. albicans (1000 mg/day). The medications were applied orally for 30 days. The synovial fluid of the knee joint was collect at the first (day 0) and the last medical (day 30) consultation. The groups treated with herbal medicines presented the same results when compared to Ibuprofen. The comparison of the means of Total WOMAC for M. albicans before and after treatment presented a statistically significant difference (mean day 0 = 57.19; mean day 30 = 31.02) as well as variation of Total WOMAC for C. longa (mean day 0 = 54.79; mean day 30 = 37.08). The WOMAC Total and the VASP were compared, it was found that there was a significant decrease in the means in the C. longa and M. albicans groups, as well as in the Ibuprofen group after treatment. The study demonstrated that the treatment of knee OA with C. longa or M. albicans positively interferes with patients pain and functionality, decreased WOMAC and VASP scores, leading to functional improvement of these patients. This is the first clinical study demonstrating the analgesic and anti-inflammatory effect on knee osteoarthritis from M. albicans comparable to Ibuprofen drug.

Medicinal Plants and Phytochemicals Regulating Insulin Resistance and Glucose Homeostasis in Type 2 Diabetic Patients: A Clinical Review

Diabetes is a major health problem affecting more than four hundred million adults worldwide. The transition from normal glucose tolerance to type 2 diabetes (T2D) is preceded by increased Insulin resistance (IR), an independent predictor of the development of T2D in high risk (e.g. obese populations, pre-diabetes) individuals. Insulin deficiency resulting from increased IR results in progressive glucose homeostasis dysfunction. Data has shown that IR is affected by many different factors such as genetics, age, exercise, dietary nutrients, obesity, and body fat distribution. One of the most important factors is diet, which plays an essential role in addressing T2D and metabolic syndrome. Nutraceuticals and medicinal plants have been shown to have efficacy in preventing chronic diseases like cancer, non-alcoholic fatty liver disease (NAFLD), cardiovascular disease, diabetes mellitus and metabolic syndrome, likely through the anti-inflammatory properties found in nutraceuticals. However, the effect of these compounds, including traditional plant medicines, herbal formulations or their extracts on IR have not been systematically investigated. The objective of this review was to assess the reported effects of medicinal plants and bioactive natural compounds on IR. The findings confirm that most of the herbal bioactive compounds including resveratrol, garlic, curcumin, cinnamon, ginger, nuts, berberine, anthocyanin, soybean, flaxseed, vegetable oils, and soluble fibers have benefit in their efficacy for decreasing IR, fasting blood sugar (FBS), fasting insulin and HbA1c.

Dietary Supplementation with Palmitoyl-Glucosamine Co-Micronized with Curcumin Relieves Osteoarthritis Pain and Benefits Joint Mobility

Simple Summary

Canine osteoarthritis is a chronic degenerative joint disease and a major cause of elective euthanasia. The disorder increasingly limits joint motion, might cause lameness as well as pain, and impacts quality of life. An unmet need remains for safe and effective therapies for osteoarthritis. Palmitoyl-glucosamine and curcumin are used in animal nutrition. A co-micronized formulation, with the two substances being jointly processed to reduce their particle size and increase the extent to which they can be absorbed, is currently available on the European market. The present study investigated if this formulation could relieve joint pain and benefit mobility. Two well-established rat models of inflammation and osteoarthritis pain were used. Results from the first set of experiments showed that the dietary supplement relieved experimentally induced paw edema, infiltration of inflammatory cells, and decreased sensitivity to painful stimuli (thermal hyperalgesia). In the osteoarthritis model, the supplement proved to protect joint cartilage against degradation and successfully address neuropathic pain (i.e., pain from normally non-painful stimuli). Locomotor function recovered by 45% under supplement administration. The present findings suggest that the dietary supplement with palmitoyl-glucosamine co-micronized with curcumin might help manage osteoarthritis.

