Ultrastructural changes of vascular smooth muscle cells and resistance to vasospasm treatment in femoral arteries of an arteriosclerotic rat model.

The objective of this study was to establish an animal model of arteriosclerosis for assessing vasospasm and to investigate the relationship between arteriosclerosis and vasospasm. Twelve-week-old male Sprague-Dawley rats were fed a diet supplemented with adenine and vitamin D (adenine/vitD). Body weight, blood, and femoral artery histopathology were assessed at 2, 4, and 6 weeks. Change in the femoral artery was examined by transmission electron microscope (TEM). Vasospasm was induced by administering epinephrine extravascularly into the femoral artery and released by the treatment with lidocaine as a vasodilator. During this period, the extravascular diameter and blood flow were measured. The rats in the adenine/vitD group developed renal dysfunction, uremia, hyperphosphatemia, and elevated serum alkaline phosphatase. Histological and TEM analyses of the femoral arteries in the treated rats revealed the degeneration of elastic fibers and extensive calcification of the tunica media and intima. Vascular smooth muscles were degenerated and osteoblasts were developed, resulting in calcified arteriosclerosis. Vasospasm in arteriosclerotic arteries was detected; however, vasodilation as well as an increase in the blood flow was not observed. This study revealed the development of vasospasm in the femoral arteries of the arteriosclerotic rats and, a conventional vasodilator did not release the vasospasm.

Microbe-Derived Butyrate and Its Receptor, Free Fatty Acid Receptor 3, But Not Free Fatty Acid Receptor 2, Mitigate Neointimal Hyperplasia Susceptibility After Arterial Injury.

Background Arterial restenosis after vascular surgery is a common cause of midterm restenosis and treatment failure. Herein, we aim to investigate the role of microbe-derived butyrate, FFAR2 (free fatty acid receptor 2), and FFAR3 (free fatty acid receptor 3) in mitigating neointimal hyperplasia development in remodeling murine arteries after injury. Methods and Results C57BL/6 mice treated with oral vancomycin before unilateral femoral wire injury to deplete gut microbiota had significantly diminished serum and stool butyrate and more neointimal hyperplasia development after arterial injury, which was reversed by concomitant butyrate supplementation. Deficiency of FFAR3 but not FFAR2, both receptors for butyrate, exacerbated neointimal hyperplasia development after injury. FFAR3 deficiency was also associated with delayed recovery of the endothelial layer in vivo. FFAR3 gene expression was observed in multiple peripheral arteries, and expression was increased after arterial injury. Treatment of endothelial but not vascular smooth muscle cells with the pharmacologic FFAR3 agonist 1-methylcyclopropane carboxylate stimulated cellular migration and proliferation in scratch assays. Conclusions Our results support a protective role for butyrate and FFAR3 in the development of neointimal hyperplasia after arterial injury and delineate activation of the butyrate-FFAR3 pathway as a valuable strategy for the prevention and treatment of neointimal hyperplasia.

Non-Invasive Management of Peripheral Arterial Disease.

BACKGROUND: Peripheral arterial disease (PAD) is common and symptoms can be debilitating and lethal. Risk management, exercise, radiological and surgical intervention are all valuable therapies, but morbidity and mortality rates from this disease are increasing. Circulatory enhancement can be achieved using simple medical electronic devices, with claims of minimal adverse side effects. The evidence for these is variable, prompting a review of the available literature. METHODS: Embase and Medline were interrogated for full text articles in humans and written in English. Any external medical devices used in the management of peripheral arterial disease were included if they had objective outcome data. RESULTS: Thirty-one papers met inclusion criteria, but protocols were heterogenous. The medical devices reported were intermittent pneumatic compression (IPC), electronic nerve (NMES) or muscle stimulators (EMS), and galvanic electrical dressings. In patients with intermittent claudication, IPC devices increase popliteal artery velocity (49-70 %) and flow (49-84 %). Gastrocnemius EMS increased superficial femoral artery flow by 140 %. Over 4.5-6 months IPC increased intermittent claudication distance (ICD) (97-150 %) and absolute walking distance (AWD) (84-112 %), with an associated increase in quality of life. NMES of the calf increased ICD and AWD by 82 % and 61-150 % at 4 weeks, and 26 % and 34 % at 8 weeks. In patients with critical limb ischaemia IPC reduced rest pain in 40-100 % and was associated with ulcer healing rates of 26 %. IPC had an early limb salvage rate of 58-83 % at 1-3 months, and 58-94 % at 1.5-3.5 years. No studies have reported the use of EMS or NMES in the management of CLI. CONCLUSION: There is evidence to support the use of IPC in the management of claudication and CLI. There is a building body of literature to support the use of electrical stimulators in PAD, but this is low level to date. Devices may be of special benefit to those with limited exercise capacity, and in non-reconstructable critical limb ischaemia. Galvanic stimulation is not recommended.

