Chicken type II collagen induced immune balance of main subtype of helper T cells in mesenteric lymph node lymphocytes in rats with collagen-induced arthritis

Ternary complex of soluble undenatured type II collagen-hydrophobic phytochemical-chondroitin sulfate facilitates high stability and targeted intestinal release properties to active substance

Researchers have reported that soluble undenatured type II collagen (SC II) and hydrophobic phytochemicals (HPs) can ameliorate osteoarthritis (OA) through several mechanisms. However, the solubility of HPs, the stability of SC II, and the bio-accessibility of both need to be greatly improved before they can be successfully used for this purpose. In this study, two common HPs, curcumin (CUR, a hydrophobic polyphenol) and astaxanthin (AST, a carotenoid), were first loaded into SC II, which was then complexed with chondroitin sulfate (CS) to form ternary complexes: SC II-HP-CS. The results showed that SC II had the highest loading capacity for CUR (19.00 ± 0.76 μg/mg) and AST (21.15 ± 1.67 μg/mg) at pH 2.0. The CUR and AST bound to the SC II through non-covalent interactions (mainly hydrophobic interaction) and they both existed in an amorphous form within the complexes. In addition, the binding affinity and hydrophobic interaction between SC II and CUR was higher than those of AST. The thermal stability of the SC II-CUR-CS (Td = 118.0 ± 2.1 °C) and SC II-AST-CS (Td = 118.8 ± 3.5 °C) complexes were significantly higher than that of the SC II-CUR (Td = 104.27 ± 0.28 °C) and SC II-AST (Td = 103.8 ± 1.6 °C) complexes. SC II-HP complexes dissolved in gastric fluids, resulting in serious degradation of the SC II, while SC II-HP-CS complexes existed in an insoluble form to protect the triple helix structure of SC II (24-46 % retained). The CUR release (94.2 ± 5.8 %) and the free radical scavenging activity (84.6 ± 5.3 %) of SC II-CUR-CS was relatively high after 6 h of intestinal digestion, while AST in SC II-AST and SC II-AST-CS had low solubility and antioxidant activity. Therefore, the ternary complex of SC II-HP-CS was more advantageous as multifunctional delivery systems for the encapsulation, protection, and controlled release of hydrophobic polyphenols, which may provide guidance for the synergistic use of hydrophobic polyphenols and SC II to improve OA.

Undenatured type II collagen protects against collagen-induced arthritis by restoring gut-joint homeostasis and immunity

Oral administration of harmless antigens can induce suppression of reactive immune responses, a process that capitalises on the ability of the gastrointestinal tract to tolerate exposure to food and commensal microbiome without triggering inflammatory responses. Repeating exposure to type II collagen induces oral tolerance and inhibits induction of arthritis, a chronic inflammatory joint condition. Although some mechanisms underlying oral tolerance are described, how dysregulation of gut immune networks impacts on inflammation of distant tissues like the joints is unclear. We used undenatured type II collagen in a prophylactic regime -7.33 mg/kg three times/week- to describe the mechanisms associated with protective oral immune-therapy (OIT) in gut and joint during experimental Collagen-Induced Arthritis (CIA). OIT reduced disease incidence to 50%, with reduced expression of IL-17 and IL-22 in the joints of asymptomatic mice. Moreover, whilst the gut tissue of arthritic mice shows substantial damage and activation of tissue-specific immune networks, oral administration of undenatured type II collagen protects against gut pathology in all mice, symptomatic and asymptomatic, rewiring IL-17/IL-22 networks. Furthermore, gut fucosylation and microbiome composition were also modulated. These results corroborate the relevance of the gut-joint axis in arthritis, showing novel regulatory mechanisms linked to therapeutic OIT in joint disease.

High gastrointestinal digestive stability endows chondroitin sulfate-soluble undenatured type II collagen complex with high activity: Improvement of osteoarthritis in rats

Previously, we prepared a chondroitin sulfate-soluble undenatured type II collagen complex (CS-SC II) with low salt content. This paper further explored the differences between CS-SC II and SC II in terms of gastrointestinal digestive characteristics and osteoarthritis (OA) improvement. In vitro and in vivo experiments showed that the gastric digestive stability of CS-SC II was high under both pH 2.0 and pH 3.0, the α1 chain and triple helix structure of type II collagen retained >60 %. However, SC II had high gastric digestive stability only under pH 3.0. Furthermore, intestinal digestion had little effect on α1 chains of CS-SC II and SC II, and distribution experiments showed that they might exert their biological activities in the intestine. CS-SC II had obvious improvement in OA rats at 1.0 mg/kg/d, that is, the joint swelling was significantly reduced and the weight-bearing ratio of the right hind limb was increased to 49 %, which was close to that of 4.0 mg/kg/d SC II. The wear of articular cartilage, Mankin and OARSI scores of rats in CS-SC II group were significantly reduced. The effects of low-dose CS-SC II on the proportion of regulatory T cells (Treg), mRNA expression of OA key biomarkers (Il6, Ccl7, MMP-3 and MMP13) and signaling pathway genes (NF-κB, AKT or AMPKα) were comparable to those of high-dose SC II. These results showed that CS-SC II might have greater potential to improve OA at a lower dose than SC II due to its high gastrointestinal digestive stability at a wide range of pH conditions.

Differences between soluble and insoluble undenatured type II collagen in improving osteoarthritis in rats and their potential mechanisms

Our previous research showed that soluble (SC II) and insoluble (IC II) undenatured type II collagen had significant differences during gastrointestinal digestion in vitro, and SC II exposed more type II collagen with triple helix structure. However, the differences in their in vivo digestive characteristics, improvement on osteoarthritis (OA), and possible mechanisms have not been elucidated. The aim of this study was to explore these issues. After oral administration of SC II and IC II, the joint swelling of OA rats significantly reduced, and the weight bearing ratio of right hind limb significantly increased, especially in SC II group (raised to 48%). The Mankin and OARSI scores decreased by 35% and 48% in SC II group, respectively. SC II and IC II increased the mRNA expression of anti-inflammatory factors and the proportion of regulatory T cells (Treg). Importantly, type II collagen released by IC II during in vivo gastrointestinal digestion was far less than SC II, which explained the higher ability of SC II to induce immune tolerance in small intestine than IC II. Bioinformatics analysis showed that the differential genes between model and control were significantly enriched in PI3K/AKT, PPAR and AMPK signalling pathways, and 24 hub genes were analyzed. SC II significantly down-regulated the mRNA expression of Il6, Ccl7, NF-κB, AKT and up-regulated the mRNA expression of Scd1. These results showed that SC II was superior to IC II in improving OA by inducing immune tolerance and could regulate key biomarkers and signalling pathways in OA rats.

Undenatured type II collagen and its role in improving osteoarthritis

Osteoarthritis (OA) is a degenerative joint disease, affecting 32.5 million US adults or 242 million people worldwide. There is no cure for OA. Many animal and clinical trials showed that oral administration of undenatured type II collagen could significantly reduce the incidence of OA or alleviate the symptoms of articular cartilage. Type II collagen is an important component of cartilage matrix. This article reviewed research progress of undenatured type II collagen including its methods of extraction and preparation, structure and characterization, solubility, thermal stability, gastrointestinal digestive stability, its role in improving OA, and the mechanism of its action in improving OA. Type II collagen has been extensively explored for its potential in improving arthritis. Methods of extraction of type II collagen are inefficient and tedious. The method of limited enzymatic hydrolysis is mainly used to prepare soluble undenatured type II collagen (SC II). The solubility, thermal and gastrointestinal digestive stability of SC II are affected by the sources of raw material, pH, salt ions, and temperature. Oral administration of undenatured type II collagen improves OA, whereas its activity is affected by the sources, degree of denaturalization, intervention methods and doses. However, the influence of the structure of undenatured type II collagen on its activity and the mechanism are unclear. The findings in this review support that undenatured type II collagen can be used in the intervention or auxiliary intervention of patients with OA.

