The Preventive Effects of Greenshell Mussel (Perna canaliculus) on Early-Stage Metabolic Osteoarthritis in Rats with Diet-Induced Obesity

Medical treatment of osteoarthritis: botanical pharmacologic aspect

Osteoarthritis (OA) is the most common form of arthritis, and its prevalence is expected to further increase as our society ages. Despite many approaches to cure OA, no drugs are currently proven to modulate the progression of OA. Nowadays, new OA treatment options are holistically developed and one of the approaches of treatment option is botanical drugs. Some botanical drugs for OA have shown both therapeutic effect comparable to refined drugs in small studies and fewer side effects. Hence, there are various health functional foods which are known to relieve symptoms of OA. However, since there are many botanical products, clinicians are not familiar to the efficacy of each botanical product, making it challenging to use them appropriately in clinical practice. Here, we summarize the botanical products available for treating OA, including prescription botanical drugs and health functional foods available in Korea. Further studies and the purification of effective molecules from botanical products will be necessary in future.

Effect of Traditional Chinese Non-Pharmacological Therapies on Knee Osteoarthritis: A Narrative Review of Clinical Application and Mechanism

Knee osteoarthritis (KOA) stands as a degenerative ailment with a substantial and escalating prevalence. The practice of traditional Chinese non-pharmacological therapy has become a prevalent complementary and adjunctive approach. A mounting body of evidence suggests its efficacy in addressing KOA. Recent investigations have delved into its underlying mechanism, yielding some headway. Consequently, this comprehensive analysis seeks to encapsulate the clinical application and molecular mechanism of traditional Chinese non-pharmacological therapy in KOA treatment. The review reveals that various therapies, such as acupuncture, electroacupuncture, warm needle acupuncture, tuina, and acupotomy, primarily target localized knee components like cartilage, subchondral bone, and synovium. Moreover, their impact extends to the central nervous system and intestinal flora. More perfect experimental design and more comprehensive research remain a promising avenue in the future.

Obesity, Metabolic Syndrome, and Osteoarthritis-An Updated Review

PURPOSE OF REVIEW

Metabolic syndrome (MetS), also called the 'deadly quartet' comprising obesity, diabetes, dyslipidemia, and hypertension, has been ascertained to have a causal role in the pathogenesis of osteoarthritis (OA). This review is aimed at discussing the current knowledge on the contribution of metabolic syndrome and its various components to OA pathogenesis and progression.

RECENT FINDINGS

Lately, an increased association identified between the various components of metabolic syndrome (obesity, diabetes, dyslipidemia, and hypertension) with OA has led to the identification of the 'metabolic phenotype' of OA. These metabolic perturbations alongside low-grade systemic inflammation have been identified to inflict detrimental effects upon multiple tissues of the joint including cartilage, bone, and synovium leading to complete joint failure in OA. Recent epidemiological and clinical findings affirm that adipokines significantly contribute to inflammation, tissue degradation, and OA pathogenesis mediated through multiple signaling pathways. OA is no longer perceived as just a 'wear and tear' disease and the involvement of the metabolic components in OA pathogenesis adds up to the complexity of the disease. Given the global surge in obesity and its allied metabolic perturbations, this review aims to throw light on the current knowledge on the pathophysiology of MetS-associated OA and the need to address MetS in the context of metabolic OA management. Better regulation of the constituent factors of MetS could be profitable in preventing MetS-associated OA. The identification of key roles for several metabolic regulators in OA pathogenesis has also opened up newer avenues in the recognition and development of novel therapeutic agents.

Purification and Molecular Docking Study on the Angiotensin I-Converting Enzyme (ACE)-Inhibitory Peptide Isolated from Hydrolysates of the Deep-Sea Mussel Gigantidas vrijenhoeki

The objective of this study was to prepare an angiotensin I-converting enzyme (ACE)-inhibitory peptide from the hydrothermal vent mussel, Gigantidas vrijenhoeki. The G. vrijenhoeki protein was hydrolyzed by various hydrolytic enzymes. The peptic hydrolysate exhibited the highest ACE-inhibitory activity and was fractionated into four molecular weight ranges by ultrafiltration. The <1 kDa fraction exhibited the highest ACE inhibitory activity and was found to have 11 peptide sequences. Among the analyzed peptides, KLLWNGKM exhibited stronger ACE inhibitory activity and an IC50 value of 0.007 μM. To investigate the ACE-inhibitory activity of the analyzed peptides, a molecular docking study was performed. KLLWNGKM exhibited the highest binding energy (-1317.01 kcal/mol), which was mainly attributed to the formation of hydrogen bonds with the ACE active pockets, zinc-binding motif, and zinc ion. These results indicate that G. vrijenhoeki-derived peptides can serve as nutritional and pharmacological candidates for controlling blood pressure.