Investigation of the Effects and Mechanisms of Mai Tong Formula on Lower Limb Macroangiopathy in a Spontaneous Diabetic Rat Model.

A new Chinese herbal formula called Mai Tong Formulae (MTF) has recently been used to treat lower limb macroangiopathy in type 2 diabetes mellitus (T2DM) patients. In this study, we investigated the effect of MTF on lower limb macroangiopathy in a spontaneous diabetic rat model (GK rats). We found that MTF treatment significantly reduced serum fasting blood glucose (FBG), triglycerides (TG), total cholesterol (TC), IL6, and VEGF and increased serum insulin in this model. Histological and ultrastructural observations showed that MTF treatment significantly reduced vascular endothelial cell shedding and improved endothelium injuries. We further detect proteome alteration following MTF treatment. 25 differential proteins (DPs) abnormally expressed in GK rats were normalized by MTF treatment. These DPs significantly are enriched in biological processes and pathways that regulate muscle contraction and cGMP-PKG signaling pathway and so on. Additional protein-protein interaction (PPI) network analyses of the DPs showed that Fasn and Prkar2a are involved in the AMPK signaling pathway, and Gnas, Myh11, and Myh6 are involved in vascular smooth muscle contraction; these 5 DPs were validated by Western blotting. These results indicate that MTF treatment effectively treats lower limb macroangiopathy by regulating key proteins involved in AMPK signaling pathway and vascular smooth muscle contraction.

Access Options for Transcatheter Aortic Valve Replacement in Patients with Unfavorable Aortoiliofemoral Anatomy.

In the current era, 10-15 % of transcatheter aortic valve replacement (TAVR)-eligible high and prohibitive risk patients with severe symptomatic aortic stenosis are not candidates for transfemoral arterial access. Knowledge of the various alternative access options can enable TAVR teams to provide improved quality of life and potentially life-saving treatment for a group of patients who otherwise have no viable options. In this article, we review approach to patients with unfavorable femoral arterial anatomy and provide an in-depth discussion on the various alternative routes for TAVR.

The Effect of Ozone Therapy on Experimental Vasospasm in the Rat Femoral Artery.

AIM: Oxidation products following subarachnoid hemorrhage (SAH) are among the causative substances of cerebral vasospasm and poor outcome. Ozone (O3) is a gas that contains three atoms of oxygen with a cyclic structure. It has been suggested that application of low-dose ozone has an antioxidant effect and provides resistance to oxidative stress. We investigated the effect of oxygen-ozone therapy on rat femoral artery vasospasm. MATERIAL AND METHODS: Twenty-four male Sprague-Dawley rats were randomly separated into vasospasm, vasospasm + ozone and control groups. The femoral artery vasospasm model was used. Rats in the vasospasm + ozone group were given 4 mL of ozone (20 µ/mL) daily for 7 days. Femoral arteries were examined by light microscopy for histological changes and morphometric analysis. Kruskal Wallis test and Mann Whitney U tests were used for the statistical analysis. The values of p < 0.01 and p < 0.05 were recognized as statistically significant. RESULTS: Ozone treatment reduced the morphometric changes as irregularity of the elastic lamina, disruption of the endothelial cells, vacuolization and hemorrhages that caused by vasospasm. The measurements of the wall thickness (p=0.003; p < 0.01) and lumen diameter (p=0.001; p < 0.01) showed statistically significant difference (p < 0.01) between the vasospasm and vasospasm+ozone groups. CONCLUSION: Ozone therapy may be useful in the treatment of post-hemorrhagic vasospasm.

