BACKGROUND AND PURPOSE: The primary objective was to compare diffusion tensor imaging (DTI) scalar parameters of peripheral nerves between subjects with type 2 diabetes mellitus (T2DM) and those without diabetes. Secondarily, we aimed to correlate DTI scalar parameters with nerve morphometric properties. METHODS: Median, tibial, and sural nerves were harvested from 34 male cadavers (17 T2DM, 17 nondiabetic). Each nerve was divided into three segments. The initial segment was scanned using 9.4 Tesla MRI system (three-dimensional pulsed-gradient spin-echo sequence). DTI scalars were calculated from region-average diffusion-weighted signals. Second segment was optically cleared, acquired with optical projection tomography (OPT), and analyzed for morphometrical properties. Toluidine-stained sections were prepared from last segment, and axon- and myelin-related properties were evaluated. RESULTS: DTI scalar parameters of median and tibial nerves were comparable between the groups, while sural nerves of T2DM exhibited on average 41% higher mean diffusivity (MD) (p = 0.03), 38% higher radial diffusivity (RD) (p = 0.03), and 27% lower fractional anisotropy (FA) (p = 0.005). Significant differences in toluidine-evaluated parameters of sural nerves were observed between the groups, with a positive correlation between FA with fiber density (p = 0.0001) and with myelin proportion (p < 0.0001) and an inverse correlation between RD and myelin proportion (p = 0.003). OPT-measured morphometric properties did not correlate with DTI scalar parameters. CONCLUSIONS: High-field DTI shows promise as an imaging technique for detecting axonal and myelin-related changes in small sural nerves ex vivo. The reduced fiber density and decreased myelin content, which can be observed in T2DM, likely contribute to observed FA reduction and increased MD/RD.
- MeSH
- diabetes mellitus 2. typu * diagnostické zobrazování patologie MeSH
- diabetické neuropatie diagnostické zobrazování patologie MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mrtvola * MeSH
- nervus medianus diagnostické zobrazování patologie MeSH
- nervus suralis * diagnostické zobrazování patologie MeSH
- nervus tibialis diagnostické zobrazování patologie MeSH
- reprodukovatelnost výsledků MeSH
- senioři MeSH
- senzitivita a specificita MeSH
- zobrazování difuzních tenzorů * metody MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
INTRODUCTION: Nerve grafting with the sural nerve is a standard treatment method for radial nerve injury that requires another incision at the lateral ankle distal from the injured upper limb. The aim of this study was to investigate the common trunk (CTCB) of the inferior lateral brachial cutaneous nerve (ILBCN) and posterior antebrachial cutaneous nerve (PACN) as a possible donor inside the lateral intermuscular septum. MATERIALS AND METHODS: The arms and legs of 8 formalin-embalmed cadaver specimens were studied. The radial nerve, common trunk of the ILBCN and PACN, and the sural nerve were identified and measured in length and diameter. For histological examination, nerve samples from 6 fresh cadavers were harvested and processed for further axonal counting. RESULTS: The average length of the CTCB was 114.92 ± 18.9 mm. To match the diameter of the radial nerve at its proximal third, 3 cables of CTCB graft were necessary, which corresponds to a defect length of 3.8 cm. At the level of the distal third, the number of grafts was reduced to 2 with a corresponding defect length of 5.7 cm. The radial nerve contained 15162 ± 318 axons, and the CTCB comprised 3959 ± 176 axons. To match the axon count of the recipient nerve, 4 grafts of CTCB were necessary, which corresponded to a defect length of 2.8 cm. CONCLUSION: CTCB is a consistent and easily dissected cutaneous nerve branch of the radial nerve that can be used for bridging small gaps after neuroma-in-continuity in radial nerve palsy.
