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Item Traumatic brain injury and substance use disorder in Aotearoa New Zealand : characteristics, correlates, and the role of social cognition in an inpatient addictions treatment sample : a thesis presented in partial fulfilment of the requirements for the qualification of Doctor of Clinical Psychology at Massey University, Wellington, New Zealand(Massey University, 2025-11-25) Marshall, Hannah L. M.Traumatic Brain Injuries (TBIs) and Substance Use Disorder (SUD) often cooccur, yet the underlying mechanisms linking these conditions remain unclear. One potential explanation is that TBI disrupts neuropsychological functioning, particularly Social Cognition, thereby increasing the risk of SUD. The overall objective of this thesis is to explore these relationships in depth. To achieve this, the first study aimed to gather a detailed history of head-injury characteristics among individuals with SUD in Aotearoa, including TBI with loss of consciousness (LOC). By ascertaining these characteristics, the second study aimed to examine their association with neuropsychological outcomes. Third, our final study aimed to explore the potential role of Social Cognition in explaining the relationship between TBI and SUD. A total of 77 adults (aged 18-64) engaged in residential treatment for SUD, participated in the current research. During their residential treatment program, participants completed self-report questionnaires to ascertain head-injury, TBI and SUD history, mental health, and TBI-related symptom severity. Of this sample, 70 went on to complete neuropsychological tasks. Study 1 revealed that one hundred percent of the sample endorsed one or more lifetime head-injury events. 81.8% of the sample had experienced a self-reported TBI featuring LOC, with the remaining 18.2% having a history of a ‘possible TBI’ where they sustained a head-injury event without LOC. Overall, 91% sustained multiple lifetime head-injuries (either with or without LOC). Compared to the general New Zealand population, this sample featured a higher rate of TBIs of moderate severity, and most events were untreated. Many individuals sustained head-injuries at a young age and sustained repeated injuries into adulthood. Study 2 found that individuals who had a high number of lifetime head-injuries showed significantly lower scores on executive functioning and self-reported experiencing more cognitive difficulties. Study 3 found that within Social Cognition, the interpretation of complex social cues, particularly those involving deception and subtle social intentions, may mediate the relationship between TBI and SUD. This research contributes to identifying unique rates, patterns, and outcomes of head-injury including TBI among treatment-seeking substance users and highlights factors which may increase individuals’ vulnerability. Social Cognition appears to be a mechanism worthy of future exploration as it may explain the relationship between TBI and SUD. Implications of these results for treatment and rehabilitation and directions for future research are discussed.Item Neurobiological impacts of kiwifruit consumption in a pig model and its effects on sleep and mood in young adults : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Nutritional Sciences at Massey University, Palmerston North, New Zealand(Massey University, 2024) Kanon, Alexander PutraKiwifruit (KF) positively impacts gut health, specifically in alleviating gastrointestinal symptoms and improving laxation. Emerging evidence also suggests that consuming KF influences sleep and mood, with most studies indicating improvements in subjective measures of these attributes. Previous research has explored the mechanisms behind these effects using in vitro and rodent models, which have considerable differences to human physiology. This study explores the impact of New Zealand KF on various brain physiological aspects in animal models and humans. It explores the antioxidant neuroprotective potential of KF, examines alterations in the gut microbiome composition and bioamine concentrations, analyses temporal bioamine concentration effects in plasma and brain regions, and assesses the acute effects on human sleep quality and mood. Findings reveal that in one week, consumption of both green and gold KF reduced oxidative potential in plasma, increased concentrations of 5-Hydroxyindoleacetic Acid (5HIAA, a serotonin metabolite), and induced changes in the abundance of specific microbial genera along the colon of adult pigs, a more representative model of human physiology. Furthermore, green KF enhances antioxidant protective potential in plasma and various brain regions, while gold KF elevates plasma vitamin C levels and tends to reduce acetylcholinesterase activity across the entire brain. Temporal effects highlight distinct patterns in metabolite concentrations between green and gold KF, with γ-Aminobutyric Acid (GABA) and serotonin exhibiting notable interactions in different brain regions. Good and poor sleepers consuming KF before sleep had improved sleep quality