Rheumatoid arthritis in review: Clinical, anatomical, cellular and molecular points of view

Monocyte chemoattractant protein‑1 promotes the proliferation, migration and differentiation potential of fibroblast‑like synoviocytes via the PI3K/P38 cellular signaling pathway

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation of the joints and joint destruction. Monocyte chemoattractant protein 1 (MCP‑1) is highly expressed in the joints of patients suffering from RA. The present study aimed to evaluate the effects of MCP‑1 on the phenotype of fibroblast‑like synoviocytes (FLSs) and their differentiation potential towards vascular endothelial cells. The expression of MCP‑1 in collagen‑induced arthritis (CIA) rats was investigated by PCR, ELISA and immunohistology. Cell proliferation induced by MCP‑1 was measured using a Cell Counting Kit‑8 (CCK‑8) and 5‑Bromo‑2‑deoxyuridine ELISA assay. In addition, the effects of MCP‑1 on the migration of FLSs was examined using a Transwell assay. Activation of PI3K and P38 were investigated by western blotting following MCP‑1 treatment. The vascular endothelial cell markers, tumor necrosis factor alpha (TNF‑α) and interleukin‑1 beta (IL‑β), were also examined by western blotting. LY294002 [PI3K inhibitor, (LY)] and SB203580 [P38 inhibitor, (SB)] were used to examine the proliferative and pro‑differentiation effect of PI3K and P38. The present findings showed that the expression level of MCP‑1 in the synovium of CIA rats was significantly higher compared with controls. The present in vitro study suggested that MCP‑1 increased the FLSs cell numbers with a maximal effect at 200 ng/ml, and induced the maximal phosphorylation of PI3K at 15 min and P38 at 30 min. In addition, MCP‑1 stimulation significantly increased the migration of FLSs. Furthermore, MCP‑1‑induced the expression of vascular endothelial growth factor and CD31 in FLSs. Suppression of PI3K and P38 was found to reduce MCP‑1 induced FLSs proliferation and migration, and decreased the expression levels of angiogenesis markers increased following MCP‑1 treatment. MCP‑1 was also found to increase the expression levels of both TNF‑α and IL‑β. Therefore, MCP‑1 could promote the proliferation and migration of FLSs, and was found to increase the expression levels of various angiogenesis markers via PI3K/P38, suggesting a role for this pathway in synovium hyperplasia in RA.

LncRNA MEG3 inhibits rheumatoid arthritis through miR-141 and inactivation of AKT/mTOR signalling pathway

Rheumatoid arthritis (RA) is a chronic inflammation mediated by autoimmune responses. MEG3, a kind of long noncoding RNA (lncRNA), participates in cell proliferation in cancer tissues. However, the correlation between MEG3 and RA is yet unclear. Therefore, to clarify how MEG3 works in RA, we performed a series of experiments using RA samples. We found that MEG3 was downregulated in the fibroblast-like synoviocytes of RA patients (RA-FLS), in comparison with healthy subjects. MEG3 was also down-regulated evidently in lipopolysaccharide (LPS)-treated chondrocyte. As part of our experiments, MEG3 was overexpressed in chondrocyte by transfection with lentivirus containing sequences encoding MEG3. In addition, in presence of LPS, reductions were identified not only in the cell proliferation, but also in the generation of interleukin-23 (IL-23), which, however were reversed in the lentivirus (containing MEG3-encoding sequences)-transfected chondrocytes. Up-regulated MEG3 resulted in an increase the level of Ki67. Moreover, MEG3 was negatively correlated with miR-141, and miR-141 was up-regulated in LPS-treated chondrocyte. Inhibitory effects of MEG3 overexpression, mentioned above, were partially abolished by overexpressed miR-141. Further, animal experiment also showed the inhibitory effect of MEG3 in overexpression on the AKT/mTOR signaling pathway. In-vivoexperiments also showed that cell proliferation was facilitated by MEG3 overexpression with inhibited inflammation. In summary, the protective role of MEG3 in RA was proved to be exerted by the increase in the rate of proliferation, which might correlate to the regulatory role of miR-141 and AKT/mTOR signal pathway, suggesting that MEG3 holds great promise as a therapeutic strategy for RA.