Abstract

Chronic mixed pain and orthopedic dysfunction are the most frequently associated consequences of canine osteoarthritis (OA). An unmet need remains for safe and effective therapies for OA. Palmitoyl-glucosamine (PGA) and curcumin are safe and naturally occurring compounds whose use is limited by poor bioavailability. Micronization is an established technique to increase bioavailability. The aim of this study was to investigate if the dietary supplementation with PGA co-micronized with curcumin (PGA-Cur, 2:1 ratio by mass) could limit pathologic process in two well-established rat models of inflammation and OA pain, i.e., subplantar carrageenan (CAR) and knee injection of sodium monoiodoacetate (MIA), respectively. In CAR-injected animals, a single dose of PGA-cur significantly reduced paw edema and hyperalgesia, as well as tissue damage and neutrophil infiltration. The repeated administration of PGA-Cur three times per week for 21 days, starting the third day after MIA injection resulted in a significant anti-allodynic effect. Protection against cartilage damage and recovery of locomotor function by 45% were also recorded. Finally, PGA-cur significantly counteracted MIA-induced increase in serum levels of TNF-α, IL-1β, NGF, as well as metalloproteases 1, 3, and 9. All the effects of PGA-Cur were superior compared to the compounds used singly. PGA-Cur emerged as a useful dietary intervention for OA.

Unraveling Natural Products' Role in Osteoarthritis Management-An Overview

The natural process of aging gradually causes changes in living organisms, leading to the deterioration of organs, tissues, and cells. In the case of osteoarthritis (OA), the degradation of cartilage is a result of both mechanical stress and biochemical factors. Natural products have already been evaluated for their potential role in the prevention and treatment of OA, providing a safe and effective adjunctive therapeutic approach. This review aimed to assess the therapeutic potential of natural products and their derivatives in osteoarthritis via a systematic search of literature after 2008, including in vitro, in vivo, ex vivo, and animal models, along with clinical trials and meta-analysis. Overall, 170 papers were obtained and screened. Here, we presented findings referring to the preventative and therapeutic potential of 17 natural products and 14 naturally occurring compounds, underlining, when available, the mechanisms implicated. The nature of OA calls to initially focus on the management of symptoms, and, in that context, several naturally occurring compounds have been utilized. Underlying a global need for more sustainable natural sources for treatment, the evidence supporting their chondroprotective potential is still building up. However, arriving at that kind of solution requires more clinical research, targeting the implications of long-term treatment, adverse effects, and epigenetic implications.

The extract from the roots of Rose odorata sweet var. gigantean (Coll. et Hemsl.) Rehd. et Wils attenuates DSS-induced ulcerative colitis by regulating the Nrf2/NF-κB signaling pathways

Ulcerative colitis (UC) is a chronic non-specific inflammatory bowel disease. Many natural medicines or ethnic drugs have been proven to be effective and beneficial in the treatment of UC. Among these, the root of Rose odorata sweet var. gigantean (Coll. et Hemsl.) Rehd. et Wils. (ROS), a kind of Yi nationality medicine called "GU-GONG-GUO," has been shown to be useful as a therapeutic agent for sputum and diarrhea. However, the effects and mechanisms of ROS extract (ROE) on UC remain relatively unknown. The aim of this study was to explore the protective effects and the underlying mechanisms of ROE on UC. First, we established a dextran sulfate sodium (DSS)-induced experimental colitis mouse model and then evaluated the anti-inflammatory effects of ROE in vivo. Then, RAW264.7 cells were stimulated with lipopolysaccharide (LPS) in the presence or absence of ROE to explore its mechanisms in vitro. It was found that ROE attenuated DSS-induced colon length shortening, body weight loss, and colonic pathological damage. Furthermore, ROE inhibited the activity of nitric oxide synthase (NOS), myeloperoxidase (MPO), and malondialdehyde (MDA). Also, ROE decreased several LPS-induced inflammatory cytokines including TNF-α, IL-6, and IL-1β in RAW264.7. In addition, ROE inhibited the expression of p-NF-κB, p-IKKα/β, and Keap1 proteins and increased the expression of Nrf2 and HO-1 proteins. Our study suggested that ROE prevented DSS-induced colitis though the Nrf2/NF-κB pathway. Overall, it can be concluded that ROE may be a promising and effective agent for UC.