- MeSH
- lidé středního věku MeSH
- lidé MeSH
- mrtvola MeSH
- nervový transfer * metody MeSH
- nervus radialis * chirurgie anatomie a histologie zranění MeSH
- nervus suralis * transplantace anatomie a histologie MeSH
- senioři MeSH
- zákroky plastické chirurgie * metody MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Donor nerve selection is a crucial factor in determining clinical outcomes of facial reanimation. Although dual innervation approaches using two neurotizers have shown promise, there is a lack of evidence-based comparison in the literature. Furthermore, no animal model of dual reinnervation has yet been published. This study aimed to establish such a model and verify its technical and anatomical feasibility by performing dual-innervated reanimation approaches in Wistar rats. METHODS: Fifteen Wistar rats were divided into four experimental groups and one control group. The sural nerve was exposed and used as a cross-face nerve graft (CFNG), which was then anastomosed to the contralateral buccal branch of the facial nerve through a subcutaneous tunnel on the forehead. The CFNG, the masseteric nerve (MN), and the recipient nerve were coapted in one or two stages. The length and width of the utilized structures were measured under an operating microscope. Return of whisker motion was visually confirmed. RESULTS: Nine out of the eleven rats that underwent surgery survived the procedure. Whisker motion was observed in all experimental animals, indicating successful reinnervation. The mean duration of the surgical procedures did not differ significantly between the experimental groups, ensuring similar conditions for all groups. CONCLUSIONS: Our experimental study confirmed that the proposed reanimation model in Wistar rats is anatomically and technically feasible, with a high success rate, and shows good prospects for future experiments.
- MeSH
- faciální paralýza * chirurgie MeSH
- krysa rodu rattus MeSH
- modely nemocí na zvířatech MeSH
- nervus facialis * chirurgie fyziologie MeSH
- nervus suralis chirurgie MeSH
- potkani Wistar MeSH
- regenerace nervu * fyziologie MeSH
- vibrissae fyziologie inervace MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
CXCL12 and CXCR4 proteins and mRNAs were monitored in the dorsal root ganglia (DRGs) of lumbar (L4-L5) and cervical (C7-C8) spinal segments of naïve rats, rats subjected to sham operation, and those undergoing unilateral complete sciatic nerve transection (CSNT) on post-operation day 7 (POD7). Immunohistochemical, Western blot, and RT-PCR analyses revealed bilaterally increased levels of CXCR4 protein and mRNA in both lumbar and cervical DRG neurons after CSNT. Similarly, CXCL12 protein levels increased, and CXCL12 mRNA was upregulated primarily in lumbar DRGs ipsilateral to the nerve lesion. Intrathecal application of the CXCR4 inhibitor AMD3100 following CSNT reduced CXCL12 and CXCR4 protein levels in cervical DRG neurons, as well as the length of afferent axons regenerated distal to the ulnar nerve crush. Furthermore, treatment with the CXCR4 inhibitor decreased levels of activated Signal Transducer and Activator of Transcription 3 (STAT3), a critical transforming factor in the neuronal regeneration program. Administration of IL-6 increased CXCR4 levels, whereas the JAK2-dependent STAT3 phosphorylation inhibitor (AG490) conversely decreased CXCR4 levels. This indicates a link between the CXCL12/CXCR4 signaling axis and IL-6-induced activation of STAT3 in the sciatic nerve injury-induced pro-regenerative state of cervical DRG neurons. The role of CXCR4 signaling in the axon-promoting state of DRG neurons was confirmed through in vitro cultivation of primary sensory neurons in a medium supplemented with CXCL12, with or without AMD3100. The potential involvement of conditioned cervical DRG neurons in the induction of neuropathic pain is discussed.
