Effect of intermittent and continuous caloric restriction on Sirtuin1 concentration depends on sex and body mass index

Trine B. Opstad,Serena Tonstad,Tine Sundfør,Ingebjørg Seljeflot

doi:10.1016/j.numecd.2021.03.005

Trine B. Opstad, Serena Tonstad + Show 2 more

Open Access

https://doi.org/10.1016/j.numecd.2021.03.005

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Abstract

Background & aimsThe favorable effect of caloric restriction (CR) on health span is well known and partly mediated by the sirtuin system. Sirtuin1, a regulator of energy homeostasis in response to nutrient availability, is activated by CR. We therefore investigated effects of two different CR regimens on Sirtuin1 concentrations. Methods & resultsThe study included 112 abdominally obese subjects, randomized to intermittent or continuous CR for 1 year. Blood samples and anthropometric measures were collected at baseline and after 12 months. Sirtuin1 concentrations were measured by ELISA. Sirtuin1 correlated significantly to BMI at baseline (r = .232, p = 0.019). Mean reduction in body-weight was 8.0 and 9.0 kg after intermittent and continuous CR, respectively. After 1 year, no significant between-group differences in Sirtuin1 levels were observed according to regimen (p = 0.98) and sex (p = 0.41). An increase in median Sirtuin1 concentrations (pg/mL) [25, 75 percentiles] from baseline was observed after intermittent CR in the total population (884 [624, 1285] vs.762 [530, 1135]; p = 0.041), most marked in men (820 [623, 1250] vs. 633 [524, 926]; p = 0.016). Improvement in BMI after 1 year correlated to Sirtuin1 changes, but varied according to sex. In women, Spearman's rho = .298, p = 0.034, with stronger correlation in the intermittent CR group (r = .424, p = 0.049). In men, there was an inverse relation to Sirtuin1 changes, only in the intermittent CR group (r = −.396, p = 0.045). ConclusionsEffects on Sirtuin1 concentrations after 1 year of CR are sex and BMI-related. Intermittent CR regimen affected Sirtuin1 to a stronger extent than continuous CR, suggesting individualized dietary intervention.

Highlights

The current study is a sub-study of a clinical trial that recruited 112 obese subjects with body mass index (BMI) 30e45 kg/m2, aged 21e70 years, into a randomized intervention trial on caloric restriction (CR) between 2015 and 2017 at Section of Preventive Cardiology, Department of Endocrinology, Morbid Obesity and Preventive Medicine at Oslo University Hospital in Norway [8]
Three dropouts occurred in the continuous caloric restriction (CCR) group versus four in the intermittent caloric restriction (ICR) group, resulting in 55 and 50 participants, respectively, completing the study
After 1 year, no statically significant difference in weight loss, BMI or waist and hip circumference reductions was observed between groups, with correspondingly 8.0 vs. 9.0 kg, 2.7 vs. 3.2 kg/m2, 8.7 vs. 9.6 cm and 6.8 vs. 7.5 cm in the ICR and CCR group, respectively [8]