Pharmatherapeutic Treatment of Osteoarthrosis-Does the Pill against Already Exist? A Narrative Review

The aim of this narrative review is to summarize the current pharmacotherapeutic treatment options for osteoarthritis (OA). Is therapy still mainly symptomatic or does the pill against arthrosis already exist? Causal and non-causal, as well as future therapeutic approaches, are discussed. Various surgical and non-surgical treatment options are available that can help manage symptoms, slow down progression, and improve quality of life. To date, however, therapy is still mainly symptomatic, often using painkilling and anti-inflammatory drugs until the final stage, which is usually joint replacement. These "symptomatic pills against" have side effects and do not alter the progression of OA, which is caused by an imbalance between degenerative and regenerative processes. Next to resolving mechanical issues, the goal must be to gain a better understanding of the cellular and molecular basis of OA. Recently, there has been a lot of interest in cartilage-regenerative medicine and in the current style of treating rheumatoid arthritis, where drug therapy ("the pill against") has been established to slow down or even stop the progression of rheumatoid arthritis and has banned the vast majority of former almost regular severe joint destructions. However, the "causal pill against" OA does not exist so far. First, the early detection of osteoarthritis by means of biomarkers and imaging should therefore gain more focus. Second, future therapeutic approaches have to identify innovative therapeutic approaches influencing inflammatory and metabolic processes. Several pharmacologic, genetic, and even epigenetic attempts are promising, but none have clinically improved causal therapy so far, unfortunately.

Efficacy and Safety of Dietary Undenatured Type II Collagen on Joint and Motor Function in Healthy Volunteers: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Study

Prevalence of osteoarthritis (OA) is increasing alarmingly worldwide. Slowing down the progression of OA and diverse locomotive organ disorders is gaining interest in improving the quality of life (QOL) and extending healthy life-span. In a pilot study, intake of a small amount of undenatured type II collagen exhibited suppression of damage to the articular cartilage via oral immune tolerance. It also demonstrated improvement of knee and joint flexibility and mobility with continued intake of undenatured type II collagen (NEXT-II®) derived from chicken sternum cartilage. This randomized, double-blind, placebo-controlled, parallel-group clinical investigation (RCT) evaluated the efficacy and safety of 12 weeks of regular intake of NEXT-II^® on joint and motor function in healthy Japanese male and female participants (aged 20 to <75 years).

Sixty-four participants were randomized to receive either NEXT-II^® (undenatured type II collagen 3.2 mg/d) or placebo over a period of 12 consecutive weeks. Efficacy on joint and motor functions were evaluated measuring knee passive range of motion as the primary outcome; the Japan Knee Osteoarthritis Measure (JKOM), Visual Analog Scale (VAS) for knee discomfort, and motor functions (10-meter walking and stair-climbing test) as the secondary outcomes; and Japan Low back pain Evaluation Questionnaire (JLEQ) and VAS for lower back discomfort as the exploratory outcomes.

Fifty-eight participants (placebo = 28; NEXT-II^® group = 30) completed the study. In the assessment of knee passive range of motion, significant improvements in "flexion" and "flexible angle (range)" were observed in the NEXT-II^® group at 4, 8, and 12 weeks of treatment. NEXT-II^® induced significant improvements in JKOM, VAS for knee and lower back discomfort, 10-meter walking test, stair-climbing test, and JLEQ.

Results demonstrate that undenatured type II collagen is safe and efficacious in improving knee flexibility and mobility, reducing knee and lower back pain, and enhancing motor function.

Management of Osteoarthritis and Joint Support Using Feed Supplements: A Scoping Review of Undenatured Type II Collagen and Boswellia serrata

In the multimodal management of osteoarthritis (OA) in recent decades, the use of feed supplements to maintain joint cartilage has been advocated. The aim of this scoping review is to present the results found in the veterinary literature on the use of undenatured type II collagen and Boswellia serrata in dogs, specifically its use in dogs with clinical signs of OA, healthy dogs after intense exercise or dogs with diseases that predispose the individual to OA. For this purpose, a literature review was carried out using the electronic databases PubMed, Web of Science and Google Scholar, from which a total of 26 records were included in this review: fourteen evaluating undenatured type II collagen, ten evaluating Boswellia serrata and two evaluating the combination of undenatured type II collagen and Boswellia serrata. The review of the records showed that undenatured type II collagen decreases the clinical signs associated with OA, improving the general clinical state with a reduction in the degree of lameness and increase in physical activity or mobility. Evaluating the response to supplementation with Boswellia serrata alone is complicated due to the limited publication of studies and variations in the purity and compositions of the products used, but in general terms, its combination with other feed supplements produces benefits by relieving pain and reducing the clinical signs of OA in dogs. The combination of both in the same product provides results similar to those obtained in undenatured type II collagen studies. In conclusion, undenatured type II collagen and Boswellia serrata are considered a valid option for the multimodal approach to the management of OA and for improving activity during intense exercise, but more studies are needed to conclude whether or not it prevents OA in dogs.

1H-NMR metabolomic profile of healthy and osteoarthritic canine synovial fluid before and after UC-II supplementation

The aim of the study was to compare the metabolomic synovial fluid (SF) profile of dogs affected by spontaneous osteoarthritis (OA) and supplemented with undenatured type II collagen (UC-II), with that of healthy control dogs. Client-owned dogs were enrolled in the study and randomized in two different groups, based on the presence/absence of OA (OA group and OA-free group). All dogs were clinically evaluated and underwent SF sampling for ¹H-Nuclear Magnetic Resonance spectroscopy (¹H-NMR) analysis at time of presentation. All dogs included in OA group were supplemented with UC-II orally administered for 30 days. After this period, they were reassessed (OA-T30). The differences in the ¹H-NMR metabolic SFs profiles between groups (OA-free, OA-T0 and OA-T30) were studied. The multivariate statistical analysis performed on SFs under different conditions (OA-T0 vs OA-T30 SFs; OA-T0 vs OA-free SFs and OA-T30 vs OA-free SFs) gave models with excellent goodness of fit and predictive parameters, revealed by a marked separation between groups. β-Hydroxybutyrate was identified as a characteristic compound of osteoarthritic joints, showing the important role of fat metabolism during OA. The absence of β-hydroxybutyrate after UC-II supplementation suggests the supplement's effectiveness in rebalancing the metabolism inside the joint. The unexpectedly high level of lactate in the OA-free group suggests that lactate could not be considered a good marker for OA. These results prove that ¹H-NMR-based metabolomic analysis is a valid tool to study and monitor OA and that UC-II improves clinical symptoms and the SF metabolic profile in OA dogs.