- MeSH
- benzylaminy MeSH
- chemokin CXCL12 * metabolismus MeSH
- cyklamy farmakologie MeSH
- heterocyklické sloučeniny farmakologie MeSH
- interleukin-6 metabolismus MeSH
- krysa rodu rattus MeSH
- nemoci sedacího nervu metabolismus MeSH
- nervové receptory * metabolismus MeSH
- nervus ischiadicus * zranění metabolismus MeSH
- potkani Sprague-Dawley MeSH
- receptory CXCR4 * metabolismus MeSH
- regenerace nervu * MeSH
- signální transdukce * MeSH
- spinální ganglia * metabolismus MeSH
- transkripční faktor STAT3 * metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
A subpopulation of astrocytes on the brain's surface, known as subpial astrocytes, constitutes the "glia limitans superficialis" (GLS), which is an interface between the brain parenchyma and the cerebrospinal fluid (CSF) in the subpial space. Changes in connexin-43 (Cx43) and aquaporin-4 (AQP4) proteins in subpial astrocytes were examined in the medial prefrontal cortex at postoperative day 1, 3, 7, 14, and 21 after sham operation and sciatic nerve compression (SNC). In addition, we tested the altered uptake of TRITC-conjugated 3 kDa dextran by reactive subpial astrocytes. Cellular immunofluorescence (IF) detection and image analysis were used to examine changes in Cx43 and AQP4 protein levels, as well as TRITC-conjugated 3 kDa dextran, in subpial astrocytes. The intensity of Cx43-IF was significantly increased, but AQP4-IF decreased in subpial astrocytes of sham- and SNC-operated rats during all survival periods compared to naïve controls. Similarly, the uptake of 3 kDa dextran in the GLS was reduced following both sham and SNC operations. The results suggest that both sciatic nerve injury and peripheral tissue injury alone can induce changes in subpial astrocytes related to the spread of their reactivity across the cortical surface mediated by increased amounts of gap junctions. At the same time, water transport and solute uptake were impaired in subpial astrocytes.
- MeSH
- akvaporin 4 * metabolismus MeSH
- astrocyty * metabolismus MeSH
- dextrany * metabolismus MeSH
- konexin 43 * metabolismus MeSH
- krysa rodu rattus MeSH
- nervus ischiadicus * zranění metabolismus MeSH
- potkani Sprague-Dawley MeSH
- prefrontální mozková kůra * metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Charcot-Marie-Tooth disease type 1A (CMT1A) is the most common inherited peripheral neuropathy caused by a 1.5 Mb tandem duplication of chromosome 17 harbouring the PMP22 gene. This dose-dependent overexpression of PMP22 results in disrupted Schwann cell myelination of peripheral nerves. To obtain better insights into the underlying pathogenic mechanisms in CMT1A, we investigated the role of PMP22 duplication in cellular homeostasis in CMT1A mouse models and in patient-derived induced pluripotent stem cells differentiated into Schwann cell precursors (iPSC-SCPs). We performed lipidomic profiling and bulk RNA sequencing (RNA-seq) on sciatic nerves of two developing CMT1A mouse models and on CMT1A patient-derived iPSC-SCPs. For the sciatic nerves of the CMT1A mice, cholesterol and lipid metabolism was downregulated in a dose-dependent manner throughout development. For the CMT1A iPSC-SCPs, transcriptional analysis unveiled a strong suppression of genes related to autophagy and lipid metabolism. Gene ontology enrichment analysis identified disturbances in pathways related to plasma membrane components and cell receptor signalling. Lipidomic analysis confirmed the severe dysregulation in plasma membrane lipids, particularly sphingolipids, in CMT1A iPSC-SCPs. Furthermore, we identified reduced lipid raft dynamics, disturbed plasma membrane fluidity and impaired cholesterol incorporation and storage, all of which could result from altered lipid storage homeostasis in the patient-derived CMT1A iPSC-SCPs. Importantly, this phenotype could be rescued by stimulating autophagy and lipolysis. We conclude that PMP22 duplication disturbs intracellular lipid storage and leads to a more disordered plasma membrane owing to an alteration in the lipid composition, which might ultimately lead to impaired axo-glial interactions. Moreover, targeting lipid handling and metabolism could hold promise for the treatment of patients with CMT1A.
