Raynaud’s Phenomenon and Vascular Disease in Systemic Sclerosis

Neurogenic Appendicitis: A Reappraisal of the Clinicopathological Features and Pathogenesis

In 1921; Masson and Maresch first coined the term “neurogenic appendicitis (NA)” to describe “neuroma-like” lesions in the appendix. To date, our knowledge about NA is limited; therefore, we conducted a comprehensive analysis of the literature (1921 to 2020) to examine the clinicopathological features of NA. We also addressed the pathophysiology of acute abdominal pain and fibrosis in this entity. We performed a meta-analysis study by searching the PubMed database, using several keywords, such as: “appendix,” “neurogenic,” “obliterative,” “neuroma,” “fibrous obliteration,” “appendicopathy,” and “appendicitis.” Our study revealed that patients with NA usually present clinically with features of acute appendicitis, bud2t they have grossly unremarkable appendices. Histologically, the central appendiceal neuroma was the most common histological variant of NA, followed by the submucosal and intramucosal variants. To conclude, NA represents a form of neuroinflammation. The possibility of NA should be considered in patients with clinical features of acute appendicitis who intraoperatively show a grossly unremarkable appendix. Neuroinflammation and neuropeptides play roles in the development of pain and fibrosis in NA.

Neurosonological and cognitive screening for evaluation of systemic sclerosis patients

OBJECTIVE

Assessment of cerebrovascular hemodynamics, third ventricle diameter (as a proxy of brain atrophy) by transcranial sonography (TCS), and screening of cognitive performance by the Symbol Digit Modalities Test (SDMT) in systemic sclerosis (SSc) patients.

METHODS

A total of 38 SSc patients recruited from the outpatient clinic of the Rheumatology Department, Kasr Alainy Hospital, Cairo University, and 51, age- and sex-matched, healthy controls were included in the study. TCS was used to assess the mean flow velocity (MFV), pulsatility index (PI) of the anterior, middle, and posterior cerebral arteries bilaterally, and to measure the third ventricle diameter as a proxy of brain atrophy. Cognitive impairment was screened using the SDMT. p values < 0.05 were considered statistically significant.

RESULTS

There was no significant difference between SSc patients and controls regarding either PI or MFV of the anterior, middle, and posterior cerebral arteries; also, there was no difference regarding the third ventricle diameter; however, limited SSc patients showed a significant increase in the PI of PCA and MFV of ACA as compared with diffuse SSc patients (p = 0.005, 0.004). There was a significant difference between SSc patients and controls regarding the SDMT (p = 0.016).

CONCLUSION

There is an evidence of increased cerebral vascular tone and resistance in limited SSc patients compared with diffuse SSc subgroup, without evidence of cerebral atrophy, suggesting early cerebrovascular affection even in asymptomatic limited SSc patients. There was also an evidence of cognitive impairment in SSc patients.

Rituximab for refractory digital infarcts and ulcers in systemic sclerosis

Systemic sclerosis is an uncommon connective tissue disease characterised by excessive deposition of collagen and vasculopathy which affects the skin and multiple internal organs. It is associated with autoimmunity, inflammation, vasculopathy and fibrosis. Managing Raynaud's phenonemon, digital infarcts and ulcers in systemic sclerosis patients is often a challenge particularly among rheumatologists. We report a case of systemic sclerosis patient with refractory digital infarcts and ulcers responded successfully with rituximab.

Insights into the pathogenesis of systemic sclerosis based on the gene expression profile of progenitor-derived endothelial cells

OBJECTIVE

To determine the gene expression profile of endothelial cells derived from the endothelial progenitor cells (EPCs) of patients with systemic sclerosis (SSc).

METHODS

Microarray experiments were performed on Affymetrix GeneChip Human Exon 1.0 ST Arrays in unstimulated and hypoxia-stimulated EPC-derived cells from patients with SSc and control subjects. Followup of the raised hypotheses was performed ex vivo by immunohistochemical analysis of skin tissue.