Long-term Treatment with Hesperidin Improves Endothelium-dependent Vasodilation in Femoral Artery of Spontaneously Hypertensive Rats: The Involvement of NO-synthase and Kv Channels.

Hesperidin is the most common flavonoid found in citrus fruits and is expected to exert vasodilation action relevant to its health benefits. The present study aimed to explore the effect of hesperidin on the vascular responses in normotensive and hypertensive rats and the involvement of NO-synthase and Kv channels. The 15-week-old Wistar and spontaneously hypertensive rats (SHR) were randomized to orally receive either hesperidin (50 mg/kg/day) or a corresponding volume of the water for 4 weeks. Vascular responses of isolated femoral arteries were studied with myograph in control conditions and during inhibition of NO-synthase with l-NNA and Kv channels with 4-AP. Hesperidin had no effect on blood pressure. Endothelium-dependent vasodilation in Wistar and SHR was significantly improved by the treatment with hesperidin. The contraction responses after l-NNA were increased in all groups of rats to similar extent, but relaxatory responses were significantly attenuated only in SHR. The inhibition of Kv channels significantly reduced endothelium-dependent vasodilatory responses in only in SHR administered with hesperidin. The results of our experiment indicate that hesperidin might improve the endothelium-dependent vasodilation during hypertension, possibly through the enhancement of Kv channels function. Copyright © 2016 John Wiley & Sons, Ltd.

Evaluation of Hemostatic Effects of Carbonized Hair-Loaded Poly(L-Lactic) Acid Nanofabrics.

Carbonized human hair is used to stop bleeding in traditional Chinese medicine. The present study was aimed to prepare a novel nanofiber containing carbonized human hair and evaluate its hemostatic effect. Carbonized human hair-loaded poly(L-lactic) acid nanofiber was prepared by electrospinning. The hemostatic efficacies of dressings composed of either carbonized human hair, carbonized human hair-loaded poly(L-lactic) acid nanofiber, Yunnan White Drug power or poly(L-lactic) acid nanofiber were investigated in several swine arterial and venous bleeding models. Blood loss and bleeding time were measured. In vitro, carbonized human hair, carbonized human hair-loaded nanofiber and Yunnan White Drug Powder significantly shortened the clotting time in comparison with the nanofiber control group. The hemostatic effects of the carbonized human hair-load nanofiber on liver and spleen traumatic wounds were better than those of carbonized human hair and Yunnan White Drug Powder in terms of blood loss and bleeding time. Similar effects were observed in swine femoral artery wound model. In the swine femoral vein wound model, bleeding could not be stopped in the control animals. In the carbonized human hair group, Yunnan White Drug Powder group and carbonized human hair-load nanofiber group, bleeding was stopped in 83.3%, 83.3% and 100% of the animals, respectively. In conclusion, dressing using carbonized human hair-load nanofibers is effective in controlling severe, uncontrolled bleeding. This dressing may offer a cheap alternative to dressings composed of coagulation proteins.

Nitric Oxide Increases Arterial Endotheial Permeability through Mediating VE-Cadherin Expression during Arteriogenesis.

