Absence of inflammatory conditions in human varicose saphenous veins

Utility of routine laboratory tests in the assessment of chronic venous disease progression in female patients

Chronic venous disease (CVD) is a frequently encountered disease that progresses with age. Although the principal method of evaluation and diagnosis is Doppler ultrasound, routine laboratory tests may be an easier and more accessible way to evaluate CVD progression. The present retrospective study evaluated the laboratory results of 256 patients diagnosed with CVD. According to the Clinical, Etiological, Anatomical and Pathophysiological classification, depending on the CVD stage, patients were stratified into three groups: Group 1 (C2-C3; mild disease), Group 2 (C4; moderate to severe disease) and Group 3 (C5-C6; severe disease). The considered parameters were age, red blood cell count (RBC), white blood cell count (WBC) and platelet count (PLT), percentage of neutrophils and lymphocytes, neutrophil-to-lymphocyte ratio (NLR), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), fibrinogen, prothrombin time (in percentages and seconds), internal normalized ratio, activated partial thromboplastin time, creatine kinase (CK), CK myocardial band, alanine transaminase, aspartate transaminase, total bilirubin and urea. No significant differences among the groups were noted in RBC, WBC, PLT and coagulation factors; on the other hand, inflammatory markers exhibited differences among the groups. Several differences were observed in hepatic, metabolic and muscle tissue markers. Intraluminal thrombus formation in the case of varicose veins (thrombophlebitis) may be due to conditions of turbulent flow, stasis and endothelial inflammation, rather than hypercoagulability. The results of the present study confirmed the implication of inflammatory factors in pathophysiological modifications, including thickening of venous walls and valvular modification, as well as the appearance of intraluminal thrombi and trophic lesions. NLR, ESR, CRP and fibrinogen were increased with CVD progression and may be considered useful markers in evaluating CVD progression. Simple blood tests may provide phlebologists with additional insight for the management of those patients.

Reverse Regulatory Pathway (H2S / PGE2 / MMP) in Human Aortic Aneurysm and Saphenous Vein Varicosity

Hydrogen sulfide (H₂S) is a mediator with demonstrated protective effects for the cardiovascular system. On the other hand, prostaglandin (PG)E₂ is involved in vascular wall remodeling by regulating matrix metalloproteinase (MMP) activities. We tested the hypothesis that endogenous H₂S may modulate PGE₂, MMP-1 activity and endogenous tissue inhibitors of MMPs (TIMP-1/-2). This regulatory pathway could be involved in thinning of abdominal aortic aneurysm (AAA) and thickening of saphenous vein (SV) varicosities. The expression of the enzyme responsible for H₂S synthesis, cystathionine-γ-lyase (CSE) and its activity, were significantly higher in varicose vein as compared to SV. On the contrary, the endogenous H₂S level and CSE expression were lower in AAA as compared to healthy aorta (HA). Endogenous H₂S was responsible for inhibition of PGE₂ synthesis mostly in varicose veins and HA. A similar effect was observed with exogenous H₂S and consequently decreasing active MMP-1/TIMP ratios in SV and varicose veins. In contrast, in AAA, higher levels of PGE₂ and active MMP-1/TIMP ratios were found versus HA. These findings suggest that differences in H₂S content in AAA and varicose veins modulate endogenous PGE₂ production and consequently the MMP/TIMP ratio. This mechanism may be crucial in vascular wall remodeling observed in different vascular pathologies (aneurysm, varicosities, atherosclerosis and pulmonary hypertension).

Decreased PGE₂ content reduces MMP-1 activity and consequently increases collagen density in human varicose vein

Varicose veins are elongated and dilated saphenous veins. Despite the high prevalence of this disease, its pathogenesis remains unclear.

AIMS

In this study, we investigated the control of matrix metalloproteinases (MMPs) expression by prostaglandin (PG)E₂ during the vascular wall remodeling of human varicose veins.

METHODS AND RESULTS

Varicose (small (SDv) and large diameter (LDv)) and healthy saphenous veins (SV) were obtained after surgery. Microsomal and cytosolic PGE-synthases (mPGES and cPGES) protein and mRNA responsible for PGE₂ metabolism were analyzed in all veins. cPGES protein was absent while its mRNA was weakly expressed. mPGES-2 expression was similar in the different saphenous veins. mPGES-1 mRNA and protein were detected in healthy veins and a significant decrease was found in LDv. Additionally, 15-hydroxyprostaglandin dehydrogenase (15-PGDH), responsible for PGE₂ degradation, was over-expressed in varicose veins. These variations in mPGES-1 and 15-PGDH density account for the decreased PGE₂ level observed in varicose veins. Furthermore, a significant decrease in PGE₂ receptor (EP4) levels was also found in SDv and LDv. Active MMP-1 and total MMP-2 concentrations were significantly decreased in varicose veins while the tissue inhibitors of metalloproteinases (TIMP -1 and -2), were significantly increased, probably explaining the increased collagen content found in LDv. Finally, the MMP/TIMP ratio is restored by exogenous PGE₂ in varicose veins and reduced in presence of an EP4 receptor antagonist in healthy veins.

CONCLUSIONS

In conclusion, PGE₂ could be responsible for the vascular wall thickening in human varicose veins. This mechanism could be protective, strengthening the vascular wall in order to counteract venous stasis.