and mood. Fresh KF facilitates easier sleep onset for good sleepers, while freeze-dried KF leads to increased ease of awakening in the morning for poor sleepers. Notably, both forms of KF increase the urinary excretion of 5HIAA and reduce feelings of sleepiness while increasing alertness. The inclusion of the fruit skin appears to increase improvements in sleep quality, suggesting a more noticeable effect. These studies provide valuable insights into the neurobiological effects of KF and support its potential as a functional food to improve sleep in humans.Item Shining a light on recovery : investigating the effectiveness of bright light therapy in mitigating fatigue after mild traumatic brain injury : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Clinical Psychology at Massey University, New Zealand(Massey University, 2023) Connolly, Kathryn MarieFatigue is a common and debilitating symptom experienced by individuals following a mild traumatic brain injury (mTBI). Despite its prevalence, post-mTBI fatigue remains a challenging, and at times misunderstood condition, with a scarcity of scientifically evidenced treatment approaches. The complexity of fatigue's underlying causes in this population calls for further research. Recognising its significant impact on individuals' quality of life emphasises the need to identify effective interventions and enhance symptom management. This study aims to investigate the potential effectiveness of daily bright light exposure as a non-invasive intervention to alleviate fatigue in the post-mTBI population. While existing research has shown positive outcomes for bright light therapy in managing fatigue in broader traumatic brain injury populations, the current study focuses on individuals with injuries at the mild end of the spectrum, offering valuable insights into the efficacy of this treatment in a more targeted context. The primary objective of the research was to investigate whether daily bright light exposure effectively reduced fatigue symptoms in individuals with mTBI. Additionally, the study aimed to explore the impact of light exposure on secondary outcomes, including daytime sleepiness, sleep quality, depression, anxiety, stress, and circadian rest-activity cycles. To address recruitment challenges, a randomised multiple baseline controlled trial design was adopted. The results revealed that all nine participants consistently experienced significant fatigue throughout the study. Fatigue levels appeared to decrease during the bright light therapy sessions suggesting a potential positive impact of bright light exposure on fatigue, although this reduction was not statistically significant across the group. Due to limitations in data, the ability to confidently demonstrate efficacy was low and this prompted a shift in focus towards assessing the feasibility of conducting research of this nature. Moving forward, future studies can benefit from an understanding of the complexities involved in implementing intensive intervention protocols. The current study demonstrates a need for close collaboration with participants to monitor adherence and potential side effects, alongside coordination with colleagues in the mTBI field to ensure access to a sufficient participant pool for achieving statistically significant results. Overall, this research provides some limited evidence of positive effects from bright light therapy for select individuals and contributes to the expanding body of evidence investigating light as a potential intervention for alleviating fatigue symptoms post-mTBI. More importantly, by shedding light on the hurdles in implementing such interventions among individuals with mTBI, it contributes to the development of targeted and potentially effective interventions for improving the quality of life for individuals affected by this condition. It is hoped that this study contributes to the broader literature aimed at facilitating better outcomes for individuals with mTBI and related fatigue symptoms.Item The tale of the shear-thickening mamaku polysaccharide, from forest to gut : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy (Food Technology), Massey University, Palmerston North, New Zealand. EMBARGOED until further notice.(Massey University, 2023) Bisht, AkshayThe New Zealand black tree fern (Cyathea medullaris, ‘mamaku’ in the Māori language) is grown across the Pacific Islands and has a long history of use for therapeutic benefits or as food by Māori people. The water-soluble gum extract from mamaku fern contains a novel glucuronomannan biomacromolecule, called mamaku polysaccharide (MP), which has been shown to exhibit a unique shear-thickening (i.e., increase in viscosity on shearing) behaviour at a similar shear rate as that found in the human stomach. Herein, the objective was to gain a better technical and physiological understanding of MP for designing a novel shear-thickening ingredient for the industry with proven effects in humans. The shear-thickening behaviour of MP was sensitive to the harvesting age of mamaku fronds and industrial operations such as high