Macrophage invasion is an important event during arteriogenesis, but the underlying mechanism is still only partially understood. The present study tested the hypothesis that nitric oxide (NO) and VE-cadherin, two key mediators for vascular permeability, contribute to this event in a rat ischemic hindlimb model. In addition, the effect of NO on expression of VE-caherin and endothelial permeability was also studied in cultured HUVECs. We found that: 1) in normal arteriolar vessels (NAV), eNOS was moderately expressed in endothelial cells (EC) and iNOS was rarely detected. In contrast, in collateral vessels (CVs) induced by simple femoral artery ligation, both eNOS and iNOS were significantly upregulated (P<0.05). Induced iNOS was found mainly in smooth muscle cells, but also in other vascular cells and macrophages; 2) in NAV VE-cadherin was strongly expressed in EC. In CVs, VE-cadherin was significantly downregulated, with a discontinuous and punctate pattern. Administration of nitric oxide donor DETA NONOate (NONOate) further reduced the amounts of Ve-cadherin in CVs, whereas NO synthase inhibitor L-NAME inhibited downregulation of VE-cadherin in CVs; 3) in normal rats Evans blue extravasation (EBE) was low in the musculus gracilis, FITC-dextron leakage was not detected in the vascular wall and few macrophages were observed in perivascular space. In contrast, EBE was significantly increased in femoral artery ligation rats, FITC-dextron leakage and increased amounts of macrophages were detected in CVs, which were further enhanced by administration of NONOate, but inhibited by L-NAME supplement; 4) in vitro experiments confirmed that an increase in NO production reduced VE-cadherin expression, correlated with increases in the permeability of HUVECs. In conclusion, our data for the first time reveal the expression profile of VE-cadherin and alterations of vascular permeability in CVs, suggesting that NO-mediated VE-cadherin pathway may be one important mechanism responsible, at least in part, for macrophage invasion during arteriogenesis.

Endogenously generated omega-3 fatty acids attenuate vascular inflammation and neointimal hyperplasia by interaction with free fatty acid receptor 4 in mice.

BACKGROUND: Omega-3 polyunsaturated fatty acids (ω3 PUFAs) suppress inflammation through activation of free fatty acid receptor 4 (FFAR4), but this pathway has not been explored in the context of cardiovascular disease. We aimed to elucidate the involvement of FFAR4 activation by ω3 PUFAs in the process of vascular inflammation and neointimal hyperplasia in mice. METHODS AND RESULTS: We used mice with disruption of FFAR4 (Ffar4(-/-)), along with a strain that synthesizes high levels of ω3 PUFAs (fat-1) and a group of crossed mice (Ffar4(-/-)/fat-1), to elucidate the role of FFAR4 in vascular dysfunction using acute and chronic thrombosis/vascular remodeling models. The presence of FFAR4 in vascular-associated cells including perivascular adipocytes and macrophages, but not platelets, was demonstrated. ω3 PUFAs endogenously generated in fat-1 mice (n=9), but not in compound Ffar4(-/-)/fat-1 mice (n=9), attenuated femoral arterial thrombosis induced by FeCl3. Neointimal hyperplasia and vascular inflammation in the common carotid artery were significantly curtailed 4 weeks after FeCl3 injury in fat-1 mice (n=6). This included greater luminal diameter and enhanced blood flow, reduced intima:media ratio, and diminished macrophage infiltration in the vasculature and perivascular adipose tissue compared with control mice. These effects were attenuated in the Ffar4(-/-)/fat-1 mice. CONCLUSIONS: These results indicate that ω3 PUFAs mitigate vascular inflammation, arterial thrombus formation, and neointimal hyperplasia by interaction with FFAR4 in mice. Moreover, the ω3 PUFA-FFAR4 pathway decreases inflammatory responses with dampened macrophage transmigration and infiltration.

Investigation of possible prophylactic, renoprotective, and cardioprotective effects of thromboprophylactic drugs against ischemia-reperfusion injury.

The aim of this study was to investigate whether anticoagulant and antiaggregant agents have protective effects against oxidative damage induced by peripheral ischemia-reperfusion (I/R). Groups were created as follows: control group, I/R group (sham group), I/R plus acetylsalicylic acid (Group I), I/R+clopidogrel (Group II), I/R+rivaroxaban (Group III), I/R+bemiparin sodium (Group IV), and I/R+enoxaparin sodium (Group V). In Groups I, II, III, IV, and V, drugs were administered daily for 1 week before I/R creation. Peripheral I/R was induced in the I/R groups by clamping the right femoral artery. The rats were sacrificed 1 hour after reperfusion. Nitrogen oxide levels, malondialdehyde (MDA) levels, paraoxonase-1 (PON1) activity, and prolidase activity were evaluated in both cardiac and renal tissues. There was no significant difference in nitrogen oxide levels between the groups. However, cardiac and renal MDA were significantly higher and PON1 activity was markedly lower in the I/R groups compared with the control group (p<0.05). Although elevated prolidase activity was detected in both the cardiac and renal tissue of the I/R groups, only the sham group and Group V had significantly higher renal prolidase activity (p<0.05). Group V had significantly higher cardiac MDA, PON1, prolidase levels, and renal prolidase activity compared with the sham group (p<0.05). Significant improvement in renal MDA levels was only observed in Group III, and marked improvement was observed in the cardiac MDA levels of Group II when compared with the sham group (p<0.05). Thromboprophylactic agents appear to provide partial or prominent protection against I/R injury.