Molecular Mechanisms of Action of Undenatured Type II Collagen: Experimental and Clinical Evidence

In the treatment of joint diseases, including osteoarthritis (OA), the use of standardized extracts of undenatured type II collagen (UDC-II) is promising. It is known that UDC-II is involved in the regulation of innate and adaptive immunity (reduction of autoimmune reactions that stimulate cartilage degradation) and in the reduction of chronic inflammation activity (modulation of cytokines and prostaglandins). The effect of UDC-II on discoidin receptors of chondrocytes helps to prevent structural disorders of the cartilage connective tissue. Experimental and clinical studies have shown that under the influence of standardized UDC-II, there is an increase in the proportion of regulatory CD4+ T cells, a decrease in the levels of pro-inflammatory cytokines, such as interleukin (IL) 1β, IL6, tumor necrosis factor α, CRP, prostaglandins in the blood, as well as matrix metalloproteinase 3 and NF-κB expression in cartilage. The use of UDC-II in OA leads to a significant reduction in pain, an increase in the range of joint motion, an improvement in joint function according to WOMAC and quality of life.

 

A 2022 Systematic Review and Meta-Analysis of Enriched Therapeutic Diets and Nutraceuticals in Canine and Feline Osteoarthritis

With osteoarthritis being the most common degenerative disease in pet animals, a very broad panel of natural health products is available on the market for its management. The aim of this systematic review and meta-analysis, registered on PROSPERO (CRD42021279368), was to test for the evidence of clinical analgesia efficacy of fortified foods and nutraceuticals administered in dogs and cats affected by osteoarthritis. In four electronic bibliographic databases, 1578 publications were retrieved plus 20 additional publications from internal sources. Fifty-seven articles were included, comprising 72 trials divided into nine different categories of natural health compound. The efficacy assessment, associated to the level of quality of each trial, presented an evident clinical analgesic efficacy for omega-3-enriched diets, omega-3 supplements and cannabidiol (to a lesser degree). Our analyses showed a weak efficacy of collagen and a very marked non-effect of chondroitin-glucosamine nutraceuticals, which leads us to recommend that the latter products should no longer be recommended for pain management in canine and feline osteoarthritis.

Evaluation of clinical efficacy of undenatured type II collagen supplementation compared to cimicoxib and their association in dogs affected by natural occurring osteoarthritis

The aim of the study was to evaluate the clinical efficacy of 30 days treatment of undenatured type II collagen(UC-II®), compared to cimicoxib and to their combination, in osteoarthritic dogs. Client-owned dogs were enrolled in a clinical, randomized, controlled and prospective study. Posture, lameness, pain, range of motion and x-ray of affected joint(s) were evaluated and scored based on severity (CLINICAL score). The Liverpool Osteoarthritis in Dogs survey was used to score the owner evaluation of dog's mobility (LOAD score and MOBILITY score). Osteoarthritis (OA) stage was defined through the Canine Osteoarthritis Staging tool (COAST). After diagnosis (T0), all patients were randomly assigned to different treatment groups: C group = cimicoxib 2 mg/kg/day orally OS, F group = UC-II® 1 tablet per day OS; C + F group = cimicoxib-UC-II® at the same previous dosages; CTR group = dogs who didn't received any treatment. All treatments were administered for 30 days. Seventy-six dogs completed the study. LOAD score was recorded significant lower after treatment for each group, with a reduction in percentage of 29.5% for C, 31.4% for F, 21.1% for C + F. LOAD score was lower in C(P = 0.04), F(P = 0.001) and C + F(P = 0.009) group at T30 than CTR group. MOBILITY and CLINICAL scores were significantly lower in all groups at T30, when compared to T0. MOBILITY score was lower than CTR in C(P = 0.02) and F(P = 0.01); CLINICAL score was lower in C + F(P = 0.016). The present findings prove that the treatment with UC-II®, cimicoxib and their combination provide significant reduction in clinical signs associated with OA.

Effect of Different Collagen on Anterior Cruciate Ligament Transection and Medial Meniscectomy-Induced Osteoarthritis Male Rats

Osteoarthritis (OA) is a common type of arthritis characterized by degeneration of the articular cartilage and joint dysfunction. Various pharmacological and non-pharmacological techniques have been used to manage these diseases. Due to the diverse therapeutic properties of marine collagen, it has received considerable attention in its pharmacological application. Thus, the purpose of this study was to compare the efficacy of jellyfish collagen, collagen peptide, other sources of marine collagen, and glycine in treating OA. In the OA rat model, an anterior cruciate ligament transection combined with medial meniscectomy surgery (ACLT + MMx) was used to induce osteoarthritis in rats. Two weeks before surgery, male Sprague-Dawley rats were fed a chow-fat diet. After 6 weeks of treatment with collagen, collagen peptide, and glycine, the results show that they could inhibit the production of proinflammatory cytokines and their derivatives, such as COX-2, MMP-13, and CTX-II levels; therefore, it can attenuate cartilage degradation. Moreover, collagen peptides can promote the synthesis of collagen type II in cartilage. These results demonstrate that collagen and glycine have been shown to have protective properties against OA cartilage degradation. In contrast, collagen peptides have been shown to show cartilage regeneration but less protective properties. Jellyfish collagen peptide at a dose of 5 mg/kg b. w. has the most significant potential for treating OA because it protects and regenerates cartilage in the knee.

Therapeutic Effect of Nile Tilapia Type II Collagen on Rigidity in CD8+ Cells by Alleviating Inflammation and Rheumatoid Arthritis in Rats by Oral Tolerance

Fibrillins are microfibril-associated macro glycoproteins found in connective tissues and structurally related to latent TGF-β-binding proteins (LTBPs). The special cellular immunity and blocking glycoprotein receptors IIb and IIIa of fibrillins are emerging topics in recent years. In this study, Nile Tilapia type IIcollagen (NTCII) was extracted and purified from the skull cartilages by a pepsin-soluble method. Amino acid analysis indicated that NTCII consisted of 315/1000 glycine residues, 72/1000 hydroxyproline residues and 108/1000 proline residues. SDS-PAGE analysis showed that NTCII was composed of three identical 130 kDa α-chains. The results of glycoprotein/carbohydrate assay indicated that the total polysaccharide content of NTCII was 5.6–19.0%. The IR spectrum of NTCII displayed five characteristic peaks of amide I, II, III, A, B. NTCII at 10–100 μg/mL concentration downregulated the content of cytokines in the presence or absence of LPS, especially the secretion of cytokines IL-6, IL-1β and TNF-α. Interestingly, NTCII promoted the secretion of Fas/Apo-1 compared to the control group and 25 μg/mL of NTCII resulted in a higher Fas/Apo-1 secretion level in CD8⁺ T cells. FITC-TCII fluorescence images confirmed that NTCII could bind to the membrane surface of CD8⁺ T cells, leading to the induction of rigidity. NTCII could bind to the membrane surface of CD8⁺ T cells that leads to the induction of rigidity, as evidenced by the FITC-NTCII fluorescence images. The qRT-PCR gene expression analysis of caspase-8 collected with Fas/Apo-1 was upregulated significantly in the 1 and 50 μg/mL NTCII-treated groups compared with the control group. Overall, the results conclude that the rigidity did not lead to an increase in inflammatory factors in CD8⁺ T cells treated with NTCII. The oral administration of NTCII 3 mg/kg dosage caused more prominent repair of damaged ankle cartilage than the 1 mg/kg dosage in Freund’s adjuvant-induced model of arthritis in rats. Therefore, this study disclosed the immunological and anti-arthritic effect of fibrillar collagen, which could be a potential biomaterial for practical applications with lower toxicity.

