Adipose tissue is the largest and most active endocrine organ, involved in regulating energy balance, glucose and lipid homeostasis and immune function. Adipose tissue aging processes are associated with brown adipose tissue whitening, white adipose tissue redistribution and ectopic deposition, resulting in an increase in age-related inflammatory factors, which then trigger a variety of metabolic syndromes, including diabetes and hyperlipidemia. Metabolic syndrome, in turn, is associated with increased inflammatory factors, all-cause mortality and cognitive impairment. There is a growing interest in the role of nutritional interventions in adipose tissue aging. Nowadays, research has confirmed that nutritional interventions, involving caloric restriction and the use of vitamins, resveratrol and other active substances, are effective in managing adipose tissue aging’s adverse effects, such as obesity. In this review we summarized age-related physiological characteristics of adipose tissue, and focused on what nutritional interventions can do in improving the retrogradation and how they do this.

Brown adipose tissue (BAT) is of great importance in rodents for maintaining their core temperature via non-shivering thermogenesis in the mitochondria. BAT′s thermogenic function has been shown to decline with age. The activation of adenosine 5′-monophosphate (AMP)-activated protein kinase/sirtuin-1 (AMPK/Sirt-1) is effective in regulating mitochondrial function. Exogenous nucleotides (NTs) are regulatory factors in many biological processes. Nicotinamide mononucleotide (NMN), which is a derivative of NTs, is widely known as a Sirt-1 activator in liver and muscle, but the effect of NMN and NTs on aging BAT has not been studied before. The purpose of this study was to investigate the effect of NTs on aging senescence-accelerated mouse prone-8 (SAMP8) mice. Senescence-accelerated mouse resistant 1 (SAMR1) mice were set as the model control group and NMN was used as the positive control. Male, 3 month old SAMP8 mice were divided into the SAMP8-normal chow (SAMP8-NC), SAMP8-young-normal chow (SAMP8-young-NC), NMN, NTs-free, NTs-low, NTs-medium, and NTs-high groups for long-term feeding. After 9 months of intervention, interscapular BAT was collected for experiments. Compared to the SAMP8-NC, the body weight and BAT mass were significantly improved in the NT-treated aging SAMP8 mice. NT supplementation had effects on oxidative stress in BAT. The concentration of malondialdehyde (MDA) was reduced and that of superoxide dismutase (SOD) increased significantly. Meanwhile, the expression of the brown adipocyte markers uncoupling protein-1 (UCP-1), peroxisome proliferator-activated receptor-γ coactlvator-1α (PGC-1α), and PR domain zinc finger protein 16 (PRDM16) were upregulated. The upregulated proteins may be activated via the Sirt-1 pathway. Thus, NT supplementation may be helpful to improve the thermogenesis of BAT by reducing oxidative stress and activating the Sirt-1 pathway.

As one of the most important barriers in the body, the intestinal barrier is a key factor in maintaining human health. Ageing of the intestine is a degenerative process that is closely associated with a variety of poor health conditions in the elderly. Inflammation and the immune system are anti-ageing targets that can regulate the function of the intestine. Nucleotides (NTs) are involved in important physiological and biochemical reactions in the body, but there are few studies about their effect on the ageing intestine. This paper examines the role of exogenous NTs in the ageing intestine. For this purpose, we used senescence-accelerated mouse prone-8 (SAMP8) mice and senescence-accelerated mouse resistant 1 (SAMR1) mice for the experiment, and randomly divided the mice into NTs-free, Normal Control, NTs-low, NTs-medium, NTs-high, and SAMR1 groups. After 9 months of intervention, we collected the colon tissue of mice for testing. In our study, exogenous NTs could increase bodyweight of mice during ageing and improve the morphological structure of the intestine, and we found that NTs could promote the secretion of intestinal protective factors, such as TFF3 and TE. Furthermore, supplementation with NTs suppressed intestinal inflammation and improved intestinal immunity, possibly by activating the p38 signaling pathway. These results suggest that exogenous NTs are able to maintain the health condition of the ageing intestine.