Epidermal Nerve Fibers in Neuropathic Pain Model

Re-innervation in spared nerve injury (SNI) vs normal rats
Neuromics' Pain and Inflammation Research Antibodies are frequently used to help researchers find root causes of neuropathic pain. This is a fascinating study of re-innervation patterns of epidermal and dermal nerve fibers in a rat neuropathic pain model (Note: our Guinea Pig Polyclonal P2X3 Antibody was used in this study): Liron S. Durakua, Mehdi Hossaini, Barthold N. Schüttenhelm, b, Joan C. Holstege, Martijn Baas, Tom J.H. Ruigrok, Erik T. Walbeehm. Re-innervation patterns by peptidergic Substance-P, non-peptidergic P2X3, and myelinated NF-200 nerve fibers in epidermis and dermis of rats with neuropathic pain. Experimental Neurology Volume 241, March 2013, Pages 13–24. doi.org/10.1016/j.expneurol.2012.11.029.

Non-footpad area vs. footpad.The distribution pattern between the center non-footpad area and footpad is compared for the different subgroups of sensory skin fibers. For epidermal Sub P-IR and upper dermal NF-200-IR fibers there is an equal density of fibers in the center and footpad area suggesting a homogenous distribution over the foot sole of a rat. Whereas for epidermal P2X3-IR fibers there is a significant lower number of P2X3-IR fibers in the footpads as compared to the center non-footpad area, suggesting a heterogeneous distribution in the foot sole for this type of sensory fibers. N = 5 per group. Unpaired t-test. ***: p < 0,001. Scale bar: 250 μm. doi.org/10.1016/j.expneurol.2012.11.029

Illustration of the skin innervation in normal and SNI situation.Illustration showing the innervation pattern of subgroups of sensory skin fibers in the normal situation and in the SNI model 10 weeks PO. In the naïve animals the peptidergic CGRP and non-peptidergic P2X3 fibers have a lower density in the footpads as compared to the non-footpad areas, while the Substance P and NF-200 fibers have an equal distribution over the complete foot sole. In the SNI model there is a significant increase of CGRP epidermal fibers in the medial and lateral area of the foot sole and there is a complete re-innervation of the center area. In addition the footpads in the SNI model are hyper-innervated with CGRP fibers. Substance P and P2X3 and NF-200 fibers show no increased density in the uninjured medial and lateral area after 10 weeks PO. In addition, Substance P and P2X3 fibers hardly re-innervate the center area; however, the NF-200 fibers have the same density of fibers in the denervated area as in the normal situation. In the SNI model the medial, center and lateral area have all an increase in LC's, with the center area being the most prominent one. In addition the epidermis thickness of the SNI model has decreased significantly in all the three areas after 10 weeks PO.
Related Postings: http://neuromics.blogspot.com/search/label/Neuropathic%20Pain.

QCing our hMSC Derived Chondrocytes

We routinely internally test our Human Mesenchymal Stem Cells (hMSCs) and terminally differentiated cells. I would like to share the latest on our hMCS Derived Human Chondrocytes.

Msc derived human chondrocytes in culture-01-2013 from Pete Shuster
We will soon be adding QC and related images for our Osteoblasts and Endothelial Cells.

Stem Cells, Duchenne Muscular Dystrophy (DCM) & Cardiomyopathies

Transplanting Aorta-derived mesoangioblasts (ADMs) to Prevent ADM Related Cardiomyopathy-ADMs can be induced to express cardiac markers, including Nkx2.5, cardiac tropomyosin, cardiac troponin I, and -actinin, and adopt cardiomyocyte morphology. Transplantation of ADMs into the heart of mdx/utrn−/− mice prior to development of DCM prevented onset of cardiomyopathy, as measured by echocardiography, and resulted in significantly higher CD31 expression, consistent with new vessel formation. Dystrophin-positive cardiomyocytes and increased proliferation of endogenous Nestin cardiac stem cells (Neuromics' Chicken Polyclonal Nestin antibody was used as a marker to determine presence of these cells) were detected in ADM-injected heart: JU LAN CHUN, ROBERT O’BRIEN, MIN HO SONG, BLAKE F.WONDRASCH, SUZANNE E. BERRY.Injection of Vessel-Derived Stem Cells Prevents Dilated Cardiomyopathy and Promotes Angiogenesis and Endogenous Cardiac Stem Cell Proliferation in mdx/utrn−/− but Not Aged mdx Mouse Models for Duchenne Muscular Dystrophy. STEM CELLS TRANSLATIONAL MEDICINE 2013;2:000–000. http://dx.doi.org/10.5966/sctm.2012-0107.