Effect of green-lipped mussel (Perna canaliculus) supplementation on faecal microbiota, body composition and iron status markers in overweight and obese postmenopausal women: a randomised, double-blind, placebo-controlled trial

The present study aimed to determine the effect of whole meat GSM powder on gut microbiota abundance, body composition and iron status markers in healthy overweight or obese postmenopausal women. This was a 3-months trial involving forty-nine healthy postmenopausal women with body mass index (BMI) between 25 and 35 kg/m² who were randomly assigned to receive 3 g/d of either GSM powder (n 25) or placebo (n 24). The gut microbe abundance, serum iron status markers and body composition were measured at the baseline and the end of the study. The between-group comparison at the baseline showed a lower abundance of Bacteroides and Clostridium XIVa in the GSM group compared with the placebo (P = 0⋅04). At the baseline, the body fat (BF)% and gynoid fat% were higher in the GSM group compared with the placebo (P < 0⋅05). No significant changes were found in any of the outcome measures, except for ferritin levels that showed a significant reduction over time (time effect P = 0⋅01). Some trend was observed in bacteria including Bacteroides and Bifidobacterium which tended to increase in the GSM group while their abundance decreased or remained at their baseline level in the control group. Supplementation with GSM powder did not result in any significant changes in gut microbe abundance, body composition and iron markers compared with placebo. However, some commensal bacteria such as Bacteroides and Bifidobacteria tended to increase following supplementation with GSM powder. Overall, these findings can expand the knowledge surrounding the effects of whole GSM powder on these outcome measures in healthy postmenopausal women.

Effects of Greenshell™ mussel intervention on biomarkers of cartilage metabolism, inflammatory markers and joint symptoms in overweight/obese postmenopausal women: A randomized, double-blind, and placebo-controlled trial

Objective

To investigate the effect of whole greenshell mussel (GSM) powder on biomarkers of cartilage metabolism, inflammatory cytokines, and joint symptoms in postmenopausal women with overweight/obesity and joint discomfort.

Design

Fifty-five postmenopausal women with overweight/obesity were randomly assigned to receive 3 g/day whole GSM powder or placebo for 12 weeks. Cartilage turnover biomarkers urinary C-telopeptide of type II collagen (CTX-II) and serum cartilage oligomeric matrix protein (COMP) were measured at baseline, week 6 and 12. Plasma cytokines were measured at baseline and week 12. Joint pain and knee-related problems were assessed at baseline and week 12 using a 100 mm Visual Analogue Scale (VAS) and the Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire, respectively.

Results

Forty-nine participants completed the study (GSM n = 25, placebo n = 24). After 12 weeks, urinary CTX-II showed no significant change over time or between the groups (interaction effect P = 0.1). However, in women with symptomatic knees, a significant difference was noted between the group (treatment effect P = 0.04), as it was lower in the GSM group compared to placebo group at week 6 (P = 0.04) and week 12 (P = 0.03). Serum COMP and plasma cytokines were not affected. GSM supplementation showed greater reduction in the VAS pain score than placebo (-13.2 ± 20.3 vs. -2.9 ± 15.9; P = 0.04). No significant change in KOOS domains between the two groups was observed.

Conclusion

Oral supplementation of whole GSM powder at 3 g/day may slow down the degradation of type II collagen in postmenopausal women with symptomatic knees. GSM treatment conferred clinical benefit on overall joint pain. No significant effect was noted for inflammatory cytokines, suggesting that GSM may act within the joint microenvironment rather than at the systemic level.

Clinical trial registration

[www.australianclinicaltrials.gov.au/clinical-trialregistries], identifier [ACTRN12620000413921p].

Mass Spectrometry-Based Metabolomic and Lipidomic Analysis of the Effect of High Fat/High Sugar Diet and GreenshellTM Mussel Feeding on Plasma of Ovariectomized Rats