temperature and shear. With the increase in harvesting age, the molecular weight of MP reduced, which consequently reduced the shear viscosity. The shear-thickening behaviour was lost in MP from old fronds. Furthermore, the temperature treatment disintegrated the backbone of MP into smaller fragments which caused a reduction in viscosity and extent of shear-thickening. Similar rheological trends were observed post-shear treatment, however, there was no evidence of depolymerisation. A combination of in vitro models revealed that mamaku gum extract could improve host gut functioning by reducing the activity of digestive enzymes (α-amylase, pepsin and lipase) and binding bile acids. Mamaku gum can act as a substrate for colonic fermentation, promote the production of short-chain fatty acids and alter the colonic microbial composition. Upon ingesting mamaku gum, the shear-thickening behaviour may develop in the oesophagus causing a possible choking hazard. Therefore, the potential of using the whole pith—natural entrapment of MP in the tissue of pith—as an alternative to gum extract was studied. Freeze-dried pith was ground to powder. The powder particles swelled upon rehydration with water and released the water-soluble MP into the continuous phase in a time-dependent manner. The presence of enough MP in the continuous phase to form polymer-polymer interactions resulted in a shear-thickening behaviour of the pith powder suspension similar to the MP extract solution. Moreover, the co-consumption of 1 h pre-hydrated mamaku pith powder with a carbohydrate-rich meal significantly reduced the postprandial glycaemic response (blood glucose peak height) in human participants. Additionally, the consumption of mamaku pith powder in rats could alter colonic microbiota. Interestingly, more than half of the MP (uronic acid) consumed by rats survived the gut transition and was obtained in faeces, suggesting that MP could potentially be used as a laxative. Thus, mamaku pith could be used as an alternative to gum extract to develop a natural shear-thickening ingredient which may potentially help to manage diabetes and improve colon health.Item Effect of New Zealand Greenshell™ mussel on osteoarthritis biomarkers and inflammation in healthy postmenopausal women : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Nutritional Science, School of Health Sciences, Massey University, Palmerston North, New Zealand(Massey University, 2023) Abshirini, MaryamNew Zealand GreenshellTM Mussel (GSM) showed chondroprotective effects in a pre-clinical study using a rat model of metabolic osteoarthritis, warranting further assessment in a human study. This PhD project aimed to assess the effect of GSM supplementation on cartilage degradation biomarkers in humans, and to develop novel biomarkers through a metabolomic approach. A double-blind, placebo-controlled, longitudinal clinical trial was carried out in overweight postmenopausal women who were given 3 g/day whole meat GSM powder or placebo (sunflower seed protein) for 12 weeks. Plasma samples from the pre-clinical rat trial were assessed through an untargeted metabolomic approach, followed by metabolomic analysis of plasma samples from the clinical trial. In participants with active knee pain, the cartilage turnover biomarker C-terminal telopeptide of type II collagen was significantly lower in GSM participants compared to placebo at weeks 6 and 12. GSM significantly reduced joint pain and improved knee-related symptoms. GSM but not placebo altered the faecal microbiota population and reduced the rate at which body fat accumulation increased. However, no changes in inflammatory cytokines were found. The metabolomic analysis of rat plasma samples revealed that GSM supplementation regulated the alteration in plasma triglyceride and other lipids caused by a high-fat diet. In the plasma of human participants, GSM supplementation increased long-chain polyunsaturated fatty acids (PUFA), ceramide, and some other lipids. In both rats and humans, GSM suppressed the sphingomyelin synthesis pathway. Polar metabolites including threonine, histidine and pipecolic acid were significantly impacted in both rat and human and are potential metabolic biomarkers for the impact of GSM powder supplementation in metabolic osteoarthritis. In conclusion, consumption of GMS powder may provide cartilage protection and reduce joint pain, particularly in women with symptomatic knees. However, no significant impact was observed on circulating inflammatory cytokines, suggesting that GSM may exert anti-inflammatory effects at the microenvironmental rather than systemic level. The bioactive compounds present in GSM powder such as omega-3 PUFA and chondroprotective glycosaminoglycans may be responsible for the beneficial effect through inhibiting the breakdown of type II collagen in cartilage, regulating gut microbe abundance, improving body composition, and the metabolite profile which needs to be investigated in future research.Item Effect of Kiwifruit actinidin on the digestion of gluten proteins : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Nutritional