Menaquinone-7 supplementation improves arterial stiffness in healthy postmenopausal women. A double-blind randomised clinical trial.

Observational data suggest a link between menaquinone (MK, vitamin K2) intake and cardiovascular (CV) health. However, MK intervention trials with vascular endpoints are lacking. We investigated long-term effects of MK-7 (180 µg MenaQ7/day) supplementation on arterial stiffness in a double-blind, placebo-controlled trial. Healthy postmenopausal women (n=244) received either placebo (n=124) or MK-7 (n=120) for three years. Indices of local carotid stiffness (intima-media thickness IMT, Diameter end-diastole and Distension) were measured by echotracking. Regional aortic stiffness (carotid-femoral and carotid-radial Pulse Wave Velocity, cfPWV and crPWV, respectively) was measured using mechanotransducers. Circulating desphospho-uncarboxylated matrix Gla-protein (dp-ucMGP) as well as acute phase markers Interleukin-6 (IL-6), high-sensitive C-reactive protein (hsCRP), tumour necrosis factor-α (TNF-α) and markers for endothelial dysfunction Vascular Cell Adhesion Molecule (VCAM), E-selectin, and Advanced Glycation Endproducts (AGEs) were measured. At baseline dp-ucMGP was associated with IMT, Diameter, cfPWV and with the mean z-scores of acute phase markers (APMscore) and of markers for endothelial dysfunction (EDFscore). After three year MK-7 supplementation cfPWV and the Stiffness Index ßsignificantly decreased in the total group, whereas distension, compliance, distensibility, Young's Modulus, and the local carotid PWV (cPWV) improved in women having a baseline Stiffness Index ß above the median of 10.8. MK-7 decreased dp-ucMGP by 50 % compared to placebo, but did not influence the markers for acute phase and endothelial dysfunction. In conclusion, long-term use of MK-7 supplements improves arterial stiffness in healthy postmenopausal women, especially in women having a high arterial stiffness.

Effects of light-emitting diode (LED) therapy on skeletal muscle ischemia reperfusion in rats.

Low-level laser therapy has been shown to decrease ischemia-reperfusion injuries in the skeletal muscle by induction of synthesis of antioxidants and other cytoprotective proteins. Recently, the light-emitting diode (LED) has been used instead of laser for the treatment of various diseases because of its low operational cost compared to the use of a laser. The objective of this work was to analyze the effects of LED therapy at 904 nm on skeletal muscle ischemia-reperfusion injury in rats. Thirty healthy male Wistar rats were allocated into three groups of ten rats each as follows: normal (N), ischemia-reperfusion (IR), and ischemia-reperfusion + LED (IR + LED) therapy. Ischemia was induced by right femoral artery clipping for 2 h followed by 2 h of reperfusion. The IR + LED group received LED irradiation on the right gastrocnemius muscle (4 J/cm(2)) immediately and 1 h following blood supply occlusion for 10 min. At the end of trial, the animals were euthanized and the right gastrocnemius muscles were submitted to histological and histochemical analysis. The extent of muscle damage in the IR + LED group was significantly lower than that in the IR group (P < 0.05). In comparison with other groups, tissue malondialdehyde (MDA) levels in the IR group were significantly increased (P < 0.05). The muscle tissue glutathione (GSH), superoxide dismutases (SOD), and catalase (CAT) levels in the IR group were significantly lower than those in the subjects in other groups. From the histological and histochemical perspective, the LED therapy has alleviated the metabolic injuries in the skeletal muscle ischemia reperfusion in this experimental model.