This study aimed to examine the changes in lipid and metabolite profiles of ovariectomized (OVX) rats with diet-induced metabolic syndrome-associated osteoarthritis (MetOA) after supplementation with greenshell mussel (GSM) using an untargeted liquid chromatography-mass spectrometry (LC-MS) metabolomics approach. Ninety-six rats were fed with one of four diets: control, control supplemented with GSM + GSM, high fat/high sugar (HFHS), or high fat/high sugar enriched with GSM (HFHS + GSM). After 8 weeks on experimental diets, half of the rats in each group underwent OVX and the other half were sham operated. After being fed for an additional 28 weeks, blood samples were collected for the metabolomics analysis. Lipid and polar metabolites were extracted from plasma and analysed by LC-MS. We identified 29 lipid species from four lipid subclasses (phosphatidylcholine, lysophosphatidylcholine, diacylglycerol, and triacylglycerol) and a set of eight metabolites involved in amino acid metabolism (serine, threonine, lysine, valine, histidine, pipecolic acid, 3-methylcytidine, and cholic acid) as potential biomarkers for the effect of HFHS diet and GSM supplementation. GSM incorporation more specifically in the control diet generated significant alterations in the levels of several lipids and metabolites. Further studies are required to validate these findings that identify potential biomarkers to follow OA progression and to monitor the impact of GSM supplementation.

Non-polar lipid from greenshell mussel (Perna canaliculus) inhibits osteoclast differentiation

The osteoclast-dependent bone resorption process is a crucial part of the bone regulatory system. The excessive function of osteoclasts can cause diseases of bone, joint, and other tissues such as osteoporosis and osteoarthritis. Greenshell mussel oil (GSM), a good source of long chain omega-3 polyunsaturated fatty acids (LCn-3PUFAs), was fractionated into total lipid, polar lipid, and non-polar lipid components and their anti-osteoclastogenic activity tested in RAW 264.7 cell cultures. Osteoclast differentiation process was achieved after 5 days of incubation with RANKL in 24-well culture plates. Introducing the non-polar lipid fraction into the culture caused a lack of cell differentiation, and a reduction in tartrate-resistant acid phosphatase (TRAP) activity and TRAP cell numbers in a dose-dependent manner (50% reduction at the concentration of 20 μg/mL, p < 0.001). Moreover, actin ring formation was significantly diminished by non-polar lipids at 10-20 μg/mL. The bone digestive enzymes released by osteoclasts into the pit formation were also compromised by downregulating gene expression of cathepsin K, carbonic anhydrase II (CA II), matrix metalloproteinase 9 (MMP-9), and nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1). This study revealed that the non-polar lipid fraction of GSM oil contains bioactive substances which possess potent anti-osteoclastogenic activity.

Green-lipped (greenshell™) mussel (Perna canaliculus) extract supplementation in treatment of osteoarthritis: a systematic review

OBJECTIVES

Intervention studies using New Zealand green-lipped or greenshell™ mussel (GSM) (Perna canaliculus) extract in osteoarthritis (OA) patients have shown effective pain relief. This systematic review summarises the efficacy of GSM extracts in the treatment of OA.

METHODS

A literature search of the three databases EMBASE, MEDLINE, and Scopus was performed to identify relevant articles published up to March 2020. Inclusion criteria were clinical trials published in English measuring the effect of supplementation of whole or a lipid extract from GSM on pain and mobility outcomes in OA patients.

RESULTS

A total of nine clinical trials were included in systematic review, from which five studies were considered appropriate for inclusion in a forest plot. Pooled results showed that GSM extracts (lipid extract or whole powder) provide moderate and clinically significant treatment effects on a visual analogue scale (VAS) pain score (effect size: - 0.46; 95% CI - 0.82 to - 0.10; p = 0.01). The whole GSM extract improved gastrointestinal symptoms in OA patients taking anti-inflammatory medications. The GSM extract was considered to be generally well tolerated in most of the studies.

CONCLUSION

The overall analysis showed that GSM provided moderate and clinically meaningful treatment effects on OA pain. However, the current evidence is limited by the number and quality of studies, and further larger and high-quality studies are needed to confirm the effectiveness and to identify the optimal GSM format. Nevertheless, it is worth considering using GSM extracts especially for patients seeking alternative pain relief treatments with fewer side effects compared to conventional treatment.

Effect of GreenshellTM mussel on osteoarthritis biomarkers and inflammation in healthy postmenopausal women: a study protocol for a randomized double-blind placebo-controlled trial

BACKGROUND

New Zealand Greenshell™ mussels (GSM; Perna canaliculus) have recently been shown to decrease cartilage degradation in a rat model of induced metabolic osteoarthritis (MetOA). However, this effect has not been investigated in human subjects. This study aims to determine the effect of GSM powder on biomarkers of cartilage metabolism, bone resorption, and inflammation in New Zealand healthy overweight/obese postmenopausal women who are at early stage or at high risk of OA.