Sciences at Massey University, Palmerston North, New Zealand(Massey University, 2022) Jayawardana, Isuri AchinthaGluten proteins are resistant to complete proteolysis by the human gastrointestinal tract (GIT) enzymes, due to their high proline- and glutamine-rich peptide sequences. Proline confers resistance to proteolysis by digestive enzymes, producing indigestible proline-rich peptides, some of which can trigger immunogenic reactions that are responsible for gluten-related health disorders such as coeliac disease, wheat allergy and gluten sensitivity. At present, gluten-free diets (GFD) are the only promising therapy for gluten-related health disorders. However, maintaining a lifelong GFD is challenging. As an alternative therapy, gluten-specific enzymes to hydrolyse immunogenic peptides have shown promising results. Most of these are of microbial origin. Identification of natural alternative enzymes is desirable, with fruit-borne enzymes a possible solution. Actinidin, a cysteine protease found in most green kiwifruit (Actinidia deliciosa), is suggested as an effective exogenous enzyme, to be utilized in this category. The objective of this PhD study was to evaluate the effect of actinidin on the digestion of gluten and gluten-derived immunogenic peptides in the GIT. The effectiveness of actinidin was tested using different in vitro GIT models and an animal (pig) preclinical model with purified gluten or whole wheat bread as sources of gluten, and purified actinidin or and fresh green kiwifruit as sources of actinidin. Analytical techniques such as free amino nitrogen determination, enzyme-linked immunosorbent assay and both targeted and untargeted mass spectrometry were used to determine the degree of hydrolysis (DH), R5 gluten epitopes and immunogenic peptides respectively. Actinidin hydrolysed peptide bonds adjacent to proline residues in the 33-mer peptide, one of the most immunogenic gluten peptides. The gastric DH of gluten proteins was influenced by an interaction between pH and actinidin concentration (P < 0.05). Actinidin at a concentration of > 2.7 U/mL and pH > 2 during hydrolysis was considered ideal for gluten hydrolysis. Actinidin increased (P < 0.05) the rate of acceleration of DH of gluten and reduced the amount of R5 epitopes present in the small intestine using a semi-dynamic in vitro GIT digestion model. Actinidin also accelerated the gastric hydrolysis of wheat proteins in whole wheat soda bread, which was reflected in a faster reduction of R5 epitopes in the gastric conditions and the rate of reduction (P < 0.05) of most of the immunogenic marker peptides present in the small intestine. In vivo, the presence of dietary actinidin in the form of green kiwifruit significantly (P < 0.01) enhanced the gastric digestion of wheat proteins in whole wheat soda bread fed to pigs as a model of human GIT digestion. The amount of R5 epitopes was lower (P < 0.01) in the stomach, proximal and distal small intestine and terminal ileum of pigs fed diets containing green kiwifruit (P <0 .05). The number of immunogenic peptides in the proximal small intestine was low in the pigs fed green kiwifruit diet compared to that of the pigs fed yellow kiwifruit diet (control). In addition, a diet containing green kiwifruit markedly reduced (P < 0.05) the amount of seven gluten immunogenic marker peptides including the 33-mer peptide in the stomach chyme of pigs. Actinidin was able to survive peptic proteolysis and gastric pH conditions until 300 min postprandial in pigs. Taken together, these results suggest that actinidin enhanced the rate of proteolysis of both purified gluten and gluten in a food matrix and reduced the amount of immunogenic gluten epitopes reaching the small intestine during GIT digestion in vitro and in vivo. Actinidin was able to reduce both the amount of and the time of exposure to immunogenic peptides in the small intestinal lumen, therefore it is a promising candidate to be considered in oral enzyme therapy for gluten-related health disorders.Item Performing pūrākau : liberating bodies, healing wairua, and reclaiming ancestral wisdom : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Psychology at Massey University, Wellington, New Zealand(Massey University, 2021) Pearse-Otene, HelenStudies by government agencies and advocacy groups report that Māori women and children are more vulnerable to experiencing family violence, sexual abuse, and incest than Pākehā. They acknowledge colonisation and historical trauma as contributing factors, and call for a systems-focused response to tackling sexual violence. This includes providing access to contextually responsive and culturally appropriate interventions. This study initially aimed to explore traditional Māori understandings of incest and healing from sexual trauma that are embedded in the pūrākau (ancestral story) of Hinetītama/Hinenui Te Pō, and her parents, Hineahuone and Tānemahuta. As it would apply a unique Māori theatre pedagogy called Theatre Marae, the project was then expanded to investigate the utility and potential of this innovative