Research hotspots and trends for axon regeneration (2000–2021): a bibliometric study and systematic review

Abstract

Background Axons play an essential role in the connection of the nervous system with the rest of the body. Axon lesions often lead to permanent impairment of motor and cognitive functions and the interaction with the outside world. Studies focusing on axon regeneration have become a research field with considerable interest. The purpose of this study is to obtain an overall perspective of the research field of axonal regeneration and to assist the researchers and the funding agencies to better know the areas of greatest research opportunities. Methods We conducted a bibliometric analysis and Latent Dirichlet Allocation (LDA) analysis of the global literature on axon regeneration based on the Web of Science (WoS) over the recent 22 years, to address the research hotspots, publication trends, and understudied areas. Results A total of 21,018 articles were included, which in the recent two decades has increased by 125%. Among the top 12 hotspots, the annual productions rapidly increased in some topics, including axonal regeneration signaling pathway, axon guidance cues, neural circuits and functional recovery, nerve conduits, and cells transplant. Comparatively, the number of studies on axon regeneration inhibitors decreased. As for the topics focusing on nerve graft and transplantation, the annual number of papers tended to be relatively stable. Nevertheless, the underlying mechanisms of axon regrowth have not been completely uncovered. A lack of notable research on the epigenetic programs and noncoding RNAs regulation was observed. The significance of cell-type-specific data has been highlighted but with limited research working on that. Functional recovery from neuropathies also needs further studies. Conclusion The last two decades witnessed tremendous progress in the field of axon regeneration. There are still a lot of challenges to be tackled in translating these technologies into clinical practice.

Neurotrophic effects of intermittent fasting, calorie restriction and exercise: a review and annotated bibliography

“…The action of Shh on neurogenesis appears to be regulated by the primary cilia of hippocampal neurons (Breunig et al, 2008). Shh also participates in axon regeneration (see the bibliometric analysis by Chou et al, 2022). The interplay of the Notch and Shh pathways, where Notch signalling potentiates the cell proliferative effect of Shh has been a recurrent finding in the recent years (Yao et al, 2016).…”

“…Wnt also participates in presynaptic differentiation (e.g., remodeling of the axon and synapse button), presynaptic and post synaptic assembly in the CNS, particularly in the hippocampus, as well as the regulation of the distribution of synapses (Salinas, 2013). Wnt also participates in axon regeneration (Chou et al, 2022). While some have mentioned that deficient Wnt signaling is linked with brain tumor genesis (Alkailani et al, 2022), others have found that increased Wnt signaling due to high glucose might be responsible for the link between diabetes and cancer (García-Giménez et al, 2014).…”

The recent two decades of traumatic brain injury: a bibliometric analysis and systematic review

“…VOSviewer and bibliometric online platforms are currently widely used, allowing the analysis of raw data downloaded from databases 6 . In particular, we used Latent Dirichlet Allocation (LDA) in our study as a deep learning method for topic modeling 7 , 8 , which is an algorithm for analyzing the hidden structure presented in a collection of documents and automatically identifying topics 9 .…”