**5. Final considerations**

According to the available evidence, ageing constitutes a vulnerable stage for cell fate mainly because of the delicate balance of several molecular conditions. Under these conditions, any additional challenge to any homeostatic system can trigger the breakdown of such equilibrium, leading to the manifestation of pathological processes, such as neurodegenerative disorders. AD and PD, the first and second most prevalent age-related diseases, can be favoured by a spontaneous imbalance in the homeostatic system and, once initiated, further contribute to increasing the homeostatic imbalance. A complex network of molecular alterations, organelle dysfunction and cellular signalling, among others, increases the difficulty of properly addressing the cloudy edge between healthy ageing, pathological ageing and age-related disorders. However, neuroinflammation and the perpetuation of a chronic pro-inflammatory status have emerged as a central axis connecting all these conditions. Although our knowledge regarding the inflammatory process has increased during years, the intricate molecular network that drives the final inflammatory response is still incomplete. In this regard, Wnt signalling, which has been demonstrated to be a relevant player in ageing and age-related disorders, such as AD and PD, should also be considered among the potentially relevant molecular pathways that could be involved in the modulation of the inflammatory process. Moreover, the still limited information regarding the Wnt-inflammatory response crosstalk already suggests interesting potentialities of an anti-inflammatory intervention based on the modulation of Wnt signalling. On the other hand, based on our research and considering the age-related changes in Wnt activity, it is possible to suggest that Wnt signalling can also be an interesting target to support physiological ageing.

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