Aspirin enhances protective effect of fish oil against thrombosis and injury-induced vascular remodelling.

BACKGROUND AND PURPOSE: Although aspirin (acetylsalicylic acid) is commonly used to prevent ischaemic events in patients with coronary artery disease, many patients fail to respond to aspirin treatment. Dietary fish oil (FO), containing ω3 polyunsaturated fatty acids (PUFAs), has anti-inflammatory and cardio-protective properties, such as lowering cholesterol and modulating platelet activity. The objective of the present study was to investigate the potential additional effects of aspirin and FO on platelet activity and vascular response to injury. EXPERIMENTAL APPROACH: Femoral arterial remodelling was induced by wire injury in mice. Platelet aggregation, and photochemical- and ferric chloride-induced carotid artery thrombosis were employed to evaluate platelet function. KEY RESULTS: FO treatment increased membrane ω3 PUFA incorporation, lowered plasma triglyceride and cholesterol levels, and reduced systolic BP in mice. FO or aspirin alone inhibited platelet aggregation; however, when combined, they exhibited synergistic suppression of platelet activity in mice, independent of COX-1 inhibition. FO alone, but not aspirin, attenuated arterial neointimal growth in response to injury. Strikingly, a combination of FO and aspirin synergistically inhibited injury-induced neointimal hyperplasia and reduced perivascular inflammatory reactions. Moreover, co-administration of FO and aspirin decreased the expression of pro-inflammatory cytokines and adhesion molecules in inflammatory cells. Consistently, a pro-resolution lipid mediator-Resolvin E1, was significantly elevated in plasma in FO/aspirin-treated mice. CONCLUSIONS AND IMPLICATIONS: Co-administration of FO and low-dose aspirin may act synergistically to protect against thrombosis and injury-induced vascular remodelling in mice. Our results support further investigation of adjuvant FO supplementation for patients with stable coronary artery disease.

Clinical outcomes and safety of transfemoral aortic valve implantation under general versus local anesthesia: subanalysis of the French Aortic National CoreValve and Edwards 2 registry.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) performed under local anesthesia (LA) is becoming increasingly common. We aimed to compare the clinical outcomes in patients who underwent transfemoral-TAVI under general anesthesia (GA) and LA. METHODS AND RESULTS: Data from 2326 patients in the French Aortic National CoreValve and Edwards 2 (FRANCE 2) registry who underwent transfemoral-TAVI were analyzed. During the study period, the percentage of LA procedures increased gradually from 14% in January 2010 to 59% in October 2011. The clinical outcomes for GA (n=1377) and LA (n=949) were compared. Numerous baseline characteristics differed between the 2 groups, and the use of transesophageal echocardiographic guidance was more common in GA than in LA (76.3% versus 16.9%; P<0.001). Device success and cumulative 30-day survival rates were similar in the 2 groups (97.6% versus 97.0%; P=0.41 and 91.6% versus 91.3%; P=0.69, respectively), whereas the incidence of postprocedural aortic regurgitation≥mild was significantly lower in GA than in LA (15.0% versus 19.1%; P=0.015). The groups were also analyzed using a propensity-matching model, including transesophageal echocardiographic usage (GA [n=401] versus LA [n=401]). This model indicated that there were no significant differences between the 2 groups in the rates of 30-day survival (GA [91.4%] versus LA [89.3%]; P=0.27] and postprocedural aortic regurgitation≥mild (GA [12.7%] versus LA [16.2%]; P=0.19). CONCLUSIONS: The less invasive transfemoral-TAVI under LA is preferred in clinical settings and seems to be acceptable; however, the higher incidence of postprocedural aortic regurgitation is emphasized. Therapeutic efforts should be made to reduce such complications during transfemoral-TAVI under LA.

Supplementation of omega-3 polyunsaturated fatty acids prevents increase in arterial stiffness after experimental menopause.