Nutraceutical Approach to Chronic Osteoarthritis: From Molecular Research to Clinical Evidence

Osteoarthritis (OA) is a degenerative inflammatory condition of the joint cartilage that currently affects approximately 58 million adults in the world. It is characterized by pain, stiffness, and a reduced range of motion with regard to the arthritic joints. These symptoms can cause in the long term a greater risk of overweight/obesity, diabetes mellitus, and falls and fractures. Although the current guidelines for the treatment of OA suggest, as the gold standard for this condition, pharmacological treatment characterized by non-steroidal anti-inflammatory drugs (NSAID), opioids, and cyclooxygenase (COX)-2-specific drugs, a great interest has been applied to nutraceutical supplements, which include a heterogeneous class of molecules with great potential to reduce inflammation, oxidative stress, pain, and joint stiffness and improve cartilage formation. The purpose of this review is to describe the potential application of nutraceuticals in OA, highlighting its molecular mechanisms of actions and data of efficacy and safety (when available).

Comparative study between human mesenchymal stem cells and etanercept as immunomodulatory agents in rat model of rheumatoid arthritis

To compare human adipose tissue mesenchymal stem cells (AT-MSCs) and etanercept as immunomodulatory agents for collagen-induced arthritis (CIA). CIA was induced by rats' immunization with collagen type II (CII) in complete Freund's adjuvant in days 0 and 7. Before the onset of CIA, prevention group received five doses of AT-MSCS intraperitoneally. After establishment of arthritis, rats received either five doses of AT-MSCs or phosphate-buffered saline (PBS) intraperitoneally or six doses of etanercept subcutaneously. Clinical and histopathological evaluation were performed in all groups; serum levels of tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10), and anti-collagen II were assessed by enzyme-linked immunosorbent assay (ELISA). A total percent of autoreactive T and regulatory T (Treg) cells were quantified using spleen immune histochemical analysis. AT-MSCs were able to delay the onset of CIA, suppress the ongoing clinical and histopathological signs, decrease serum levels of TNF-α and anti-collagen type II, and downregulate the autoreactive T cells as etanercept. AT-MSCs were more potent in Treg cells upregulation, producing high serum levels of IL10. AT-MSCs might have a therapeutic effect in CIA via their potency in immune cell education, representing an effective new promising approach in rheumatoid arthritis in human.

Functional Characterization of Undenatured Type II Collagen Supplements: Are They Interchangeable?

Undenatured (native) type II collagen is a dietary supplement ingredient reported to support joint health in healthy individuals by providing relief from symptoms of stiffness and discomfort and improving mobility. This benefit is thought to occur through oral tolerance, a mechanism whereby the immune system distinguishes between innocuous material in the gut and potentially harmful foreign invaders. The presence of antigenic epitopes in undenatured type II collagen, but not in denatured (hydrolyzed) collagen, is thought to be the basis for the therapeutic benefits. The purpose of this study was to investigate the physicochemical and analytical characteristics of type II collagen supplements currently available on the market and to explore whether they might be sufficiently similar in their physical properties to yield similar benefits in promoting joint health. Collagen type II supplement powders (raw material) and capsules (products in the market) were examined for color, particle size, quality profiles, fatty acid profiles, electron microscopy, and were analyzed for amino acid content as well as antigenic potential via an ELISA assay. Powders labeled as undenatured type II collagen were found to have markedly different properties, including the size of collagen fibers as per electron microscopy and antigenic configuration as per the ELISA assay. As significant differences were found between products, it allows consumers and practitioners to not assume that products labeled as undenatured (native) type II collagen are interchangeable.

Undenatured type II collagen prevents and treats osteoarthritis and motor function degradation in T2DM patients and db/db mice

Osteoarthritis (OA) has been scarcely researched among patients with diabetes mellitus. This study aims to confirm the preventive and therapeutic effects of undenatured type II collagen (UC II) on OA in aging db/db mice and in patients with T2DM. Firstly, aging db/db mice were randomly assigned to three groups: the UC II intervention (UC II) group, old model (OM) group and positive control group. Meanwhile db/m mice and young db/db mice were used as the normal control and young control groups, respectively. Secondly, fifty-five T2DM patients diagnosed with knee OA were randomly assigned to two groups: UC-II and placebo control groups. After a three-month intervention in both mice and T2DM patients, the subjects' gait and physical activities were assessed and the serum biomarkers including inflammatory cytokines, oxidative stress factors and matrix metalloproteinases (MMPs) were measured. Compared with the OM group mice, those in the UC II group showed a significantly greater superiority in terms of motor functions including the movement trajectories area (163.25 ± 20.3 vs. 78.52 ± 20.14 cm²), the tremor index (0.42 vs. 1.23), standing time (left hind: 0.089 ± 0.03 vs. 0.136 ± 0.04 s), swing (right front: 0.12 ± 0.02 vs. 0.216 ± 0.02 s), stride length (right hind: 7.2 ± 0.9 vs. 5.7 ± 1.1 cm), step cycle (right hind: 0.252 ± 0.05 vs. 0.478 ± 0.11 s) and cadence (14.12 ± 2.7 vs. 7.35 ± 4.4 steps per s). In addition, the levels of IL-4, IL-10, CTX- II and TGF-β in the UC II group were 1.74, 2.23, 1.67 and 1.84 times higher than those in the OM group, respectively, while the levels of MMP-3 and MMP-13 in the UC II group were half those in the OM group. Correspondingly, UC II intervention significantly decreased the scores of pain, stiffness and physical function (p < 0.05), whereas the 6 MWT and total MET distances in the UC II group increased remarkably (p < 0.05). After a three-month period of intervention, the varus angle significantly decreased from 4.6 ± 2.0° to 3.0 ± 1.4° and the knee flexion range obviously increased from 57.9 ± 14.0° to 66.9 ± 10.4°. Importantly, the declining trend in the levels of hs-CRP and MDA and the incremental trend in the SOD level were consistent in the db/db mice and OA patients following UC II administration.

Effects of Exercise Combined with Undenatured Type II Collagen on Endurance Capacity, Antioxidant Status, Muscle Lipogenic Genes and E3 Ubiquitin Ligases in Rats

The current study aimed to investigate the effect of exercise combined with undenatured type II collagen (UCII) administration on endurance capacity, lipid metabolism, inflammation, and antioxidant status in rats. Twenty-one male Wistar albino rats were divided into three groups as follows: (1) Sedentary control, (2) Exercise (E), (3) Exercise + UCII (4 mg/kg BW/day; E + UCII). The findings showed that the exhaustive running time in the UCII group was significantly prolonged compared to that of the non-supplemented group (p < 0.001). When compared to the control group, total serum cholesterol (TC, p < 0.05) and triglyceride (TG, p < 0.05) levels decreased, while creatinine kinase (CK) levels increased in the E group (p < 0.001). Serum creatinine kinase levels were reduced in the E + UCII group compared to the E group (p < 0.01). Serum lactate, myoglobin (p < 0.01), and osteocalcin levels (p < 0.01) increased significantly in exercised rats compared to sedentary control rats, while serum lactate (p < 0.01) and myoglobin (p < 0.0001) levels decreased in the E + UCII group compared to control. Additionally, UCII supplementation caused significant increases in antioxidant enzyme activities [SOD (p < 0.01) and GSH-Px (p < 0.05)] and decreases in malondialdehyde (MDA) and tumor necrosis factor (TNF-α) levels (p < 0.001). Muscle lipogenic protein (SREBP-1c, ACLY, LXR, and FAS) levels were lower in the E + UCII group than in other groups. In addition, UCII supplementation decreased muscle MAFbx, MuRF-1, myostatin and increased MyoD levels in exercised rats. Moreover, the E + UCII group had lower muscle inflammatory markers [TNF-α (p < 0.0001) and IL-1β (p < 0.01)] than the control group. These results suggest exercise combined with UCII (4 mg/kg BW/day) modulates lipid, muscle, and antioxidant status in rats.

