Selective Expression of a SNARE-Cleaving Protease in Peripheral Sensory Neurons Attenuates Pain-Related Gene Transcription and Neuropeptide Release

Neural and Inflammatory Interactions in Wound Healing

ABSTRACT

The skin is an intricate network of both neurons and immunocytes, where emerging evidence has indicated that the regulation of neural-inflammatory processes may play a crucial role in mediating wound healing. Disease associated abnormal immunological dysfunction and peripheral neuropathy are implicated in the pathogenesis of wound healing impairment. However, the mechanisms through which neural-inflammatory interactions modulate wound healing remain ambiguous. Understanding the underlying mechanisms may provide novel insights to develop therapeutic devices, which could manipulate neural-inflammatory crosstalk to aid wound healing. This review aims to comprehensively illustrate the neural-inflammatory interactions during different stages of the repair process. Numerous mediators including neuropeptides secreted by the sensory and autonomic nerve fibers and cytokines produced by immunocytes play an essential part during the distinct phases of wound healing.

Age-associated changes in lineage composition of the enteric nervous system regulate gut health and disease

The enteric nervous system (ENS), a collection of neural cells contained in the wall of the gut, is of fundamental importance to gastrointestinal and systemic health. According to the prevailing paradigm, the ENS arises from progenitor cells migrating from the neural crest and remains largely unchanged thereafter. Here, we show that the lineage composition of maturing ENS changes with time, with a decline in the canonical lineage of neural-crest derived neurons and their replacement by a newly identified lineage of mesoderm-derived neurons. Single cell transcriptomics and immunochemical approaches establish a distinct expression profile of mesoderm-derived neurons. The dynamic balance between the proportions of neurons from these two different lineages in the post-natal gut is dependent on the availability of their respective trophic signals, GDNF-RET and HGF-MET. With increasing age, the mesoderm-derived neurons become the dominant form of neurons in the ENS, a change associated with significant functional effects on intestinal motility which can be reversed by GDNF supplementation. Transcriptomic analyses of human gut tissues show reduced GDNF-RET signaling in patients with intestinal dysmotility which is associated with reduction in neural crest-derived neuronal markers and concomitant increase in transcriptional patterns specific to mesoderm-derived neurons. Normal intestinal function in the adult gastrointestinal tract therefore appears to require an optimal balance between these two distinct lineages within the ENS.

Advances in Clostridial and Related Neurotoxins

The huge advances in genomics and molecular biology in the past two decades have made now an exciting time to study bacterial toxins, in particular, the most potent bacterial toxin known to humankind, botulinum neurotoxins (BoNTs) [...].