Thermoresponsive Hyalomer intra-articular hydrogels improve monoiodoacetate-induced osteoarthritis in rats

Osteoarthritis (OA) is characterized by degenerative knees, fingers and hip joints. In OA joints, the concentration and polymerization of hyaluronic acid (HA) are changed; affecting the viscosity of the synovial fluid. Replenishing HA synovial fluid content, along with an anti-inflammatory drug could be a cost-effective strategy. As free drugs are rapidly cleared out of the synovial fluid, we aimed to prepare Hyalomer in situ forming gel for intra-articular (IA) injection. Hyalomer contains poloxamer 407 (PX) as thermogelling agent, HA, and diclofenac potassium (DK) as an anti-inflammatory. Hyalomer formulations were prepared and characterized in terms of sol-gel transition, gelation time, in vitro release and 3-month stability. The selected Hyalomer formula was injected IA in OA rat model, in comparison to its individual components. The optimized Hyalomer formulation showed 25% DK release after 24 h and 40% after 4 days. The gelation time was 40 ± 2.08 s and gelation temperature was 26 ± 1.87 °C. Hyalomer maintained the percentage drug release and DK content after 3-months storage. In OA rats, Hyalomer showed the highest anti-nociceptive and anti-edematous effect. Both radiography and histopathology revealed regenerated cartilage profile in Hyalomer-treated group. combining IA HA and diclofenac in thermoresponsive gel represents a promising therapeutic alternative for OA.

The Oxidative Stress in Knee Osteoarthritis Patients. An Attempt of Evaluation of Possible Compensatory Effects Occurring in the Disease Development

Background and Objective: Osteoarthritis (OA) is a disorder of the musculoskeletal system resulting in worsening of life condition. The research revealed the involvement of oxidative stress into both OA pathogenesis and the effects of therapeutic agents applied in OA cases. The activities of the most important antioxidant enzymes, namely superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and total antioxidant status (TAS), in blood of the knee OA patients were studied, with the aim of clarifying which enzymatic antioxidants are involved into osteoarthritis (OA)-related oxidative stress and whether any compensatory effects occur. The results were additionally analyzed with regard to gender. Methods: Whole blood SOD (U/mL), plasma GPx (U/L) and CAT (U/mL) activities as well as plasma TAS (mmol/L)) in knee OA patients were investigated. Sixty-seven patients (49 females and 18 males) with primary knee OA were enrolled. The control comprised 21 subjects (10 females and 11 males) free of osteoarthritis or inflammation. Results: TAS was decreased in OA subjects (4.39 ± 0.53 vs. 4.70 ± 0.60), with this effect being more significant in OA females (4.31 ± 0.51 vs. 5.02 ± 0.54). GPx was depressed in all OA patients (518 ± 176 vs. 675 ± 149). In both genders, GPx was decreased, significantly in males (482 ± 185 vs. 715 ± 105). SOD was decreased in all OA patients (109 ± 32 vs. 127 ± 42). CAT showed no difference in all OA subjects vs. control, while in OA females it was depleted (20.2 (11.6–31.6) vs. 38.5 (27.9–46.6)) and in OA men it increased (26.9 (23.3–46.5) vs. 14.0 (7.0–18.6)). Conclusions: The obtained results suggest that in men some compensatory mechanisms towards OA-related oxidative stress occurred. Based on the obtained data, the introduction of antioxidant supplements into OA therapy could be suggested with further research concerning the choice of agents.

Omi/HtrA2 Protease Associated Cell Apoptosis Participates in Blood-Brain Barrier Dysfunction

Background: Omi/HtrA2 is a proapoptotic mitochondrial serine protease involved in caspase-dependent cell apoptosis, translocating from mitochondria to the cytosol after an apoptotic insult. Our previous study indicated pre-treatment with UCF-101, a specific inhibitor of Omi/HtrA2, could significantly reduce neuronal apoptosis and attenuate sepsis-induced cognitive dysfunction. Various hypotheses involving blood-brain-barrier (BBB) disruption have been proposed to account for sepsis-associated encephalopathy (SAE). Here, we attempted to explore whether interference of Omi/HtrA2 by RNA interference or UCF-101 pre-treatment can improve sepsis-induced disruption of BBB using human cerebral microvascular endothelial cell line (hCMEC/D3) in vitro and if so, to explore mechanisms involved Omi/HtrA2 protease mediates BBB disruption in SAE.