Undenatured Type II Collagen Ameliorates Inflammatory Responses and Articular Cartilage Damage in the Rat Model of Osteoarthritis

Osteoarthritis (OA) is an age-related joint disease that includes gradual disruption of the articular cartilage and the resulting pain. The present study was designed to test the effects of undenatured type II collagen (UC-II®) on joint inflammation in the monoiodoacetate (MIA) OA model. We also investigated possible mechanisms underlying these effects. Female Wistar rats were divided into three groups: (i) Control; (ii) MIA-induced rats treated with vehicle; (iii) MIA-induced rats treated with UC-II (4 mg/kg BW). OA was induced in rats by intra-articular injection of MIA (1 mg) after seven days of UC-II treatment. UC-II reduced MIA-induced Kellgren-Lawrence scoring (53.3%, P < 0.05). The serum levels of inflammatory cytokines [IL-1β (7.8%), IL-6 (18.0%), TNF-α (25.9%), COMP (16.4%), CRP (32.4%)] were reduced in UC-II supplemented group (P < 0.0001). In the articular cartilage, UC-II inhibited the production of PGE2 (19.6%) and the expression of IL-1β, IL-6, TNF-a, COX-2, MCP-1, NF-κB, MMP-3, RANKL (P < 0.001). The COL-1 and OPG levels were increased, and MDA decreased in UC-II supplemented rats (P < 0.001). UC-II could be useful to alleviate joint inflammation and pain in OA joints by reducing the expression of inflammatory mediators.

Toxicological and Anti-Rheumatic Potential of Trachyspermum ammi Derived Biogenic Selenium Nanoparticles in Arthritic Balb/c Mice

Purpose

The existing treatment modalities for rheumatoid arthritis are less effective and safe, therefore it is essential to develop new treatments that particularly target the inflamed joints with decreased off-target side-effects. The current study proposes a nanoparticle-based therapeutic approach to target the anti-oxidant defense system of arthritic Balb/c mice.

Methods

Biogenic selenium nanoparticles (SeNPs) were synthesized by using Trachyspermum ammi seed extract and were evaluated for their toxicological, as well as their therapeutic potential in collagen-induced arthritic mice.

Results

The tested doses of SeNPs had no significant toxic effects on liver, kidney, spleen, and serum biochemical parameters in comparison to healthy mice. The SeNPs treatment reduced the disease severity, as demonstrated by decreased paw edema along with reduced lymphocytic cellular infiltration in the histopathological findings. SeNPs also revealed dose-independent improvement in the redox state of inflamed synovium by significantly improving the activity of antioxidant enzymes in comparison to the arthritic controls.

Conclusion

It is therefore concluded that nano-selenium in combination with TAE extract showed enhanced therapeutic efficacy as compared to their individual effects.

Undenatured Type II Collagen (UC-II) in Joint Health and Disease: A Review on the Current Knowledge of Companion Animals

OA is quite common in companion animals, especially in large breed dogs and horses. Collagen, the most abundant protein of mammals, has specific connective tissue types for skin, bones, reticulate, basal lamina, bones, cell surfaces, while type II collagen (UC-II) forms the main structure of cartilage tissue. Even at the smaller dosages, UC-II has also been reported to be more effective than the glucosamine and chondroitin sulfate supplements, which are the supplements most frequently used in the market. In this review, we summarize the effects of UC-II on joint health and function in health and disease conditions in companion animals.

Immune Tolerance Effect in Mesenteric Lymph Node Lymphocytes of Geniposide on Adjuvant Arthritis Rats

Rheumatoid arthritis (RA) is a systemic, Th1 cytokine-predominant autoimmune disease result in a chronic and inflammatory disorder. Geniposide (GE), an iridoid glycoside compound that is purified from Gardenia jasminoides Ellis, has antiinflammatory and other immunoregulatory effects, but its exact mechanism of actions on RA is unknown. The aim of this study was to elucidate antiinflammation effects of GE on adjuvant arthritis (AA) rats and its possible immune tolerance mechanisms. Male Sprague-Dawley rats were administered with GE (30, 60, and 120 mg/kg) orally from day 17 to 24 after immunization. Lymphocyte proliferation was assessed by MTT. Levels of interleukin-2 (IL-2), IL-4, and transforming growth factor-β1 were tested by ELISA. The expression of β2-AR, GRK2, and β-arrestin-1 and β-arrestin-2 was detected by western blot. Geniposide was found to relieve the secondary hind paw swelling and arthritis scores, along with attenuating histopathologic changes and decreasing IL-2 and increasing IL-4, transforming growth factor-β1 in mesenteric lymph node (MLN) lymphocytes of AA rats. In addition, GE in vivo increased the expression of β2-AR and decreased the expression of GRK2, β-arrestin-1 and β-arrestin-2, and level of cyclic adenosine monophosphate of MLN lymphocytes in AA rats. From these results, we can infer that GE on immune tolerance effects, β2-AR desensitization, and β2-AR-AC-cyclic adenosine monophosphate transmembrane signal transduction of MLN lymphocytes plays crucial roles in antiinflammatory and immunoregulatory pathogeneses of RA. Copyright © 2017 John Wiley & Sons, Ltd.

Dose-response characteristics of Clematis triterpenoid saponins and clematichinenoside AR in rheumatoid arthritis rats by liquid chromatography/mass spectrometry-based serum and urine metabolomics

Clematidis Radix et Rhizoma is a traditional Chinese medicine widely used for treating arthritic disease. Clematis triterpenoid saponins (TS) and clematichinenoside AR (C-AR) have been considered to be responsible for its antiarthritic effects. However, the underling mechanism is still unclear because of their low bioavailability. To address of this issue, metabolomics tools were performed to determine metabolic variations associated with rheumatoid arthritis (RA) and responses to Clematis TS, C-AR and positive drug (Triptolide, TP) treatments. This metabolomics investigation of RA was conducted in collagen-induced arthritis (CIA) rats. Liquid chromatography/mass spectrometry and multivariate statistical tools were used to identify the alteration of serum and urine metabolites associated with RA and responses to drug treatment. As a result, 45 potential metabolites associated with RA were identified. After treatment, a total of 24 biomarkers were regulated to normal like levels. Among these, PC(18:0/20:4), 9,11-octadecadienoic acid, arachidonic acid, 1-methyladenosine, valine, hippuric acid and pantothenic acid etc, were reversed in Clematis TS and C-AR groups. Tetrahydrocortisol was regulated to normal levels in Clematis TS and TP groups, while 3,7,12-trihydroxycholan-24-oic acid was regulated in C-AR and TP groups. Biomarkers like citric acid, p-cresol glucuronide, creatinine, cortolone were reversed in TP group.

