The prevalence of MetOA globally is rising, and this is expected to be exacerbated by rising cases of obesity and the ageing population.
To address this health burden, oil from the greenshell mussel (Perna canaliculus) (GSM), a native New Zealand shellfish, has been successfully used to reduce osteoarthritis symptoms.
In this latest study, scientists from Massey University and the Cawthron Institute assessed the effect of including flash-dried powder from whole GSM meat as part of a normal (control) versus high-fat/high-sugar (HFHS) diet for 13 weeks on the development of MetOA in rats.
The rats were split into groups and fed four different diets:
1 - normal control diet (ND)
2- normal control diet supplemented with GSM (ND + GSM)
3- high-fat high-sugar diet (HFHS)
4- high-fat high-sugar diet supplemented with GSM (HFHS + GSM)
To evaluate the presence of early osteoarthritis in the rats’ joints, cartilage degradation was measured using the plasma biomarker C-terminus telopeptide of type II collagen (CTX-II).
The researchers wrote: “The results showed that rats fed the HFHS diet had a higher level of CTX-II than rats fed either of the NDs. Interestingly, including GSM in the diet slightly reduced CTX-II in the ND rats and significantly reduced CTX-II in the HFHS rats.”
They also examined cartilage degradation is the knee joins and found significant benefits among the HFHS group that also received GSM.
“This finding provides further evidence that GSM is protective against OA, and in the absence of changes in inflammatory markers suggests that GSM’s effects may be localized to the cartilage microenvironment,” they added.
The researchers stated that GSM's high omega-3 content was likely responsible for its anti-inflammatory and anti-arthritis benefits.
“GSM contains high levels of polyunsaturated fatty acids, especially the omega-3 PUFAs DHA and EPA,” they wrote.
“The anti-inflammatory and anti-arthritis effects of omega-3 PUFAs are well established. There is further evidence that omega-3s are important compounds in GSM with potential as anti-inflammatory and anti-arthritis bioactives.”
They concluded that results of the current study validated this and demonstrated the preventive effects of GSM against MetOA in a rat model.
“However, to date this effect has only been demonstrated in the early stage of MetOA; long-term effects of GSM and its potential ability to treat exacerbated OA in this model are still unknown and should be the subject of further investigation.”
"Such work may reveal additional biomarker changes to confirm ongoing MetOA and identify biomarkers useful for monitoring treatment,” they added.
The study was funded by the National Science Challenge, High value nutrition (HVN) “Musseling up: high-value Greenshell™ mussel foods” (UOAX1421).” MU College of Health PhD scholarship, as a collaboration between Massey University, Cawthron Institute, and Sanford Ltd.
“The Preventive Effects of Greenshell Mussel (Perna canaliculus) on Early-Stage Metabolic Osteoarthritis in Rats with Diet-Induced Obesity”
Authors: Parkpoom Siriarchavatana, et al.