Methods: hCMEC/D3 cell monolayers were intervened by different concentrations of LPS (0–50 μg/mL) over experimental period. Pharmacological or gene interventions (by silencing RNA of Omi/HtrA2) were used to study molecular mechanisms involved in sepsis-associated Omi/HtrA2 translocation, cell apoptosis and BBB dysfunction. BBB function was assessed by trans-endothelial electrical resistance (TEER) and permeability to labeled dextrans (FITC-4kDa). Tight junction (TJ) integrity was assessed by immunofluorescence, western blotting and transmission electron microscopic (TEM) analyses. Apoptosis was determined using flow cytometry and TUNEL assay. Mitochondrial membrane potential (MMP) and oxidative stress were also investigated.

Results: LPS affects hCMEC/D3 TJ permeability in a concentration- and time-dependent manner. LPS intervention resulted in a significant disruption of BBB, as manifested by decreased TEER (by ~26%) and a parallel increased paracellular permeability to FITC- (4kDa) dextrans through hCMEC/D3 monolayers. The inhibition of Omi/HtrA2 by UCF-101 or Omi/HtrA2 shRNA reduced LPS-induced brain endothelial cell apoptosis, and resulted in significant improvement on LPS-induced BBB disruption as well as decreased occludin, claudin-5 and ZO-1 expressions. Omi/HtrA2 manipulated endothelial cell apoptosis by shifting into cytosol and inducing X-linked inhibitor of apoptosis protein (XIAP) degradation. UCF-101 administration or Omi/HtrA2 shRNA intervention did attenuate the degradation of XIAP, Poly ADP-ribose polymerase (PARP) cleavage, and caspase-3 cleavage. However, only UCF-101 partly prevented the mobilization of Omi/HtrA2 from the mitochondria to the cytosol after LPS intervention. That abrogation of Omi/HtrA2 by UCF-101 or Omi/HtrA2 shRNA resulted in a significant improvement on LPS-induced decrease of MMP. Oxidative stress was significantly increased in the LPS treated group compared to the control or NC-shRNA group. However, abrogation of Omi/HtrA2 by UCF-101 or Omi/HtrA2 shRNA did not significantly improve oxidative injury.

Conclusions: Our study indicated an important role of Omi/HtrA2 in manipulating LPS-induced cell apoptosis and BBB integrity by translocating from mitochondria into cytosol in brain endothelial cells. Omi/HtrA2 induced mitochondrial pathway apoptosis, which involves inhibition of an important antiapoptotic protein XIAP and influence on MMP. Therapeutic methods that inhibit Omi/HtrA2 function may provide a novel therapeutic measure to septic encephalopathy.

Hyaluronic acid-chitosan nanoparticles encoding CrmA attenuate interleukin-1β induced inflammation in synoviocytes in vitro

Osteoarthritis (OA) is a common degenerative joint disease characterized by inflammation of synoviocytes and degradation of cartilage. In the present study, hyaluronic acid/chitosan (HA/CS) nanoparticles were used as a vehicle for gene therapy of OA, and the cytokine response modifier A (CrmA) pDNA was proposed as the target gene. The HA/CS/pCrmA nanoparticles were prepared and the characteristics of the nanoparticles were examined. The nanoparticles were spherical, and the smallest size was obtained with the HA:CS weight ratio of 1:4. The release analysis exhibited a constant release over 29 days. The pDNA was completely combined with HA/CS nanoparticles and the HA/CS nanoparticles protected pDNA from degradation. Subsequently, rat synoviocytes were transfected with HA/CS/pDNA nanoparticles, and the results demonstrated that the HA/CS nanoparticles were able to improve the transfection capacity of pDNA. The cytotoxicity of the HA/CS/pDNA nanoparticles was additionally detected using a MTS assay to ensure that the HA/CS nanoparticle was a safe carrier. To additionally investigate the effects of HA/CS/pCrmA nanoparticles on synoviocytes in OA, the MMP‑3 and MMP‑13 gene expression levels were detected at the gene and protein expression levels. These results indicated that the HA/CS/pCrmA nanoparticles attenuated interleukin‑1β‑mediated inflammation in synoviocytes. It was concluded that the HA/CS/pCrmA nanoparticles may provide a novel approach to the treatment of OA.