METHOD

Fifty overweight or obese (BMI 25-35 kg/m²) postmenopausal women (aged 55-75 years) will be recruited by advertisement. Participants will be randomized based on a double-blind randomization schedule and stratified randomization based on BMI and age distribution. The participant will be assigned with a 1:1 allocation ratio to receive 3 g/d whole meat GSM powder or placebo (sunflower seed protein) for 12 weeks. Data on socio-demographics, physical activity, and dietary intake will be collected for each subject. Cartilage turnover biomarkers [(C-telopeptide of type II collagen (CTX-II), C-propeptide of type II procollagen (CPII), Cartilage oligomeric matrix protein (COMP)], and bone resorption marker (CTX-I) will be measured in blood and urine samples. Inflammatory status (hs-CRP and cytokine panel) will be assessed and iron status will be measured. Body composition including fat mass (FM), lean mass (LM), and fat percentage will be measured using dual-energy X-ray absorptiometry (DXA). Joint pain and knee function will be assessed using a 100-mm visual analog scale (VAS) and the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire, respectively.

DISCUSSION

This trial will be the first to explore the effects of whole meat GSM powder on cartilage turnover, bone resorption, and inflammation biomarkers in overweight/obese postmenopausal women. The results from this trial will provide evidence on the efficacy of GSM in the prevention of OA.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12620000413921p . Registration on 27 March 2020.

Antioxidant and antithrombotic effects of green mussels (Perna canaliculus) in rats

In the past decade, the use of marine mussels as seafood is being more popular. They considered being a rich source of various nutritional bioactive compounds that aroused the scientific community's interest. This study investigated the antioxidant and the antithrombotic consequences on Sprague-Dawley male rats after adding dried New Zealand mussel Perna canaliculus in their diet. The biochemical, hematological and histopathological changes were also observed. Forty rats were divided into four groups according to the amount of dried mussels in their diet, in addition to a control group that consumed a basal diet only. Group 1 consumed 25% dried mussels in its basal diet; Group 2 consumed 35% dried mussels in its basal diet, and Group 3 was consumed 45% dried mussels in its basal diet. The biochemical parameters showed improvements in liver function. Interestingly, the lipid profile decreased, especially the low-density lipoprotein cholesterol (LDL-C) levels which were reduced significantly in Group 3 (p < .01). These observations were accompanied by a decrease in iron levels significantly as the amount of dried mussels increased (p < .01). Furthermore, the noticed changes in the hematological profile prove that there is an increase in antithrombotic activity. Dried mussels had potent antioxidant effects in the liver as shown by increased lipid peroxide (p < .05), reduced glutathione (p < .05), and glutathione peroxidase (GSH-Px; p < .05). Additionally, antioxidant activity in the kidney was shown to increase through GSH-Px activity (p < .01). In conclusion, these results indicate that consuming dried mussels resulted in improved biochemical and antioxidants activities and could be used as an antithrombotic agent.

The Anti-Inflammatory and the Antinociceptive Effects of Mixed Agrimonia pilosa Ledeb. and Salvia miltiorrhiza Bunge Extract

Arthritis is a common condition that causes pain and inflammation in a joint. Previously, we reported that the mixture extract (ME) from Agrimonia pilosa Ledeb. (AP) and Salvia miltiorrhiza Bunge (SM) could ameliorate gout arthritis. In the present study, we aimed to investigate the potential anti-inflammatory and antinociceptive effects of ME and characterize the mechanism. We compared the anti-inflammatory and antinociceptive effects of a positive control, Perna canaliculus powder (PC). The results showed that one-off and one-week treatment of ME reduced the pain threshold in a dose-dependent manner (from 10 to 100 mg/kg) in the mono-iodoacetate (MIA)-induced osteoarthritis (OA) model. ME also reduced the plasma TNF-α, IL-6, and CRP levels. In LPS-stimulated RAW 264.7 cells, ME inhibited the release of NO, PGE₂, LTB₄, and IL-6, increased the phosphorylation of PPAR-γ protein, and downregulated TNF-α and MAPKs proteins expression in a concentration-dependent (from 1 to 100 µg/mL) manner. Furthermore, ME ameliorated the progression of ear edema in mice. In most of the experiments, ME-induced effects were almost equal to, or were higher than, PC-induced effects. Conclusions: The data presented here suggest that ME shows anti-inflammatory and antinociceptive activities, indicating ME may be a potential therapeutic for arthritis treatment.