Figure 6. Nestin and cardiac myocytes in ADM-transplanted mdx/utrn / heart. Fluorescent microscopy was used to visualize nestin interstitial and striated cells in the heart. (A): There were significantly fewer nestin interstitial stem cells in ADM-injected (dko/ADMs, n 5) mdx/utrn / heart in comparison with age-matched wild-type heart injected with saline (WT/HBSS, n 4). p values were obtained using Student’s t test. No difference was observed between WT/HBSS versus dKO/HBSS (p .0538) or dKO/HBSS versus dKO/ADMs (p .3843). (B–F): Nestin striated cells (green, indicated by white arrows) were observed in four of five mdx/utrn / hearts transplanted with ADMs. (C): A cluster of nestin striated cells (green, indicated by white arrows) and surrounding tissue containing nestin interstitial stem cells (also green, indicated by yellow arrowheads). (D–F): The same cluster of nestin cells (green) shown in (C), at higher magnification, expressed cardiac troponin I (red [E, F]). (G): Some nestin striated cells were also observed in one of four mdx/utrn / hearts injected with saline. (H): Nestin striated cells were not present in saline-injected wild-type heart. Abbreviations: ADM, aorta-derived mesoangioblast; cTpI, cardiac troponin I; DAPI, 4 ,6-diamidino-2-phenylindole; dKO, double knockout mdx/utrn / ; HBSS, Hanks’ balanced saline solution; WT, wild-type.

Conclusion: ADMs delay or prevent development of DCM in dystrophin-deficient heart, but timing of stem cell transplantation may be critical for achieving benefit with cell therapy in DMDcardiac muscle.
Stem Cell Research Reagents.

Shiny, New GF nanoparticle labeled hMSCs

Human Mesenchymal Stem Cells-Green Fluorescent Nanoparticle-labeled-These cells are generated by chemical transfection of CdSe/ZnS nanoparticles, 100 nm in diameter and show a strong fluorescent signal (Excitation maximum= 515 nm; Emission maximum= 520-550 nm) detectable by standard FITC filters.

Image: FITC analysis of cells during fourth passage following transfection. Image obtaining using FITC filter on Olympus CKX41 microscope at 200 X equipped with a Retiga 2000 digital camera and Q-Capture software program. Scale bar is 25 micrometers. Fluorescent nanoparticles are less prevalent within the cytoplasm than earlier passages. Technical Information & Data.

They retain GFNP labeling through 3+ passages and can be differentiation into chondrogenic, adipogenic or osteogenic lineages. Excellent for regeneration, toxicity and related studies. Technical Information & Data.

Image: Osteogenic differentiation of GF nanoparticle-labeled MSCs. Image obtaining using phase contrast Olympus CKX41 microscope at 100 X equipped with a Retiga 2000 digital camera and Q-Capture Pro software program. Scale bar is 25 micrometers. Note the presence of mineral deposits indicating differentiation into osteoblasts. Chondrogenic and adipogenic differentiation was also apparent.

• All Stem Cell Research Reagents.

Pain and the Interplay Between P2Y Receptors with P2X3

P2Y2-P2X3 crosstalk in DRG neurons

Alfredo Ribeiro-da-Silva and his team use our Purinergic Receptor Antibodies to the study role of their expression in Nociceptive and Neuropathic Pain. They referenced their use in 8 publications.

Based on their research, they suspect changes in P2X3 function under pathological conditions are more complex than simple up- or down-regulation of expression at the protein level. This would have profound implications for the dicovery of drugs that target P2X3 expression levels: Gary Mo, Jennifer C. Peleshok, Chang-Qing Cao, Alfredo Ribeiro-da-Silva and Philippe Séguéla. Control of P2X3 channel function by metabotropic P2Y2 UTP receptors in primary sensory neurons. Molecular Pharmacology Fast Forward. Published on December 18, 2012 as doi:10.1124/mol.112.082099.

Images: P2X3 and P2Y2 receptors are co-expressed in rat DRG sensory neurons.(A) DRG sections labeled for P2Y2 (green) and P2X3 (red) and merged (yellow). P2Y2 immunoreactivity is broadly distributed in small-diameter neuronal somata and co-localized with P2X3 (arrows). P2Y2 immunoreactivity can be detected in cells negative for P2X3 (arrow heads). (B) P2Y2 (green) and P2X3 (red) are also colocalized (yellow) in peripheral nerve fibers.

The two receptors were found to be colocalized both in cell bodies and nerve fibers, indicating co-trafficking to peripheral and central terminals. The immunolocalization evidence presented here provides valuable information on the physiological relevance of crosstalks between ionotropic and metabotropic ATP receptors in sensory pathways, yet much work is still needed to fully comprehend the role of nucleotide signaling in pain, especially in pathological conditions. Changes in P2Y2 receptor expression in response to inflammation have been documented (Malin et al., 2008), therefore it will be worth investigating the functional impact of P2Y2-P2X3 interactions on ATP signaling under chronic pain conditions.

I will keep you posted on any new developments.