Regiospecific Analyses of Triacylglycerols of Hoki (Macruronus novaezelandiae) and Greenshell™ Mussel (Perna canaliculus)

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.

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.

Marine omega-3 (n-3) phospholipids: A comprehensive review of their properties, sources, bioavailability, and relation to brain health

For several decades, there has been considerable interest in marine-derived long chain n-3 fatty acids (n-3 LCPUFAs) due to their outstanding health benefits. n-3 LCPUFAs can be found in nature either in triglycerides (TAGs) or in phospholipid (PL) form. From brain health point of view, PL n-3 is more bioavailable and potent compared to n-3 in TAG form, as only PL n-3 is able to cross the blood-brain barrier and can be involved in brain biochemical reactions. However, PL n-3 has been ignored in the fish oil industry and frequently removed as an impurity during degumming processes. As a result, PL products derived from marine sources are very limited compared to TAG products. Commercially, PLs are being used in pharmaceutical industries as drug carriers, in food manufacturing as emulsifiers and in cosmetic industries as skin care agents, but most of the PLs used in these applications are produced from vegetable sources that contain less (without EPA, DPA, and DHA) or sometimes no n-3 LCPUFAs. This review provides a comprehensive account of the properties, structures, and major sources of marine PLs, and provides focussed discussion of their relationship to brain health. Epidemiological, laboratory, and clinical studies on n-3 LCPUFAs enriched PLs using different model systems in relation to brain and mental health that have been published over the past few years are discussed in detail.

The role of fatty acids and triglycerides in the gonads of Paracentrotus lividus from Sardinia: Growth, reproduction and cold acclimatization

A detailed characterization of lipid extracts from gonads of P. lividus over a year has been performed combining GC and NMR measurements. For this purpose, sea urchins from two different Sardinian coastal areas were collected monthly. The results underlined a correlation between gonad fatty acids profiles and both water temperature and reproduction process. In particular, EPA and ARA appear to be the most altered fatty acids following seasonal changes. It is suggested that EPA could represent a biomarker of reproduction, reaching a content around 14% during gametogenesis, mainly due to an increase of the sn-1,3 position in TAGs. On the contrary, ARA seems to play a more important role in response to cold acclimatization, which is reflected in a modulation of ARA content in the sn-1,3 position in TAGs.

Lipid profiles, in vitro digestion and oxidative stability of mutton bird oil

The lipid profile, in vitro digestion and oxidative stability of mutton bird oil were investigated. Wax ester, triacylglycerol and sterol were the major lipids present as determined using capillary chromatography with flame ionisation detector (Iatroscan). Fatty acid analysis by gas chromatography (GC) showed that wax esters had a higher total omega-3 fatty acids content including EPA, DPA and DHA than TAGs (31 % and 24 %, respectively). In TAGs, (13)C nuclear magnetic resonance (NMR) data showed that EPA was statistically positioned at sn-1,3 and sn-2, while DHA was preferentially at sn-2. In vitro digestion using porcine pancreatic lipase resulted in 75 % of TAG and 10 % wax ester hydrolysis in 120 min. As reflected in the measured conjugated dienes (CD) and thiobarbituric acid reactive substances (TBARS) values during accelerated oxidation at 60 °C for 5 days, the oil was relatively stable against oxidation considering its high omega-3 content.

Purification of Alaskan walleye pollock (Gadus chalcogrammus) and New Zealand hoki (Macruronus novaezelandiae) liver oil using short path distillation

The beneficial health effects of a diet rich in n-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA) have been extensively researched in recent years. Marine oils are an important dietary source of n-3 LC-PUFA, being especially rich in two of the most important fatty acids of this class, EPA (eicosapentaenoic acid; 20:5n-3) and DHA (docosahexaenoic acid; 22:6n-3). Oils rich in n-3 LC-PUFA are prone to oxidation that leads to loss of product quality. Alaskan pollock (Gadus chalcogrammus Pallas, 1814) and New Zealand’s hoki (Macruronus novaezelandiae Hector, 1871) are the highest volume fisheries of their respective countries. Both produce large quantities of fishery byproducts, in particular crude or unrefined n-3 LC-PUFA containing oils. Presently these oils are used as ingredients for animal feed, and only limited quantities are used as human nutritional products. The aim of this research was to investigate the applicability of short path distillation for the purification of pollock and hoki oil to produce purified human-grade fish oil to meet quality specifications. Pollock and hoki oils were subjected to short path distillation and a significant decrease in free fatty acids and lipid oxidation (peroxide and para-anisidine values) products was observed. Purified oils met the Global Organization for EPA and DHA Omega-3 (GOED) standard for edible fish oils.

Detailed distribution of lipids in Greenshell™ mussel (Perna canaliculus)

Greenshell™ mussels (GSM-Perna canaliculus) are a source of omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA). Farmed GSM are considered to be a sustainable source of LC-PUFA as they require no dietary inputs, gaining all of their oil by filter-feeding microorganisms from sea water. GSM oil is a high-value product, with a value as much as 1000 times that of fish oils. GSM oil has important health benefits, for example, anti-inflammatory activity. It also contains several minor lipid components that are not present in most fish oil products, and that have their own beneficial effects on human health. We have shown the lipid content of the female GSM (1.9 g/100 g ww) was significantly greater than that of the male (1.4 g/100 g ww). Compared with male GSM, female GSM contained more n-3 LC-PUFA, and stored a greater proportion of total lipid in the gonad and mantle. The higher lipid content in the female than the male GSM is most likely related to gamete production. This information will be useful to optimize extraction of oils from GSM, a local and sustainable source of n-3 LC-PUFA.