The randomized, double-blind, placebo-controlled clinical trial also found that supplementation with the citrus-pomegranate complex led to decreases in malondialdehyde (MDA), a marker of oxidative stress, and increases in nitrate (NO3) levels, an important signalling molecule involved in endothelial function that boosts vasodilation in smooth muscle cells.
“This study was the first to determine the effects of a combined citrus and pomegranate complex on physical fitness in an older study population,” wrote the researchers from Maastricht University and BioActor.
The study used BioActor’s Actiful branded ingredient, which is standardised for its content of the flavonoid 2S-hesperidin.
Sanne Ahles, lead author on the new paper and a clinical researcher at BioActor, commented: “We are pleased with the results of this clinical trial, which includes improvements both in physical fitness and mental well-being, as well as improved oxidative stress markers.
“These results have piqued our interest regarding potential underlying mechanisms of action, which are currently being investigated in our new clinical trial.”
The study included 36 active seniors aged between 60 and 75 who were randomly assigned to receive either placebo or with 700mg of the Citrus and Pomegranate Complex for four weeks. This was followed by a four-week washout period before crossing over to the other group for a further month.
Results indicated that four weeks of CPC supplementation led to significant improvements in handgrip strength in these healthy elderly subjects, compared to placebo.
“Improved handgrip strength has previously been associated with reduced all-cause mortality, as well as with increased cognitive function, mobility, and functional status,” wrote the researchers.
Commenting on the potential mechanism of action for handgrip strength, they proposed that this may be linked to improved mitochondrial function. Data from earlier in vitro experiments already showed that hesperetin – the main active metabolite of the CPC – may increase intracellular ATP production and mitochondrial spare capacity, they said.
In addition, data from the WHO-QOL-100 questionnaire, a list of 100 questions created by the World Health Organisation and validated to assess the quality of life, indicated that CPC supplementation was associated with significant improvements in a range of measures, including thinking, learning, memory, and concentration.
Significant reductions in MDA were also observed following CPC supplementation, decreasing by about 16% over four weeks, while levels increased during four weeks of placebo.
Nitrate levels also improved, said the researchers, but these changes were not statistically different between the groups.
“With age, the number and functionality of mitochondria decreases. Dysfunctional mitochondria have reduced the capacity for producing ATP – our muscles’ principal energy source. Therefore, the next step is to confirm the effect of CPC on mitochondrial biogenesis and functionality in humans in vivo,” said the researchers.
Source: Journal of Nutrition, Health & Ageing
Published online ahead of print, doi: 10.1007/s12603-022-1834-4
“The Effect of a Citrus and Pomegranate Complex on Physical Fitness and Mental Well-Being in Healthy Elderly: A Randomized Placebo-Controlled Trial”
Authors: S. Ahles et al.