β2-adrenoceptor signaling reduction in dendritic cells is involved in the inflammatory response in adjuvant-induced arthritic rats

Rheumatoid arthritis (RA) is characterized by inflammation of the synovium, which leads to the progressive destruction of cartilage and bone. Adrenoreceptor (AR) signaling may play an important role in modulating dendritic cell (DC), which may be involved in the pathogenesis of RA. We examined the effect of the β-AR agonist isoprenaline (ISO) on DC function, the impact of the β₂-AR agonist salbutamol on adjuvant-induced arthritic (AA) rats, and changes in β₂-AR signaling in DCs during the course of AA. ISO inhibited the expression of the surface molecules CD86 and MHC-II, inhibited the stimulation of T lymphocyte proliferation by DC and TNF-α secretion, and promoted DC antigen uptake and IL-10 secretion. The effects of ISO on MHC-II expression, DC stimulation of T lymphocyte proliferation, and DC antigen uptake were mediated by β₂-AR. Treatment with salbutamol ameliorated the severity of AA and histopathology of the joints and inhibited proliferation of thymus lymphocytes and FLS in vivo. β₂-AR signaling was weaker in AA rats compared to the control. Elevated GRK2 and decreased β₂-AR expression in DC cytomembranes were observed in AA and may have decreased the anti-inflammatory effect of β₂-AR signaling. Decreased β₂-AR signaling may be relevant to the exacerbation of arthritis inflammation.

Advancing biomaterials of human origin for tissue engineering

Biomaterials have played an increasingly prominent role in the success of biomedical devices and in the development of tissue engineering, which seeks to unlock the regenerative potential innate to human tissues/organs in a state of deterioration and to restore or reestablish normal bodily function. Advances in our understanding of regenerative biomaterials and their roles in new tissue formation can potentially open a new frontier in the fast-growing field of regenerative medicine. Taking inspiration from the role and multi-component construction of native extracellular matrices (ECMs) for cell accommodation, the synthetic biomaterials produced today routinely incorporate biologically active components to define an artificial in vivo milieu with complex and dynamic interactions that foster and regulate stem cells, similar to the events occurring in a natural cellular microenvironment. The range and degree of biomaterial sophistication have also dramatically increased as more knowledge has accumulated through materials science, matrix biology and tissue engineering. However, achieving clinical translation and commercial success requires regenerative biomaterials to be not only efficacious and safe but also cost-effective and convenient for use and production. Utilizing biomaterials of human origin as building blocks for therapeutic purposes has provided a facilitated approach that closely mimics the critical aspects of natural tissue with regard to its physical and chemical properties for the orchestration of wound healing and tissue regeneration. In addition to directly using tissue transfers and transplants for repair, new applications of human-derived biomaterials are now focusing on the use of naturally occurring biomacromolecules, decellularized ECM scaffolds and autologous preparations rich in growth factors/non-expanded stem cells to either target acceleration/magnification of the body's own repair capacity or use nature's paradigms to create new tissues for restoration. In particular, there is increasing interest in separating ECMs into simplified functional domains and/or biopolymeric assemblies so that these components/constituents can be discretely exploited and manipulated for the production of bioscaffolds and new biomimetic biomaterials. Here, following an overview of tissue auto-/allo-transplantation, we discuss the recent trends and advances as well as the challenges and future directions in the evolution and application of human-derived biomaterials for reconstructive surgery and tissue engineering. In particular, we focus on an exploration of the structural, mechanical, biochemical and biological information present in native human tissue for bioengineering applications and to provide inspiration for the design of future biomaterials.

JAK1-STAT3 blockade by JAK inhibitor SHR0302 attenuates inflammatory responses of adjuvant-induced arthritis rats and decreases Th17 and total B cells

OBJECTIVE

To investigate the effects of JAK inhibitor (SHR0302) on adjuvant-induced arthritis (AA) rats and the partial mechanisms focused on T, B lymphocyte subsets through JAK1-STAT3 pathway, including Th17, Treg, total B cells and memory B cells.

METHODS

Animals were divided randomly into normal control, AA, SHR0302 (0.3,1.0, 3.0mg/kg) and MTX. The effects of SHR0302 on AA rats by evaluating arthritis index, arthritis global assessment and paw swelling degree, histopathology of joint and spleen. We examined the proliferation of T, B and FLS. Th17, Treg, total B and memory B cell proportion was measured by flow cytometry. Cytokines TNF-α, IL-1β, IL-10, IL-17 and antibody IgG1, IgG2a levels in serum were measured by Elisa. The expression of p-JAK1 and p-STAT3 was measured by western blot.

RESULTS

SHR0302 suppressed the severity of AA rats by attenuating the arthritis index, arthritis global assessment and paw swelling degree, and alleviated histopathology of spleen and joint of AA rats. SHR0302 can inhibit the proliferation of T, B and FLS, and down-regulated cytokines TNF-α, IL-1β, IL-17 and antibody IgG1, IgG2a levels, and suppressed the proportion of Th17 and total B, and inhibited JAK1-STAT3 phosphorylation. There was no significant effect on Treg function and memory B cell proportion.

CONCLUSION

SHR0302 may attenuate the severity of AA rats, partially through reducing Th17 function and total B cell proportion by inhibiting JAK1-STAT3 phosphorylation.

Efficacy and tolerability of an undenatured type II collagen supplement in modulating knee osteoarthritis symptoms: a multicenter randomized, double-blind, placebo-controlled study

Background

Undenatured type II collagen (UC-II) is a nutritional supplement derived from chicken sternum cartilage. The purpose of this study was to evaluate the efficacy and tolerability of UC-II for knee osteoarthritis (OA) pain and associated symptoms compared to placebo and to glucosamine hydrochloride plus chondroitin sulfate (GC).

Methods

One hundred ninety one volunteers were randomized into three groups receiving a daily dose of UC-II (40 mg), GC (1500 mg G & 1200 mg C), or placebo for a 180-day period. The primary endpoint was the change in total Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) from baseline through day 180 for the UC-II group versus placebo and GC. Secondary endpoints included the Lequesne Functional Index (LFI), the Visual Analog Scale (VAS) for pain and the WOMAC subscales. Modified intent-to-treat analysis were performed for all endpoints using analysis of covariance and mixed model repeated measures, while incremental area under the curve was calculated by the intent-to-treat method.

Results

At day 180, the UC-II group demonstrated a significant reduction in overall WOMAC score compared to placebo (p = 0.002) and GC (p = 0.04). Supplementation with UC-II also resulted in significant changes for all three WOMAC subscales: pain (p = 0.0003 vs. placebo; p = 0.016 vs. GC); stiffness (p = 0.004 vs. placebo; p = 0.044 vs. GC); physical function (p = 0.007 vs. placebo). Safety outcomes did not differ among the groups.

Conclusion

UC-II improved knee joint symptoms in knee OA subjects and was well-tolerated. Additional studies that elucidate the mechanism for this supplement’s actions are warranted.

Trial registration

CTRI/2013/05/003663; CTRI/2013/02/003348.