Th17 Cells and the IL-23/IL-17 Axis in the Pathogenesis of Periodontitis and Immune-Mediated Inflammatory Diseases

Innate immunity represents the semi-specific first line of defense and provides the initial host response to tissue injury, trauma, and pathogens. Innate immunity activates the adaptive immunity, and both act highly regulated together to establish and maintain tissue homeostasis. Any dysregulation of this interaction can result in chronic inflammation and autoimmunity and is thought to be a major underlying cause in the initiation and progression of highly prevalent immune-mediated inflammatory diseases (IMIDs) such as psoriasis, rheumatoid arthritis, inflammatory bowel diseases among others, and periodontitis. Th1 and Th2 cells of the adaptive immune system are the major players in the pathogenesis of IMIDs. In addition, Th17 cells, their key cytokine IL-17, and IL-23 seem to play pivotal roles. This review aims to provide an overview of the current knowledge about the differentiation of Th17 cells and the role of the IL-17/IL-23 axis in the pathogenesis of IMIDs. Moreover, it aims to review the association of these IMIDs with periodontitis and briefly discusses the therapeutic potential of agents that modulate the IL-17/IL-23 axis.

Internal Morphology of the Odontoid Process: Anatomic and Imaging Study with Application to C2 Fractures

OBJECTIVE

Fracture of the odontoid process is a critical injury to diagnose and often treat. The aim of this anatomic study was to present a comprehensive understanding of this part of the C2 vertebra.

METHODS

We used 20 C2 vertebrae. Samples underwent imaging (computed tomography [CT] with and without three-dimensional reconstruction, micro-CT, 1.5T magnetic resonance imaging) and sagittal and coronal sectioning using a bone saw. Sectioned specimens were imaged under a digital handheld microscope, and transillumination of the bone was used to highlight its internal trabecular pattern. Three samples underwent infusion of the odontoid process with a hardening substance and were then decalcified.

RESULTS

Internal trabecular patterns of the odontoid process of all specimens were discernible. In sagittal and coronal sections, trabecular patterns were highlighted with transillumination, but the patterns were much clearer using the digital microscope. Magnetic resonance imaging and CT provided the least detail of the imaging methods, but the trabecular patterns could be identified. Three-dimensional reconstruction of CT data was the preferred imaging method over magnetic resonance imaging and CT without three-dimensional reconstruction. The most distinct trabecular and cortical patterns were seen using micro-CT. Osteoporosis was seen in 2 specimens (10%). Five specimens (25%) were found to have a subdental synchondrosis. For most specimens, the trabeculae were found throughout the odontoid process.

CONCLUSIONS

Improved knowledge of the anatomy, structural composition, and variations within the C2 vertebra may allow for better treatment options and patient care.

Gerber's Ligament-A Forgotten Structure of the Craniocervical Junction

BACKGROUND

Ligaments of the craniocervical junction play a critical role in stabilizing this region. Gerber's ligament has more or less been forgotten and, to our knowledge, never studied.

METHODS

Dissection of the craniocervical junction was performed in 15 fresh frozen cadavers. In the prone position, the posterior elements of the upper cervical vertebrae and occiput were removed. After removing the contents of the spinal canal and posterior cranial fossa, the dura mater and tectorial membrane were reflected. The superior band of the cruciform ligament was reflected. When Gerber's ligament was identified, its attachments and morphometry were recorded. Lastly, Gerber's ligament was observed while range of motion of the craniocervical junction was performed.

RESULTS

Gerber's ligament was identified in 7 specimens (46.7%). This structure arose anteriorly from the junction of the superior band and transverse part of the cruciform ligament. Gerber's ligament was always found to be just deep to the superior band of the cruciform ligament but traveled more anteriorly to attach onto the posterior aspect of the dens approaching, but not attaching onto, its apex. Mean length was 11 mm, and mean width was 7 mm. Thickness of the ligament was 0.5-1.1 mm. The ligament was found to become taut with minimal rotation of the atlantoaxial joint and extension of the craniocervical junction.