RESULTS

Signals from 92 probe sets and 188 probe sets were different in unstimulated and hypoxia-stimulated cells, respectively, from patients with SSc compared with controls. Within the largest groups of genes related to cell-cell interaction and vascular remodeling, down-regulation of tumor necrosis factor ligand superfamily member 10 (TNFSF10) and homeobox A9 (HOX-A9) was confirmed by real-time polymerase chain reaction and Western blots in EPC-derived cells and by immunohistochemistry in SSc skin tissue. Signals from 221 and 307 probe sets were different in unstimulated and hypoxia-stimulated cells, respectively, from patients with diffuse cutaneous SSc compared with patients with limited cutaneous SSc. Within the largest group of genes related to the inflammatory response, differential expression of TNFα-induced protein 3 and prostaglandin-endoperoxide synthase 2 was observed in EPC-derived cells and skin tissue from patients with SSc.

CONCLUSION

Our data revealed important gene expression changes in EPC-derived endothelial cells from patients with SSc, characterized by a proadhesive, proinflammatory, and activated phenotype. Differential expression in lesional SSc skin tissue of new targets, such as TNF family members and HOX-A9, may contribute to the pathogenesis of SSc and deserves more in-depth exploration.

Serotonin paracrine signaling in tissue fibrosis

The molecule serotonin (5-hydroxytryptamine or 5-HT) is involved in numerous biological processes both inside and outside of the central nervous system. 5-HT signals through 5-HT receptors and it is the diversity of these receptors and their subtypes that give rise to the varied physiological responses. It is clear that platelet derived serotonin is critical for normal wound healing in multiple organs including, liver, lung heart and skin. 5-HT stimulates both vasoconstriction and vasodilation, influences inflammatory responses and promotes formation of a temporary scar which acts as a scaffold for normal tissue to be restored. However, in situations of chronic injury or damage 5-HT signaling can have deleterious effects and promote aberrant wound healing resulting in tissue fibrosis and impaired organ regeneration. This review highlights the diverse actions of serotonin signaling in the pathogenesis of fibrotic disease and explores how modulating the activity of specific 5-HT receptors, in particular the 5-HT2 subclass could have the potential to limit fibrosis and restore tissue regeneration. This article is part of a Special Issue entitled: Fibrosis: Translation of basic research to human disease.

Increased circulating fibrinogen-like protein 2 in patients with systemic sclerosis

Fibrinogen-like protein 2 (FGL2), a member of the fibrinogen-related superfamily of proteins, is expressed on the surface of macrophages, T cells, and endothelial cells and directly cleaves prothrombin to thrombin. The aim of this study is to determine the serum FGL2 level and its association with clinical parameters in patients with systemic sclerosis (SSc). Serum FGL2 level was examined by enzyme-linked immunosorbent assay in 61 patients with SSc, 24 patients with systemic lupus erythematosus, and 24 healthy individuals. In a retrospective longitudinal study, sera from 13 patients with SSc were analyzed. The serum FGL2 level was increased in patients with SSc compared with healthy individuals (P < 0.001) and patients with systemic lupus erythematosus (P < 0.01). Among patients with SSc, there were no differences in serum FGL2 level between limited cutaneous SSc and diffuse cutaneous SSc. In the longitudinal study, the FGL2 level was generally unchanged at follow-up. The results show that the serum FGL2 level was increased in patients with SSc but not in patients with systemic lupus erythematosus or healthy individuals. Therefore, FGL2 possibly contribute to the development of SSc.

Clinical significance of circulating platelet-activating factor acetylhydrolase levels in systemic sclerosis