approach, which draws together Māori and non-Māori performance traditions, therapeutic models, Māori language, and customs in a process for creative inquiry. In pursuing these two activities, the resulting thesis comprises three publications. In the first article (chapter 2), I unpack the conceptual framework of Theatre Marae pedagogy as a suitable approach for kaupapa Māori (by Māori, for Māori) arts-based research against the backdrop of growing scholarship in Indigenous research and psychologies. In the second article (chapter 3), I deepen this exploration into Theatre Marae and its core methods within an historical account of the theatre company most associated with the practice, Te Rākau. The third article (chapter 4) builds on the preceding chapters by returning to the initial focus of this study and describing how Theatre Marae was applied in a performance-based analysis of this ancient pūrākau as a narrative of survival and healing. The analysis revealed new themes that highlight the collectivist customs of traditional Māori society as protective factors against the proliferation of sexual violence and incest. When drawn together in this thesis, these articles and contextualising discussion illustrate how Māori ancestral knowledge can inform the development of more culturally responsive therapies for recovery from historic sexual trauma. Furthermore, in presenting Theatre Marae to the realm of kaupapa Māori research, this thesis contributes to an international agenda to decolonise research in ways that are emancipatory, healing, and transformative for Indigenous communities.Item Effects of whole greenshell mussel (Perna canaliculus) powder on macrophage, osteoblast, and chondrocyte cell models of metabolic osteoarthritis : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Health Sciences at Massey University, Palmerston North, New Zealand(Massey University, 2021) Rizwan, SaimaOsteoarthritis (OA) is a chronic, painful disorder of synovial joints in the hands, knees, hips, and spine. It is characterized by articular cartilage degeneration, subchondral bone sclerosis, and synovium inflammation. Obesity is an important risk factor, by exerting additional mechanical loading on the joints and by increasing the hormone leptin (LEP). LEP, an adipokine produced by white adipose tissue, is important in regulating the metabolic activities of inflammatory, cartilage and bone cells in OA pathogenesis. OA has no cure and is conventionally managed with painkilling medications. Oil from New Zealand GreenshellTM mussel (GSM) is also used to treat OA, but its mechanism of action is unclear, and it is not known whether peptides and other components in whole GSM may have additional health benefits in OA. This study investigated the effects of whole GSM using novel in vitro models of OA. LEP-stimulated J774A.1 macrophages, MC3T3-E1 pre-osteoblasts and differentiated osteoblasts, and ATDC5 pre-chondrocytes and differentiated chondrocytes modelled the behaviour of synovial macrophages, subchondral bone, and cartilage cells during OA. Blue mussel (BM) and GSM extracts were used to optimise macrophage assay conditions. Two whole GSM extracts were further tested in the in vitro models at non-cytotoxic concentrations. RT-qPCR was used to quantify biomarkers; chemical and staining assays were used to assess alkaline phosphatase activity and mineralization, proteoglycan, and collagen synthesis. LEP-induced inflammatory cytokine expression in macrophages peaked at 4 and was dose-dependent; neither mussel type ameliorated inflammation but BM alone significantly induced IL-1β, IL-6, TNF-α and IL-10 expression. GSM significantly increased osteoblast proliferation, mineral deposition, and expression of osteogenic markers Alp, Osx, Col10α1 and Runx2. In chondrocytes, GSM significantly blocked LEP-induced hypertrophic differentiation by suppressing alkaline phosphatase, Col10α1 and mineralized nodules and increasing Sox9 expression. This project developed simple but effective in vitro models of inflammatory, bone, and cartilage cells that mimic the physiological response to LEP and the pathological changes observed in OA and demonstrated that whole GSM may prevent OA by acting directly on bone and cartilage rather than acting through well recognized anti-inflammatory pathway, indicating novel protective effects of whole GSM on all three cell types.Item Characterizing New Zealand forest grown ginseng (Panax ginseng C.A. Meyer and Panax quinquefolius L.) : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Nutritional Science at Massey University, Palmerston North, New Zealand(Massey University, 2021) Chen, WeiGinseng is a slow-growing perennial herbaceous plant of the genus Panax (Araliaceae family). Ginseng root has been a significant source for natural medicines and has been used for thousands of years in East Asia. Ginsenosides are the unique and bioactive components in ginseng. They are affected by the growing environment and conditions. With the increasing demand for ginseng, wild ginseng is becoming rare, and most of the world’s supply of ginseng is from