Acamprosate Protects Against Adjuvant-Induced Arthritis in Rats via Blocking the ERK/MAPK and NF-κB Signaling Pathway

Osteoarthritis is a type of joint disease that results from the breakdown of joint cartilage and underlying bone and is believed to be caused by mechanical stress on the joint and low-grade inflammatory processes. Acamprosate significantly ameliorates the pathological features of experimental autoimmune encephalomyelitis due to its anti-inflammatory effect. The aims of the present study were to investigate the anti-arthritis activities of acamprosate and elucidate the underlying mechanisms. Adjuvant-induced arthritis (AIA) was induced by intradermal injection of complete Freund's adjuvant. Male Wistar rats were randomly divided into five groups: (1) sham control group, (2) AIA group, (3) acamprosate 10 mg/kg (AIA + ACA10), (4) acamprosate 30 mg/kg (AIA + ACA30), and (5) acamprosate 100 mg/kg (AIA + ACA100). Paw swelling and the arthritis index were measured, and the production of IL-1β, IL-6, and TNF-α was detected by ELISA in serum. The expression of inflammation-related molecules, including c-Raf, ERK1/2, and NF-κB, was determined by Western blotting. We found that acamprosate significantly suppressed paw swelling and the arthritis index in AIA rats. Moreover, acamprosate also significantly suppressed the production of TNF-α, IL-1β, and IL-6 in serum, which is elevated by AIA induction. Finally, acamprosate inhibited p-c-Raf and p-ERK1/2 and NF-κB activation after AIA treatment. These results indicate that acamprosate has an anti-inflammatory effect on adjuvant-induced arthritic rats via inhibiting the ERK/MAPK and NF-κB signaling pathways, and acamprosate may serve as a promising novel therapeutic agent for osteoarthritis.

Selection and Investigation of a Primate Model of Spontaneous Degenerative Knee Osteoarthritis, the Cynomolgus Monkey (Macaca Fascicularis)

BACKGROUND The aim of this study was to identify a primate model of degenerative knee osteoarthritis (KOA) that may be more relevant for research studies on degenerative KOA in humans. MATERIAL AND METHODS Sixteen specific-pathogen-free (SPF) male cynomolgus monkeys (Macaca fascicularis) were divided into group A (n=8), an old group (22.0-25.3 years of age), and group B (n=8), a young group (3.0-5.2 years of age). For each primate, the behavior was observed, knee circumference was measured, knee joint X-rays were performed, and peripheral blood white blood cell (WBC) counts were measured, and the Kellgren and Lawrence (K-L) system was used for the classification of osteoarthritis. An enzyme-linked immunoassay (ELISA) was performed on knee joint fluid to measure levels of interleukin (IL)-1β, transforming growth factor (TGF)-β1, and matrix metalloproteinase (MMP)13. Changes in articular cartilage were evaluated using the Brittberg score and the Mankin histopathology grading score, respectively. Quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blot were used to measure the expression of the NOTCH3, JAG1, and ACAN genes in knee cartilage specimens, and the findings in the two groups of primates were compared. RESULTS Seven old aged primates in group A were compared with group B, and showed significant differences in WBC count, synovial fluid IL-1β, TGF-β1, and MMP13 levels, expression levels of the NOTCH3, JAG1, and ACAN genes in knee cartilage specimens, and in the Brittberg and Mankin scores (all, P<0.05). CONCLUSIONS Cynomolgus monkeys (Macaca fascicularis) might be a model for age-related degenerative KOA.