Platelet-activating factor acetylhydrolase (PAF-AH) has been demonstrated to be one of anti-inflammatory and anti-apoptotic factors, suggesting the potential to be involved in the development of systemic sclerosis (SSc). The aim of this study is to determine serum PAF-AH levels and their clinical associations in patients with SSc. Serum PAF-AH levels were examined by enzyme-linked immunosorbent assay in 57 patients with SSc and 24 healthy individuals. Serum PAF-AH levels were significantly elevated in SSc patients (130.4 ± 69.5 ng/ml) compared with healthy individuals (81.6 ± 34.8 ng/ml; P < 0.001). Among SSc patients, there were no differences in serum PAF-AH levels between those with diffuse cutaneous SSc (135.5 ± 79.3 ng/ml; n = 29) and those with limited cutaneous SSc (125.1 ± 58.6 ng/ml; n = 28). Patients with SSc who had raised PAF-AH levels less often had digital ulcers and arthritis/arthralgias than those with normal PAF-AH levels. The results show that serum PAF-AH levels were increased in patients with SSc and associated with a lower frequency of pitting scars/digital ulcers and arthritis/arthralgias. PAF-AH could be a protective factor against the development of digital ulcers and arthritis/arthralgia in this disease and as such would be a useful serological marker for disease severity.

Brachial artery endothelial-dependent flow-mediated dilation identifies early-stage endothelial dysfunction in systemic sclerosis and correlates with nailfold microvascular impairment

OBJECTIVE

To assess possible correlations between endothelial-dependent flow-mediated dilation (FMD) of the brachial artery and nailfold videocapillaroscopy (NVC) in patients with systemic sclerosis (SSc). Evidence has shown that vascular impairment in SSc may be a sign of endothelial dysfunction involving both microvascular and macrovascular systems, although the pathological mechanisms of the dysfunction are poorly understood.

METHODS

Forty-three consecutive patients (mean age 51 +/- 11 yrs) with SSc were studied. Thirty patients had limited cutaneous SSc, 13 had diffuse cutaneous SSc. Twenty-seven healthy subjects (mean age 48 +/- 8 yrs) were recruited as controls. Ultrasound assessment of FMD was performed on all subjects in order to evaluate macrovascular function. Patients were divided into 3 patterns of microvascular damage on the basis of NVC (early, active, and late), and the microangiopathy evolution score was calculated, as reported elsewhere.

RESULTS

FMD was significantly reduced in patients with SSc compared to healthy subjects [median 8.0% (3.0%-9.0%) vs 15.0% (12.0%-16.0%), respectively; p < 0.0001]. Patients with an early pattern of microangiopathy showed reduced FMD values compared to controls (p = 0.0001). FMD was significantly reduced in patients with SSc who had the late NVC pattern of microangiopathy compared to active and early patterns (p = 0.003 and p = 0.001, respectively). FMD was inversely correlated with the microvascular damage rate in patients with SSc (p < 0.0001).

CONCLUSION

We demonstrated the simultaneous presence of macrovascular and microvascular impairment in patients with SSc, which was already present in the early phase of the vascular disease.

Association of hypoxia-inducible factor 1A (HIF1A) gene polymorphisms with systemic sclerosis in a French European Caucasian population

OBJECTIVE

Systemic sclerosis (SSc) is a connective tissue disease characterized by generalized microangiopathy leading to chronic hypoxia. The aim of this study was to determine whether polymorphisms of the hypoxia-inducible factor 1A gene (HIF1A) affects susceptibility to SSc in a large French European Caucasian population.

METHODS

A case-control study was performed in 659 SSc patients and 511 healthy matched controls. Three tag single nucleotide polymorphisms (SNPs) of the HIF1A gene (rs12434438 A/G, rs1957757 C/T, and rs11549465 C/T) were genotyped allowing whole gene coverage according to HapMap data.

RESULTS

The frequency of genotypes carrying at least one G allele (A/G and/or GG) of the rs12434438 SNP was significantly higher in SSc patients than in controls [p(corr) = 0.018, odds ratio (OR) 1.44, 95% confidence interval (CI) 1.08-1.91]. Regarding SSc subgroup analyses, the heterozygous genotype A/G was associated with SSc (p(corr) = 0.012, OR 1.47, 95% CI 1.13-1.9), with the limited cutaneous form of SSc (p(corr) = 0.04, OR 1.43, 95% CI 1.08-1.91), and with positive anti-centromere antibodies (ACA; p(corr) = 0.016, OR 1.61, 95% CI 1.16-2.23). No association was detected for the remaining two HIF1A SNPs tested. Haplotype analyses did not detect any association with SSc.