farmed ginseng. In New Zealand (NZ), ginseng has been grown as a secondary crop under a pine tree canopy with an open wild environment for more than 15 years. However, there is neither research on the chemical composition of NZ grown ginseng, nor reports on its biological activity. In this thesis, an LC-QTOF-MS/MS method was developed for characterizing and quantifying ginsenoside components of NZ-grown ginseng. A total of 102 ginsenosides were detected and identified from NZ-grown P. ginseng. The total content of ginsenosides in various parts of ginseng varied and was not dependent on age. In the underground parts, ginsenosides Rb1, mRb1, and Re were the main components. Furthermore, the average content of total ginsenosides in NZ-grown ginseng was 40.1 ± 3.2 mg/g (n = 14), which showed significantly (p < 0.05) higher concentration than that of China-grown ginseng (16.5 ± 1.2 mg/g, n = 113) and Korea-grown ginseng (21.1 ± 1.6 mg/g, n = 106). The individual ginsenosides Rb1, Re, Rf, and Rg1 from NZ-grown ginseng were 2.2, 2.9, 1.7, and 1.3 times higher than that of ginseng grown in China, respectively. In addition, fifty and forty-three ginsenosides were identified from various parts of NZ-grown P. ginseng and NZ-grown P. quinquefolius L., respectively, and 29 ginsenosides were found in both ginseng species. In both plants, concentration of Rb1 was highest in the underground parts (fine root, rhizome, and main root), and ginsenoside Re was highest in the aboveground parts (stem and leaf). In terms of improving the use of ginseng resources, ginseng leaves can be made into black ginseng leaves by steaming for ginsenoside transformation, and the less-polar ginsenoside (Rg3) can be greatly enriched through converting major ginsenosides in the post-harvest process, such as high temperature treatment at low pH. THP-1 cell line was used to evaluate the effects of different NZ-grown ginseng fractions on the productions of inflammatory cytokines. Less-polar ginsenoside fraction extracts (LPG) showed stronger anti-inflammatory effects than high-polar ginsenoside fraction extracts (HPG) on inhibiting pro-inflammatory cytokine (TNF-α, IL-1β, and IL-6) production. Particularly, 100 µg/mL LPG not only significantly inhibited the production of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6, but also remarkably enhanced the production of anti-inflammatory cytokine IL-10. This thesis fills a gap in the chemical composition and biological activity of NZ-grown ginseng and provides methods for improving active components through the post-harvest process.Item The preventive effect of greenshell mussel meat against osteoarthritis in vivo : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Health Science At Massey University, Palmerston North, New Zealand(Massey University, 2021) Siriarchavatana, ParkpoomOsteoarthritis (OA) is identified by progressive cartilage erosion of synovial joints. One of the most prevalent OA phenotypes, metabolic OA (MetOA), is linked to metabolic syndrome (MetS). MetS is a combination of obesity, type II diabetes, hypertension, and hyperlipidemia; the effects of these disorders can lead to the development of MetOA. Osteoporosis is characterised by loss of bone mineral density and is causally linked with a decrease in systemic estrogen levels. As MetS, OA and osteoporosis are all prevalent in postmenopausal women, it is possible they may be causally linked. For example, systemic low-grade inflammation in MetS may trigger inflammation in both joints and bone, which could be further aggravated by high fat/high sugar diet (HFHS)-induced obesity and gut dysbiosis. We hypothesized that chronic inflammation would be correlated with MetOA development and therefore decreasing inflammation would be protective. New Zealand greenshell mussel (GSM) contains anti-inflammatory properties shown to reduce OA symptoms and omega-3 fatty acids shown to reduce the development of post-menopausal osteoporosis. We hypothesized GSM could protect against both MetOA and osteoporosis reducing bone resorption, inhibiting inflammation and/or modulating beneficial gut microbes. In vitro, non-polar GSM lipids demonstrated bone-protective properties and significantly reduced osteoclast differentiation, tartrate-resistant acid phosphatase activity, actin ring formation and gene expression of matrix metalloproteinase, cathepsin K, carbonic anhydrase and nuclear factor of activating T cells 1. In vivo, aging, HFHS and OVX produced a rat model mimicking human MetS. Dietary whole GSM powder provided protection by significantly reducing a biomarker of collagen degradation and subsequent joint damage, as well as improving short-term bone mineral density and lean mass accrual. GSM-induced changes in gut microbiota were not correlated with dysbiosis. No changes in inflammatory markers were found, disproving our initial hypothesis and suggesting that chronic inflammation may not be a critical factor in MetOA. In conclusion, GSM as a dietary intervention may reduce the incidence or progression of MetOA but not via altering systemic inflammation or gut dysbiosis.