Deletion of IFT20 in early stage T lymphocyte differentiation inhibits the development of collagen-induced arthritis

IFT20 is the smallest member of the intraflagellar transport protein (IFT) complex B. It is involved in cilia formation. Studies of IFT20 have been confined to ciliated cells. Recently, IFT20 was found to be also expressed in non-ciliated T cells and have functions in immune synapse formation and signaling in vitro. However, how IFT20 regulates T-cell development and activation in vivo is still unknown. We deleted the IFT20 gene in early and later stages of T-cell development by crossing IFT20(flox/flox) (IFT20(f/f) ) mice with Lck-Cre and CD4-Cre transgenic mice, and investigated the role of IFT20 in T-cell maturation and in the development of T cell-mediated collagen-induced arthritis (CIA). We found that both Lck-Cre/IFT20(f/f) and CD4-Cre/IFT20(f/f) mice were indistinguishable from their wild-type littermates in body size, as well as in the morphology and weight of the spleen and thymus. However, the number of CD4- and CD8-positive cells was significantly lower in thymus and spleen in Lck-Cre/IFT20(f/f) mice. Meanwhile, the incidence and severity of CIA symptoms were significantly decreased, and inflammation in the paw was significantly inhibited in Lck-Cre/IFT20(f/f) mice compared to Lck-Cre/IFT20(+/+) littermates. Deletion IFT20 in more mature T cells of CD4-Cre/IFT20(f/f) mice had only mild effects on the development of T cells and CIA. The expression of IL-1β, IL-6 and TGF-β1 were significantly downregulated in the paw of Lck-Cre/IFT20(f/f) mice, but just slight decreased in CD4-Cre/IFT20(f/f) mice. These results demonstrate that deletion of IFT20 in the early stage of T-cell development inhibited CIA development through regulating T-cell development and the expression of critical cytokines.

Metabolomics analysis of collagen-induced arthritis in rats and interventional effects of oral tolerance

A serum metabolomics method based on rapid resolution liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (RRLC-Q-TOF-MS) was performed for a holistic evaluation of the metabolic changes of collagen-induced arthritis (CIA) in rats and to assess the interventional effects of type II collagen (CII) in this model. Partial least-squares-discriminant analysis (PLS-DA) was employed to study the metabolic profiling of CIA rats and control rats. Ten metabolites, namely, 12(S)-HHTrE, 12(S)-HEPE, PGE2, TXB2, 12(S)-HETE, LysoPE(16:0), PE(O-18:0/0:0), Lyso-PE(18:2), Lyso-PE(20:4), and Lyso-PC(22:5) were identified as differential metabolites associated with the pathogenesis of CIA. These results suggested that dysregulation of the arachidonic acid (AA) and phospholipid metabolic networks is involved in the pathomechanism of CIA. Differential metabolomics and histopathological analyses demonstrated that CII inhibits the progress of arthritis. Furthermore, the therapeutic effects of CII on CIA may involve regulation of the disordered AA and phospholipid metabolic networks. This metabolomics study provides new insights into the pathogenesis of arthritis and, furthermore, indicates the potential mechanism underlying the significantly increased prevalence of metabolic syndrome, defined as a clustering of cardiovascular disease (CVD) risk factors, in arthritis patients.

Ginsenoside compound K suppresses the abnormal activation of T lymphocytes in mice with collagen-induced arthritis

AIM

To investigate the anti-arthritis and immunomodulatory activities of ginsenoside compound K (C-K) in mice with collagen-induced arthritis (CIA).

METHODS

DBA/1 mice with CIA were treated with C-K (28, 56 or 112 mg·kg(-1)·d(-1), ig) or the positive control methotrexate (2 mg/kg, ig, every 3 d) for 34 d. Splenic T and B lymphocytes were positively isolated using anti-CD3-coated magnetic beads or a pan B cell isolation kit. T lymphocyte subsets, and CD28, T cell receptor (TCR), cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) and programmed death-1 (PD-1) expression in purified splenic T lymphocytes were analyzed using flow cytometry, Western blotting and laser confocal microscopy.

RESULTS

C-K treatment significantly ameliorated the pathologic manifestations of CIA mice, remarkably inhibited T lymphocyte proliferation, and marginally inhibited the proliferation of B lymphocytes. C-K treatment significantly suppressed TNF-α and anti-CII antibody levels, and increased IFN-γ level in the joints of CIA mice, but did not alter IL-4 production. Treatment of CIA mice with C-K significantly decreased the percentages of activated T cells, co-stimulatory molecule-expressing T cells and effector memory T cells, and increased the frequencies of naive T cells and regulatory T cells. Furthermore, C-K treatment significantly decreased the expression of CD28 and TCR, whereas it increased the expression of CTLA-4 and PD-1 on T lymphocytes of CIA mice. Methotrexate treatment exerted comparable effects in all these experiments.

CONCLUSION

C-K suppresses the progression of CIA through regulating TCR, CD28, CTLA-4 and PD-1 expression, thus inhibiting the abnormal activation and differentiation of T lymphocytes.

Undenatured type II collagen (UC-II®) for joint support: a randomized, double-blind, placebo-controlled study in healthy volunteers

BACKGROUND

UC-II contains a patented form of undenatured type II collagen derived from chicken sternum. Previous preclinical and clinical studies support the safety and efficacy of UC-II in modulating joint discomfort in osteoarthritis and rheumatoid arthritis. The purpose of this study was to assess the efficacy and tolerability of UC-II in moderating joint function and joint pain due to strenuous exercise in healthy subjects.

METHODS

This randomized, double-blind, placebo-controlled study was conducted in healthy subjects who had no prior history of arthritic disease or joint pain at rest but experienced joint discomfort with physical activity. Fifty-five subjects who reported knee pain after participating in a standardized stepmill performance test were randomized to receive placebo (n = 28) or the UC-II (40 mg daily, n = 27) product for 120 days. Joint function was assessed by changes in degree of knee flexion and knee extension as well as measuring the time to experiencing and recovering from joint pain following strenuous stepmill exertion.

RESULTS

After 120 days of supplementation, subjects in the UC-II group exhibited a statistically significant improvement in average knee extension compared to placebo (81.0 ± 1.3º vs 74.0 ± 2.2º; p = 0.011) and to baseline (81.0 ± 1.3º vs 73.2 ± 1.9º; p = 0.002). The UC-II cohort also demonstrated a statistically significant change in average knee extension at day 90 (78.8 ± 1.9º vs 73.2 ± 1.9º; p = 0.045) versus baseline. No significant change in knee extension was observed in the placebo group at any time. It was also noted that the UC-II group exercised longer before experiencing any initial joint discomfort at day 120 (2.8 ± 0.5 min, p = 0.019), compared to baseline (1.4 ± 0.2 min). By contrast, no significant changes were seen in the placebo group. No product related adverse events were observed during the study. At study conclusion, five individuals in the UC-II cohort reported no pain during or after the stepmill protocol (p = 0.031, within visit) as compared to one subject in the placebo group.

CONCLUSIONS

Daily supplementation with 40 mg of UC-II was well tolerated and led to improved knee joint extension in healthy subjects. UC-II also demonstrated the potential to lengthen the period of pain free strenuous exertion and alleviate the joint pain that occasionally arises from such activities.