CONCLUSIONS

We observed an association between the HIF1A gene and SSc in a European Caucasian population, supporting a role for HIF1 in the pathophysiology of SSc.

Skin ulcers in systemic sclerosis: determinants of presence and predictive factors of healing

BACKGROUND

Skin ulcers are common vascular complications of systemic sclerosis (SSc).

OBJECTIVE

The aim of the study was to identify clinical, biologic, and imaging parameters that constitute risk factors for the occurrence and persistence of skin ulcers.

METHODS

One hundred thirty Italian SSc patients were examined at entry and after 20 months of follow-up.

RESULTS

The diffuse SSc phenotype with avascular areas on capillaroscopy, thrombophilia, and systemic inflammation as defined by interleukin 6 plasma levels, represented the major risk factors for ulcer development. Infection was associated with a risk of poor or no healing, and cardiopulmonary involvement was a major comorbid factor in patients with ulcers. The presence of infection and avascular areas represented the main determinants for ulcer healing.

LIMITATIONS

Our data should be confirmed with a longer follow-up period since skin ulcers represent a frequent vascular complication in scleroderma patients.

CONCLUSION

Aggressive therapies aiming at improving angiogenesis and controlling infection and the course of the disease appear to be crucial to obtain ulcer healing.

Angiogenesis in systemic sclerosis: impaired expression of vascular endothelial growth factor receptor 1 in endothelial progenitor-derived cells under hypoxic conditions

OBJECTIVE

To assess angiogenesis and explore the expression and regulation of vascular endothelial growth factor (VEGF), VEGF receptor 1 (VEGFR-1), and VEGFR-2, the leading mediators of angiogenesis, in SSc patients and controls.

METHODS

Late-outgrowth endothelial progenitor cells (EPCs), isolated from the peripheral blood of systemic sclerosis (SSc) patients and controls, and human umbilical vein endothelial cells (HUVECs) were assessed under normal and hypoxic conditions. Genomic background was evaluated in a large case-control study (including 659 patients with SSc and 511 controls) using tag single-nucleotide polymorphisms on VEGFR1 and VEGFR2 genes.

RESULTS

EPCs from SSc patients had the phenotype of genuine endothelial cells and displayed in vitro angiogenic properties similar to those of HUVECs and control EPCs under basal conditions, as determined by flow cytometry, tube formation, and migration assay. However, after 6 hours of hypoxic exposure, EPCs from SSc patients exhibited lower induced expression of VEGFR-1 at the messenger RNA and protein levels, but similar VEGF and VEGFR-2 expression, compared with HUVECs or EPCs from healthy controls. There was no evidence of defective expression of hypoxia-inducible factor 1alpha. These results were supported by the lower serum levels of soluble VEGFR-1 found in SSc patients (n = 187) compared with healthy controls (n = 48) (mean +/- SD 163.7 +/- 98.5 versus 210.4 +/- 109.5 pg/ml; P = 0.0042). These abnormalities did not seem to be related to genomic background.

CONCLUSION

Our findings shed new light on the possible role of VEGFR-1 in the main vascular disturbances that occur in SSc and lead to more severe disease.

Hypoxia-induced increase in the production of extracellular matrix proteins in systemic sclerosis

OBJECTIVE

Insufficient angiogenesis with tissue ischemia and accumulation of extracellular matrix are hallmarks of systemic sclerosis (SSc). Based on the severely decreased oxygen levels in the skin of patients with SSc, we aimed to investigate the role of hypoxia in the pathogenesis of SSc.

METHODS

Subtractive hybridization was used to compare gene expression in dermal fibroblasts under hypoxic and normoxic conditions. Dermal fibroblasts were further characterized by exposure to different concentrations of oxygen and for different time periods as well as by interference with hypoxia-inducible factor 1alpha (HIF-1alpha). The systemic normobaric hypoxia model in mice was used for in vivo analyses.