BACKGROUND: Menopause is associated with increased arterial stiffness, an independent marker of cardiovascular risk. Omega-3 polyunsaturated fatty acids (N3-PUFAs) are thought to have multiple cardiovascular benefits, including prevention of arterial stiffness. We investigated whether treatment with N3-PUFA prevents increase in arterial stiffness in ovariectomized rats, an animal model of experimental menopause. METHODS: A total of 43 Wistar rats, 2 months old, were divided into 3 groups, control, sham surgery, normal diet (CTRL, n = 15); ovariectomy, normal diet (OVX, n = 14); and ovariectomy with N3-PUFA supplementation (0.8 g/kg/d in daily gavages administration; OVX + O3, n = 14). Two months after surgery, carotid-femoral pulse wave velocity (PWV) and arterial blood pressure (BP) were measured by carotid and femoral cannulation. Aortic morphometric measurements were performed after dissection. RESULTS: Ovariectomy caused a significant increase in BP (P < .05), PWV (P < .0001), and elastic modulus (P = .001) compared to CTRL. After ovariectomy, N3-PUFA supplementation completely prevented increase in arterial stiffness (P < .0001 vs OVX) and BP (P < .05 vs OVX) and resulted in a significant increase in body weight and aortic thickness. CONCLUSIONS: In an experimental model of menopause, N3-PUFA supplementation prevents arterial stiffening and other vascular changes induced by ovariectomy. These results represent a therapeutic benefit of N3-PUFAs in prevention of postmenopausal cardiovascular disease.

Far red/near infrared light treatment promotes femoral artery collateralization in the ischemic hindlimb.

Nitric oxide (NO) is a crucial mediator of hindlimb collateralization and angiogenesis. Within tissues there are nitrosyl-heme proteins which have the potential to generate NO under conditions of hypoxia or low pH. Low level irradiation of blood and muscle with light in the far red/near infrared spectrum (670 nm, R/NIR) facilitates NO release. Therefore, we assessed the impact of red light exposure on the stimulation of femoral artery collateralization. Rabbits and mice underwent unilateral resection of the femoral artery and chronic R/NIR treatment. The direct NO scavenger carboxy-PTIO and the nitric oxide synthase (NOS) inhibitor L-NAME were also administered in the presence of R/NIR. DAF fluorescence assessed R/NIR changes in NO levels within endothelial cells. In vitro measures of R/NIR induced angiogenesis were assessed by endothelial cell proliferation and migration. R/NIR significantly increased collateral vessel number which could not be attenuated with L-NAME. R/NIR induced collateralization was abolished with c-PTIO. In vitro, NO production increased in endothelial cells with R/NIR exposure, and this finding was independent of NOS inhibition. Similarly R/NIR induced proliferation and tube formation in a NO dependent manner. Finally, nitrite supplementation accelerated R/NIR collateralization in wild type C57Bl/6 mice. In an eNOS deficient transgenic mouse model, R/NIR restores collateral development. In conclusion, R/NIR increases NO levels independent of NOS activity, and leads to the observed enhancement of hindlimb collateralization.

Dose dependent morphological effects of alpha lipoic acid on vasospastic femoral artery in rats.

AIM: The dose dependent effects of alpha lipoic acid (α-LA) were investigated morphologically on rat vasospasm model. MATERIAL AND METHODS: 32 rats were divided into four groups: group I=control; group II=vasospasm; group III=vasospasm +low dose (20 mg/kg) intraperitoneal α-LA administered; and group IV=vasospasm +high dose (100 mg/kg) intraperitoneal α-LA administered. Histological and morphometric examinations were carried out for each groups under light microscope. RESULTS: The mean vascular wall thickness displayed significant increase in group II and III compared with group I (p < .05). Statistical comparison of group II and IV, regarding vascular wall thickness showed a significant decrease in group IV, and regarding vascular lumen area showed a significant increase in group IV (p < .05). CONCLUSION: It is demonstrated α-LA reduces the effects of vasospasm in high dose treatment group by decreasing the wall thickness and increasing the lumen surface area. The present study suggests that adequate dose of α-LA is a potential therapeutic agent in experimental vasospasm model.