- MeSH
- buněčná membrána * metabolismus MeSH
- Charcotova-Marieova-Toothova nemoc * genetika metabolismus patologie MeSH
- duplikace genu MeSH
- homeostáza * fyziologie MeSH
- indukované pluripotentní kmenové buňky * metabolismus MeSH
- lidé MeSH
- metabolismus lipidů * fyziologie MeSH
- myelinové proteiny * metabolismus genetika MeSH
- myši MeSH
- nervus ischiadicus metabolismus MeSH
- Schwannovy buňky * metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Introduction: Isolated musculocutaneous nerve injuries occur rarely due to their anatomical location. We present our patient with a musculocutaneous nerve injury in a motorcyclist. Case: The patient was initially treated for a motorcycle accident. Further examination of the patient revealed impaired elbow flexion and numbness of the lateral forearm. Electromyography confirmed impaired function of the musculocutaneous nerve. After 3 months, the patient‘s condition did not show any improvement, neither electromyography confirmed recovery of the nerve activity, so surgical treatment was planned. In the surgical revision, neuroma-in-continuity was discovered and resected. The resulting nerve defect was 6 cm long. We provided nerve grafting using sural nerve from the right lower limb. After surgery, the patient began physical therapy and electrical stimulation. Two years later, the patient reached complete recovery of muscle strength. Conclusion: Due to the lack of improvement after a 3-month period, we proceeded with a surgical revision, which demonstrated a complete lesion of the nerve that could not heal spontaneously. Therefore, we opted for the nerve graft method and the patient regained full function of elbow flexors.
- MeSH
- dopravní nehody MeSH
- dospělí MeSH
- lidé MeSH
- motocykly MeSH
- nervový přenos MeSH
- nervus musculocutaneus * chirurgie zranění MeSH
- nervus suralis transplantace MeSH
- poranění periferního nervu * chirurgie etiologie klasifikace MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
BACKGROUND: The sural nerve is a somatosensory nerve that provides sensation to the posterolateral aspect of the lower leg and the lateral part of the ankle and foot. Due to its location and anatomical properties, it is often used as an autologous nerve graft. However, the nerve harvest can be complicated by the presence of side branches. The objective of this study was to investigate the anatomy of the sural nerve and to map its side branches. This information can be used to predict the localization of separate incisions during the stair-step incisions technique for nerve harvest, thereby reducing the risk of complications. METHODS: The study involved the dissection of 50 adult cadaveric legs (25 left and 25 right) obtained from 27 Central European cadavers. The focus of the dissection was to identify the sural nerve, small saphenous vein, and surrounding anatomical structures. Detailed measurements were taken on the side branches of the sural nerve, tributaries of the small saphenous vein, and their interrelationship. RESULTS: The average number of sural nerve side branches in a single leg was 4.2±1.9. These side branches were categorized into six groups based on their location and course: mediodistal, medioproximal, lateroproximal, laterodistal, medial perpendicular, and lateral perpendicular. Specific patterns of combination of these side branches were also identified and described. The branching point of the sural nerve was found to be 5.8±2.7 cm proximal to the lateral malleolus, whereas the small saphenous vein branching point was located more distally, 4.5 ± 2.8 cm proximal to the lateral malleolus. The highest density of sural nerve side branches was found 2.1-6.0 cm above the lateral malleolus. CONCLUSION: This study presents valuable data about the relationship between the sural nerve and the surrounding anatomical structures in the distal part of the leg, including the identification of its side branches and their relevance during nerve harvest procedures. On the basis of the most frequent locations of side branches, a three-incision-technique for nerve harvest is proposed.
- MeSH
- bérec * inervace anatomie a histologie MeSH
- disekce MeSH
- lidé středního věku MeSH
- lidé MeSH
- mrtvola * MeSH
- nervus suralis * anatomie a histologie MeSH
- odběr tkání a orgánů metody MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- vena saphena anatomie a histologie inervace MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