RESULTS

Several extracellular matrix proteins and genes involved in extracellular matrix turnover, such as thrombospondin 1, proalpha2(I) collagen, fibronectin 1, insulin-like growth factor binding protein 3, and transforming growth factor beta-induced protein, were induced by hypoxia in SSc and healthy dermal fibroblasts. The induction of these genes was time- and dose-dependent. Experiments with HIF-1alpha-knockout mouse embryonic fibroblasts, deferoxamine/cobalt ions as chemical stabilizers of HIF-1alpha, and HIF-1alpha small interfering RNA consistently showed that extracellular matrix genes are induced in dermal fibroblasts by HIF-1alpha-dependent, as well as HIF-1alpha-independent, mechanisms. Using the systemic normobaric hypoxia mouse model, we demonstrated that dermal hypoxia leads to the induction of the identified extracellular matrix genes in vivo after both short exposure and prolonged exposure to hypoxia.

CONCLUSION

These data show that hypoxia contributes directly to the progression of fibrosis in patients with SSc by increasing the release of major extracellular matrix proteins. Targeting of hypoxia pathways might therefore be of therapeutic value in patients with SSc.

Tadalafil: Raynaud Phenomenon

Off-Label Drug Uses

This Hospital Pharmacy feature is extracted from Off-Label DrugFacts, a quarterly publication available from Wolters Kluwer Health. Off-Label DrugFacts is a practitioner-oriented resource for information about specific FDA-unapproved drug uses. This new guide to the literature will enable the health care professional/clinician to quickly identify published studies on off-label uses and to determine if a specific use is rational in a patient care scenario. The most relevant data are provided in tabular form, so the reader can easily identify the scope of information available. A summary of the data—including background, study design, patient population, dosage information, therapy duration, results, safety, and therapeutic considerations—precedes each table of published studies. References direct the reader to the full literature for more comprehensive information prior to patient care decisions. Direct questions or comments regarding “Off-Label Drug Uses” to hospitalpharmacy@drugfacts.com .

Iloprost treatment in patients with Raynaud's phenomenon secondary to systemic sclerosis and the quality of life: a new therapeutic protocol

OBJECTIVES

To evaluate the clinical efficacy and the effects on the quality of life of iloprost, a prostacyclin analogue, used according to a new protocol in patients with Raynaud's phenomenon secondary to systemic sclerosis.

METHODS

In this randomized study, we treated 30 patients with iloprost, given by intravenous infusion, at progressively increasing doses (from 0.5 to 2 ng/kg/min) over a period of 6 h each day for 10 days in two consecutive weeks, with repeated cycles at regular intervals of 3 months for 18 months. The results were compared with those obtained in 30 other patients who received the same drug but with different dosing schemes.

RESULTS

The total average daily duration of the attacks, the average duration of a single attack and the average daily frequency of the attacks were reduced significantly in all treatment groups, but the comparison between the groups demonstrated significant differences between patients treated with the new protocol and the others at later times (12 and 18 months). The effects on the quality of life in the group treated with the new protocol, evaluated with the Short Form-36, demonstrated a marked improvement regarding both the scale relating to the physical aspect of the illness and, especially, the scale relating to the mental aspect.

CONCLUSIONS

In patients with systemic sclerosis, cyclic intravenous iloprost infusion is efficacious in the treatment of Raynaud's phenomenon. The protocol that we used, compared with others, not only has favourable clinical effects but also leads to a marked improvement in the quality of life.

Sildenafil: Raynaud Phenomenon

Off-Label Drug Uses

This Hospital Pharmacy feature is extracted from Off-Label DrugFacts, a quarterly publication available from Wolters Kluwer Health. Off-Label DrugFacts is a practitioner-oriented resource for information about specific FDA-unapproved drug uses. This new guide to the literature will enable the health care professional/clinician to quickly identify published studies on off-label uses and to determine if a specific use is rational in a patient care scenario. The most relevant data are provided in tabular form, so the reader can easily identify the scope of information available. A summary of the data—including background, study design, patient population, dosage information, therapy duration, results, safety, and therapeutic considerations—precedes each table of published studies. References direct the reader to the full literature for more comprehensive information prior to patient care decisions. Direct questions or comments regarding “Off-Label Drug Uses” to hospital pharmacy@drugfacts.com .