Therapeutic effects of TACI-Ig on collagen-induced arthritis by regulating T and B lymphocytes function in DBA/1 mice

To investigate the abnormal function of T and B lymphocytes involved in collagen-induced arthritis in DBA/1 mice and the regulation role of TACI-Ig on T and B lymphocytes, collagen-induced arthritis models were established in DBA/1 mice. Mice were divided randomly into eight groups, including normal, collagen-induced arthritis model, TACI-Ig (0.350, 1.105, 3.333, 10, and 30 mg/kg) and IgG-Fc (10mg/kg) treated groups. The effect of TACI-Ig on collagen-induced arthritis was evaluated by arthritis scores, joints and spleens histopathology, paws radiology, and indices of thymus and spleen. T and B lymphocyte proliferations were assayed by [(3)H]-TdR method. B lymphocyte stimulator and prostaglandin E(2) in serum were assayed by enzyme linked immunosorbent assay. The subsets of T and B lymphocytes were assayed by flow cytometry. Results showed that the onset of paw-swelling was on day 31 after immunization. The peak of inflammation appeared on day 42 and then declined after day 63. Compared with normal mice, collagen-induced arthritis mice have increased arthritis scores, spleen and thymus indices, radiograph scores of joints, and pathology scores of joints and spleens. TACI-Ig could ameliorate these changes and reduce the increased serum level of B lymphocyte stimulator and prostaglandin E(2). Further studies showed that TACI-Ig inhibited T and B lymphocyte proliferation response, and inhibited differentiation and activity of T and B lymphocytes in collagen-induced arthritis mice. In conclusion, TACI-Ig has a good therapeutic action on collagen-induced arthritis mice, which might be related to the regulation of TACI-Ig on inflammation mediators and abnormal function of T and B lymphocytes.

Therapeutic effects of TACI-Ig on rat with adjuvant arthritis

Transmembrane activator and calcium modulator and cyclophilin ligand interactor-immunoglobulin (TACI-Ig) is a human fusion protein that binds and neutralizes both B lymphocyte stimulator (BLyS), a cytokine shown to be a key regulator of B cell maturation, proliferation and survival, and a proliferation-inducing ligand (APRIL). Rat adjuvant arthritis (AA) is an experimental animal model of rheumatoid arthritis (RA), which is mainly dependent on T cells and neutrophil-mediated cytokine production. The purpose of the present study was to investigate the effects of TACI-Ig on rat AA. Rat AA was induced by intradermal injection of 0·1 ml complete Freund's adjuvant (CFA). TACI-Ig (0·7, 2·1 and 6·3 mg/kg), recombinant human tumour necrosis factor-α receptor (rhTNFR) : Fc (2·8 mg/kg) and IgG-Fc (6·3 mg/kg) were administered subcutaneously every other day from days 16 to 34 after immunization. Arthritis was evaluated by arthritis global assessment and swollen joint count (SJC). The ankle joint and spleen were harvested for histopathological examination. Spleen index and thymus index were calculated. The levels of BLyS, interleukin (IL)-17, interferon (IFN)-γ, IgG1, IgG2a and IgM in AA rat spleen were measured by enzyme-linked immunosorbent assay. Administration of TACI-Ig significantly reduced the arthritis global assessment and SJC, decreased spleen index and ameliorated histopathological manifestations of rat AA. Suppressing the levels of BLyS, IL-17, IFN-γ and Ig in AA rat spleen were observed after administration of TACI-Ig. These results showed that TACI-Ig significantly inhibited the degree of rat AA, and the inhibitory effects might be associated with its ability to reduce BLyS, proinflammatory cytokines and Ig levels in spleen.

2,3,7,8-Tetrachlorodibenzo-p-dioxin impairs stable establishment of oral tolerance in mice

The toxic environmental pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a potent immunomodulatory chemical. TCDD activates the aryl hydrocarbon receptor (AhR) and suppresses peripheral humoral and cellular adaptive immune responses. Though the major route of uptake is via food, little is known until now on the immunotoxic effects of TCDD on the gut-associated lymphoid tissue. We show here that AhR is strongly expressed along the small intestine, especially in intestinal epithelial cells (IEC). The AhR marker gene cyp1a1 is induced in IEC by oral TCDD exposure. We asked how TCDD affects oral tolerance, a unique function of mucosal immunity. C57BL/6 mice were injected with 10 μg/kg body weight TCDD and fed with ovalbumin (OVA) in a high-dose tolerization protocol. Mice were immunized and boosted with OVA on days 12, 23, and 55 after tolerization. Five of 14, 6 of 15, and 13 of 14 TCDD-treated mice generated OVA-specific immunoglobulin (Ig)G1 antibodies after the first, second, and third immunization with OVA, respectively. Only one mouse harbored anti-OVA IgG1 antibodies in the control group even after the third immunization with OVA. OVA-specific IgA in fecal samples of tolerized and TCDD-exposed mice could be detected at the levels of nontolerized mice, whereas completely absent in tolerant control mice. Correlated to this, we found in TCDD-treated mice an increase in interleukin-6 producing CD103+ dendritic cells (DC) present in the gut-draining mesenteric lymph nodes (MLN) and a small increase in the frequency of Th17 cells. Neither the frequencies nor the absolute numbers of immune cells in the lamina propria (LP) or in intraepithelial lymphocytes were changed by TCDD treatment. Our data not only have implications for food allergies in settings of environmental exposure but also raise concerns regarding the harmlessness of overdosing potential AhR agonist in food, which needs to be studied further.

A multicenter, double-blind, randomized, controlled phase III clinical trial of chicken type II collagen in rheumatoid arthritis

Introduction

Chicken type II collagen (CCII) is a protein extracted from the cartilage of chicken breast and exhibits intriguing possibilities for the treatment of autoimmune diseases by inducing oral tolerance. A 24-week, double-blind, double-dummy, randomized, methotrexate (MTX)-controlled study was conducted to evaluate the efficacy and safety of CCII in the treatment of rheumatoid arthritis (RA).

Methods

Five hundred three RA patients were included in the study. Patients received either 0.1 mg daily of CCII (n = 326) or 10 mg once a week of MTX (n = 177) for 24 weeks. Each patient was evaluated for pain, morning stiffness, tender joint count, swollen joint count, health assessment questionnaire (HAQ), assessments by investigator and patient, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) by using the standard tools at baseline (week 0) and at weeks 12 and 24. Additionally, rheumatoid factor (RF) was evaluated at weeks 0 and 24. Measurement of a battery of biochemical parameters in serum, hematological parameters, and urine analysis was performed to evaluate the safety of CCII.

Results

Four hundred fifty-four patients (94.43%) completed the 24-week follow-up. In both groups, there were decreases in pain, morning stiffness, tender joint count, swollen joint count, HAQ, and assessments by investigator and patient, and all differences were statistically significant. In the MTX group, ESR and CRP decreased. RF did not change in either group. At 24 weeks, 41.55% of patients in the CCII group and 57.86% in the MTX group met the American College of Rheumatology 20% improvement criteria (ACR-20) and 16.89% and 30.82%, respectively, met the ACR 50% improvement criteria (ACR-50). Both response rates for ACR-20 and ACR-50 in the CCII group were lower than those of the MTX group, and this difference was statistically significant (P < 0.05). The DAS28 (disease activity score using 28 joint counts) values of the two treatment groups were calculated, and there was a statistically significant difference between the two treatment groups (P < 0.05). Gastrointestinal complaints were common in both groups, but there were fewer and milder side effects in the CCII group than in the MTX group. The incidence of adverse events between the two groups was statistically significant (P < 0.05).

Conclusions

CCII is effective in the treatment of RA and is safe for human consumption. CCII exerts its beneficial effects by controlling inflammatory responses through inducing oral tolerance in RA patients.

Trials Registration

Clinical trial registration number: ChiCTR-TRC-00000093.