Bioavailability of Orally Administered Active Lipid Compounds from four Different Greenshell™ Mussel Formats

Greenshell™ mussel (GSM, Perna canaliculus) is New Zealand's most important aquaculture species. They are a good source of long chain-polyunsaturated fatty acids (n-3 LC PUFA). Beyond a traditional food product, GSMs are also sold as mussel powders and oil extract formats in the nutraceutical markets. In this study, a four-sequence, single dose, randomized crossover human trial with eight evaluable healthy male participants was undertaken to determine the bioavailability of the n-3 LC PUFA in four different GSM formats (oil, powder, food ingredient and half-shell unprocessed whole mussel) by measuring area under the curve (AUC) and maximal concentration (C_Max). Blood samples were collected at baseline and up to 48 h after initiation of product consumption in each administration period. There were minor differences between the bioavailability of FA (fatty acid) between the different GSM formats. Eicosapentaenoic acid (EPA) peak concentrations and plasma exposures were significantly lower with GSM oil compared to GSM half-shell and GSM powder formats, which resulted in AUC_0-48 for the intake of GSM half-shell mussel and GSM powder being significantly higher than that for GSM oil (p = 0.013, f= 4.84). This equated to a 20.6% and 24.3% increase in the amount of EPA present in the plasma after consumption of half-shell mussels and mussel powder respectively compared to GSM oil. GSM oil produced the shortest median time to maximal plasma n-3 LC PUFA concentration of all evaluated products demonstrated by a shorter maximum measured plasma concentration (T_Max = 5 h). Docosahexaenoic acid (DHA) and n-3 LC PUFA plasma exposure parameters were statistically comparable across the four GSM products evaluated.

Effects of Greenshell Mussel (Perna canaliculus) Intake on Pathological Markers of Multiple Phenotypes of Osteoarthritis in Rats

The prevalence of metabolic osteoarthritis has been increasing worldwide, particularly among women. The aim of this study was to investigate the effects of the New Zealand greenshell mussel (Perna canaliculus; GSM) on osteoarthritis (OA) prevention in a rat model. One-hundred-and-eight female rats aged 12 weeks were divided into four test groups, containing 24 rats each, plus an additional control group. Each test group received one of the four experimental diets: normal control diet (ND), normal control diet supplemented with GSM (ND + GSM), high fat/high sugar diet (HFHS), or high fat/high sugar diet supplemented GSM (HFHS + GSM), for 36 weeks (end of the study). After 8 weeks on experimental diets, half of each group was subjected to ovariectomy (OVX) and the remaining half received a sham operation (ovaries left intact). The study evaluated body composition, bone mass, plasma cytokines, adipokines, HbA1c, CTX-II, and knee joint’s histopathology. HFHS diet and OVX significantly induced body weight gain and leptin production. OVX rats lost bone mineral density but increased adiponectin, HbA1C, and MCP-1. The OVX rats fed HFHS showed the highest Mankin scores. Importantly, inclusion of GSM reduced these pathological features. In conclusion, GSM might be beneficial in halting the progression of OA.

An update on the association between metabolic syndrome and osteoarthritis and on the potential role of leptin in osteoarthritis

Metabolic syndrome (MetS) has been associated with osteoarthritis (OA). Leptin, which is one of the markers of MetS, has been associated with OA pathophysiology. This study aimed to provide an update on the association between MetS and OA and on the potential role of leptin in OA. In this review, we summarized the current knowledge of the association between MetS and OA and updated the evidence on the potential role of leptin in OA. Clinical studies have investigated the epidemiologic association between MetS or its components and OA. Results suggested strong epidemiologic associations between MetS and OA, especially in the Asian population. Animal studies also indicated that metabolic dysregulation may lead to OA pathogenesis. The systemic role of MetS in OA pathophysiology is associated with obesity-related inflammation, the beneficial role of n-3 polyunsaturated fatty acids and deleterious role of cholesterol, physical inactivity, hypertension-induced subchondral ischemia, dyslipidemia-induced ectopic lipid deposition in chondrocytes, hyperglycemia-induced local effects of oxidative stress and advanced glycation end-products, low-grade systemic inflammation, and obesity-related adipokines by inducing the expression of proinflammtory factors. Leptin levels in serum/plasma and synovial fluid were associated with joint pain, radiographic progression, bone formation biomarkers, cartilage volume, knee OA incidence, and total joint arthroplasty in OA patients. Elevated leptin expression and increased effect of leptin on infrapatellar fat pad, synovium, articular cartilage, and bone were also involved in the pathogenesis of OA. Current knowledge indicates a convincing epidemiologic association between MetS and OA, especially in the Asian population. Animal studies have also shown that metabolic dysregulation may lead to OA pathogenesis. Accumulating evidence suggests that leptin may play a potential role in OA pathogenesis. Therefore, leptin and its receptor may be an emerging target for intervention in metabolic-associated OA.