Arthritic Pain, Nerve Sprouting and Neuroma Formation

Our friends, Drs Mantyh and Jimenez Andrade, have published important findings on the potential root cuases of age related Arthritic Pain: Juan M Jimenez-Andrade and Patrick W Mantyh. Sensory and sympathetic nerve fibers undergo sprouting and neuroma formation in the painful arthritic joint of geriatric mice. Note: our Chicken Polyclonal NF200 Antibody was used to label primary afferent sensory nerve fibers.

Overview: Introduction: Although the prevalence of arthritis dramatically increases with age, the great majority of preclinical studies concerning the mechanisms that drive arthritic joint pain have been performed in young animals. One mechanism hypothesized to contribute to arthritic pain is ectopic nerve sprouting; however, neuroplasticity is generally thought to be greater in young versus old nerves. Here we explore whether sensory and sympathetic nerve fibers can undergo a significant ectopic nerve remodeling in the painful arthritic knee joint of geriatric mice.

In other words, there is a clear root reason that the pain arthritis sufferers experience increases overtime. Here's some related data. Notice the increase in labeled nerves:

Images. Sensory nerve fiber sprouting and formation of neuroma-like structures in the painful geriatric arthritic knee joint. Schematic of a frontal view of a cross-sectioned mouse knee joint (A). The red square illustrates the synovial region from which the confocal images were obtained. Representative confocal images of calcitonin gene-related peptide (CGRP+), neurofilament 200 kDa (NF200+) sensory nerve fibers (yellow/orange) and growth associated protein (GAP43; marker of fibers undergo regeneration, yellow/orange) and DAPI labeled nuclei (blue) in knee joint sections (20 μm thick) of vehicle-injected (B,D,F) and CFA-injected (C,E,G ) mice. In vehicle-injected mice, a low level, regular pattern of innervation by CGRP+ and NF200+ fibers is observed in the synovial space of the knee joint. Twenty-eight days following the initial CFA injection, a significant number of CGRP+ and NF200+ nerve fibers have sprouted and have a disorganized appearance as compared to vehicle-injected mice. Note that, CGRP+ and NF200+ sprouted nerve fibers are localized in the synovium and are not observed in the meniscus of the joint. Furthermore, there was formation of neuroma-like structures in the synovium of the geriatric mice injected with CFA (G).

Related Reagents: Neuronal-Glial Markers-Astrocytes, Glia, Microglia, Olidogodendrocytes, Progenitors and Schwann Cell Markers.