CONCLUSIONS

A good understanding of all ligaments of the craniocervical junction is important to surgeons and physicians treating patients with injury to the upper cervical spine.

Perioperative Management of the Rheumatoid Patient

Rheumatoid arthritis is a complex disease state with multiple associated comorbidities. Perioperative evaluation of the rheumatoid patient from a multidisciplinary approach is necessary to achieve favorable outcomes. A complete history and physical, laboratory, cervical, cardiovascular, pulmonary, and medication assessment before surgery should be performed. Educating the patient on potential complications, such as wound dehiscence, infection, and venous thromboembolism, as well as general postoperative expectations, is essential when evaluating the rheumatoid patient for surgery.

Superficial anterior atlanto-occipital ligament: Anatomy of a forgotten structure with relevance to craniocervical stability

Introduction

The superficial anterior atlanto-occipital ligament (SAAOL) is a narrowband located anterior to the anterior atlanto-occipital membrane. Nearly forgotten, it has not been well described in older anatomical textbooks and is missing in the current anatomical literature. As all of the binding structures of the craniocervical junction (CCJ) are important in maintaining stability, this study aims to clarify the anatomy and potential function of the SAAOL.

Materials and Methods

The CCJ from ten fresh-frozen cadavers was studied. These specimens were derived from three males and seven females, and the age at death ranged from 57 to 91 years (mean, 79.8 years). The length, width, and thickness of the SAAOL were measured. In five specimens, the force to failure was recorded.

Results

The SAAOL was found between the anterior tubercle of the atlas and the occiput and located as central thick fibers in front of the anterior atlanto-occipital membrane in 9 (90%) specimens. In one specimen, the vertical band to the occipital bone did not attach to the anterior tubercle of the atlas, but extended to the anterior aspect of the axis. The mean length, width, and thickness of the SAAOL were 19.8, 6.2, and 0.6 mm, respectively. The force to failure for the ligament was 38.8 N.

Conclusion

The SAAOL was a constant structure of the anterior atlanto-occipital joint. This ligament seems to be a secondary stabilizer of the CCJ by limiting the extension of CCJ. Knowledge of this ligament may help in further understanding of craniocervical stability.

The clinical anatomy of fibromyalgia

Fibromyalgia is a disorder characterized by pain and a spectrum of psychological comorbidities, rendering treatment difficult, and often a financial burden. Findings regarding diagnosis, prevalence, comorbidities, and potential pathophysiological links are discussed herein. Fibromyalgia is a complex disorder and there are specific criteria that patients must meet for diagnosis, including scores on fibromyalgia questionnaires, commonalities of age, gender, menopause status, sleep disturbances, and mood symptoms. The close relationship between fibromyalgia and other chronic disorders should alert the physician to explore for comorbid illnesses. In this review of the clinical anatomy of fibromyalgia, we review new studies that could be significant for the current use of clinical interventions for patients with symptoms. Using standard search engines, the clinical anatomy of fibromyalgia is investigated and many related studies are mentioned herein. Fibromyalgia is considered a prototypical central chronic pain syndrome and is associated with widespread pain that fluctuates spontaneously. There is also substantial lifetime psychiatric comorbidity in individuals with fibromyalgia, resulting in a low health-related quality of life. These results have important clinical and theoretical implications, including the possibility that fibromyalgia could share underlying pathophysiological links with some psychiatric disorders. This reveals that patients with fibromyalgia have findings compatible with tissue injury pain, the pain mechanisms involving both the primary afferent neuron and the nociceptive systems in the central nervous system. (1) There is a relationship between fibromyalgia and chronic disorders. This should alert the physician to explore for comorbid illnesses. (2) There is substantial lifetime psychiatric comorbidity resulting in a low health-related quality of life. (3) Patients with fibromyalgia have findings compatible with tissue injury pain Clin. Anat. 31:387-391, 2018. © 2018 Wiley Periodicals, Inc.