Endothelin-1 response to mental stress in early ischemic lesions of the extremities due to systemic sclerosis

We studied circulating levels of endothelin-1, catecholamines and nitric oxide after a mental arithmetic test in 14 patients with early ischemic lesions of the extremities due to systemic sclerosis and slightly impaired peripheral vascular flow. The test induced an increase (P<0.01) in blood pressure, heart rate, endothelin-1 and catecholamine levels, whereas it did not change the low basal levels of nitric oxide. In healthy subjects (n=20) the test significantly (P<0.01) decreased endothelin-1 without affecting nitric oxide. The low basal levels of nitric oxide and the high plasma concentration of endothelin-1 after psychological stress cannot be explained by an impaired release from the limited ischemic lesions alone. This suggests a diffuse microvascular derangement that aggravates the course of peripheral microvascular ischemic lesions.

Endothelial dysfunction and activation as an expression of disease: role of prostacyclin analogs

The endothelium is now considered a real endocrine-paracrine organ, important not only as a structural barrier between the circulation and surrounding tissue, but also because it plays an essential role for local hemodynamics, releasing substances that modulate the vascular calibre and blood cell activation. Here, after a brief but detailed analysis of the importance of the endothelium in vascular homeostasis, in the control of coagulation and in the relations with the different blood cells, we will explain the concept of endothelial dysfunction (altered NO release) and activation (amplified adhesion molecule expression) in inflammatory, connective tissue and post-trasplantation diseases. Furthermore, this review will focus on the activity of prostacyclin and synthetic analogs, especially their ability to interact with the vasodilatation system and their role in modulating cell interaction by surface adhesion molecule expression, cytokines and growth factors release as well as gene transcription factors. Finally, we will consider the therapeutic role of prostacyclin analogs in the prevention and treatment of connective tissue diseases.

Fluoxetine: Raynaud's Phenomenon

Off-Label Drug Uses

This Hospital Pharmacy feature is extracted from Off-Label DrugFacts, a quarterly publication available from Facts and Comparisons. Off-Label DrugFacts is a practitioner-oriented resource for information about specific FDA-unapproved drug uses. This new guide to the literature will enable the health care professional/clinician to quickly identify published studies on off-label uses and to determine if a specific use is rational in a patient care scenario. The most relevant data are provided in tabular form so that the reader can easily identify the scope of information available. A summary of the data–including, background, study design, patient population, dosage information, therapy duration, results, safety, and therapeutic considerations–precedes each table of published studies. References direct the reader to the full literature for more comprehensive information prior to patient care decisions. Direct questions or comments on “Off-Label Drug Uses” to hospitalpharmacy@drugfacts.com .

Raynaud's phenomenon

Raynaud's phenomenon is characterised by episodic vasospasm of the fingers and toes typically precipitated by exposure to cold. Mild Raynaud's is common and is not usually a harbinger of clinically important disability; its onset, however, can be startling and uncomfortable for patients, and the well recognised association in some cases with systemic rheumatic conditions often precipitates aggressive assessments for underlying diseases. Advances in vascular physiology have shed light on the role of the endothelium as well as endothelium-independent mechanisms in the altered vasoregulation of Raynaud's. We review clinical aspects of the disorder and new insights with respect to pathophysiology, and we discuss potential new therapeutics based on the disease mechanism, such as prostacyclin analogues, serotonin antagonists, and calcitonin gene-related peptides.

Vascular function in systemic sclerosis

Raynaud phenomenon is often the earliest manifestation of systemic sclerosis. This fact highlights the role of vascular dysfunction early on in the disease process. Although this review deals primarily with digital vasculature, recent research confirms that vascular dysfunction is widespread, and affects large as well as small vessels. Abnormalities of vascular function and structure are interdependent, and together result in the ischemic atrophy so characteristic of SSc. Key areas of research include the pathophysiology of the imbalance between vasodilation and vasoconstriction, with particular interest in understanding the relative contributions of endothelial-dependent and endothelial-independent vasodilation, and the development of new methodologies by which to quantify vascular function.