Advancements in high-throughput technology provide new opportunities for omics research to understand the pathological process of various complex human diseases. The integration of multi-omics technologies can systematically reveal the interactions among aging molecules from a multidimensional perspective.
Aging is the main risk factor for chronic diseases that limits a healthy lifespan. Therefore, the mechanism of aging is a potential therapeutic target. Age correlation analyses involve large amounts of data obtained from various omics analyses, such as genomics (epigenomics), transcriptomics, proteomics, metabolomics, and microbiomics. We elaborated in detail in the Wu L. et al. [45] literature, 4.1 Aging Genomics, 4.1.1 Aging Epigenomics, 4.1.2 Aging Gene Expression, 4.1.3 Telomere-Based Biomarkers, 4.2 Aging Transcriptomics, 4.2.1Transcriptomics -Based Biomarkers, 4.2.2 MiRNAs, lncRNAs, and circRNAs-Based Biomarkers, 4.3 Aging Proteomics, 4.3.1 Proteomics-Based Biomarkers, 4.3.2 Senescence-Associated Secretory Phenotype-Based Biomarkers, 4.4 Aging Metabolomics, 4.5 Aging Microbiomics, 4.6 Early Biomarkers of AgingThe main advantages of this method include the analysis of all possible data pertaining to a single person or a large group of people, as well as the common and individual characteristics from a multi-dimensional perspective and the identification of aging markers and novel antiaging targets. Machine learning methods based on deep neural networks are the latest and most complex methods for identifying human aging biomarkers. They can utilize any type of omics data to predict age.
5. Integromicsand Systems Biology
To promote the multidimensional analysis of data, advanced omics technology is inseparable from advanced omics analytical tools. At present, large-scale, high-quality, and high-throughput data from various omics methods can be efficiently and independently analyzed. However, separate data analysis and interpretation ignore the correlation and biological interference between different omics levels. Therefore, the integration of single-omics methods is essential for an in-depth understanding of the aging process and its mechanism.
Integromics, the comprehensive analysis of different omics data, and systems biology have provided several breakthroughs in the study of aging and antiaging interventions. Together, they have emerged as a more complex statistical method and combine the experimental data obtained in multiple omics methods with computational models to provide a holistic view of the aging landscape [46]. Considering the complexity and heterogeneity of aging, integromics and systems biology not only provide static maps of molecules but are also used to characterize the mutual changes of molecules over time. This helps determine the optimal time point for aging biomarker measurements and specific antiaging drug treatments. Each omics-level biomarker candidate based on integromics and systems biology has biological relevance. Significant biomarker candidates can be preferentially used as biomarkers of aging in medicine and as new antiaging targets.
6. Conclusions and Prospects
Rapid advances in science and technology have accelerated the arrival of the “omics era”, thereby enabling researchers to collect and integrate data at different molecular levels. The identification of biomarkers of aging and new targets for antiaging interventions is crucial in aging biology and geriatrics. The multi-level information obtained through multi-omics technology contributes to the increased understanding of the mechanisms of aging and provides new opportunities for the diagnosis and treatment of aging and aging-related diseases.
We have summarized the various omics techniques used to characterize aging biomarkers. Each screened biomarker is a promising candidate and can be integrated into an “aging biomarker library” that can serve as a diagnostic and prognostic tool. Here, we mainly categorized them based on the existing biomarkers of aging. We summarized the recent omics methods used to discover biomarkers in genomics, transcriptomics, proteomics, metabolomics, and metagenomics (Figure 1).
Figure 1. Multi-omics-based technologies for characterizing aging clocks and biomarkers. Aging is a comprehensive process affected by multiple factors that is associated with changes at the molecular, cellular, tissue, and organism levels, thus requiring objective analytical research tools. The integrated multi-omics approach is essential to achieve a comprehensive understanding of the biological mechanisms of aging.
In the context of personalized and precision medicine, multi-omics methods have attracted widespread attention, because they can provide an in-depth understanding of the molecular patterns and cover a wide range of characteristics, such as participating in the metabolic, genetic, and signal transduction pathways of complex aging [47]. Therefore, we suggest that a combination of multiple biomarkers for a comprehensive diagnosis and systematic analysis can objectively characterize the aging process (Figure 2).
Figure 2. Schematic diagram of an integrated multi-omics approach to the research and application of aging biomarkers. Genomics, transcriptomics, proteomics, metabolomics, and microbiomics enable the high-throughput quantitative profiling of molecules in biological systems to reveal aging-related changes. Combining single-omics data with integromics and systems biology contributes to an increased understanding of the mechanisms of aging and paves the way for the development and utilization of aging biomarkers and novel antiaging targets.
Advances in computer science, including meta-analysis and artificial intelligence, are expected to remarkably increase the speed and efficiency of aging biomarker research [48]. However, before their application in the clinical setting, candidate biomarkers should be verified. This verification process must include larger sample populations. Despite the large gap between the identification of useful biomarkers and their application in clinical practice, the integrated analysis of multi-omics data is a promising tool to identify new candidate biomarkers that could be developed and used to identify pharmaceutical targets and improve human health during aging, thereby advancing our understanding of the pathophysiology of the complex and dynamic process of aging.