Effects of Gender and Vitamin D on Vascular Reactivity of the Carotid Artery on a Testosterone-Induced PCOS Model.

The negative cardiovascular effects of polycystic ovary syndrome (PCOS) and vitamin D deficiency (VDD) have been discussed previously; however, the sex differences between PCOS females and males are not yet known. Our aim was to investigate the effect of PCOS and VDD in the carotid artery of male and female Wistar rats. Females were treated with transdermal testosterone (Androgel) for 8 weeks, which caused PCOS. VDD and vitamin D supplementation were accomplished via diet. The carotid arteries' contraction and relaxation were examined using myography. Receptor density was investigated using immunohistochemistry. In PCOS females, angiotensin receptor density, angiotensin II-induced contraction, androgen receptor optical density, and testosterone-induced relaxation increased. The increased contractile response may increase cardiovascular vulnerability in women with PCOS. As an effect of VDD, estrogen receptor density increased in all our groups, which probably compensated for the reduced relaxation caused by VDD. Testosterone-induced relaxation was decreased as a result of VDD in males and non-PCOS females, whereas this reduction was absent in PCOS females. Male sex is associated with increased contraction ability compared with non-PCOS and PCOS females. VDD and Androgel treatment show significant gender differences in their effects on carotid artery reactivity. Both VDD and PCOS result in a dysfunctional vascular response, which can contribute to cardiovascular diseases.

Role of CB1 Cannabinoid Receptors in Vascular Responses and Vascular Remodeling of the Aorta in Female Mice.

Both the endocannabinoid system (ECS) and estrogens have significant roles in cardiovascular control processes. Cannabinoid type 1 receptors (CB1Rs) mediate acute vasodilator and hypotensive effects, although their role in cardiovascular pathological conditions is still controversial. Estrogens exert cardiovascular protection in females. We aimed to study the impact of ECS on vascular functions. Experiments were performed on CB1R knockout (CB1R KO) and wild-type (WT) female mice. Plasma estrogen metabolite levels were determined. Abdominal aortas were isolated for myography and histology. Vascular effects of phenylephrine (Phe), angiotensin II, acetylcholine (Ach) and estradiol (E2) were obtained and repeated with inhibitors of nitric oxide synthase (NOS, Nω-nitro-L-arginine) and of cyclooxygenase (COX, indomethacin). Histological stainings (hematoxylin-eosin, resorcin-fuchsin) and immunostainings for endothelial NOS (eNOS), COX-2, estrogen receptors (ER-α, ER-ß) were performed. Conjugated E2 levels were higher in CB1R KO compared to WT mice. Vasorelaxation responses to Ach and E2 were increased in CB1R KO mice, attenuated by NOS-inhibition. COX-inhibition decreased Phe-contractions, while it increased Ach-relaxation in the WT group but not in the CB1R KO. Effects of indomethacin on E2-relaxation in CB1R KO became opposite to that observed in WT. Histology revealed lower intima/media thickness and COX-2 density, higher eNOS and lower ER-ß density in CB1R KO than in WT mice. CB1R KO female mice are characterized by increased vasorelaxation associated with increased utilization of endothelial NO and a decreased impact of constrictor prostanoids. Our results indicate that the absence or inhibition of CB1Rs may have beneficial vascular effects.

Myoinositols Prevent Gestational Diabetes Mellitus and Related Complications: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Although gestational diabetes mellitus (GDM) has several short- and long-term adverse effects on the mother and the offspring, no medicine is generally prescribed to prevent GDM. The present systematic review and meta-analysis aimed to investigate the effect of inositol supplementation in preventing GDM and related outcomes. Systematic search was performed in CENTRAL, MEDLINE, and Embase until 13 September 2023. Eligible randomized controlled trials (RCTs) compared the efficacy of inositols to placebo in pregnant women at high risk for GDM. Our primary outcome was the incidence of GDM, whereas secondary outcomes were oral glucose tolerance test (OGTT) and maternal and fetal complications. (PROSPERO registration number: CRD42021284939). Eight eligible RCTs were identified, including the data of 1795 patients. The incidence of GDM was halved by inositols compared to placebo (RR = 0.42, CI: 0.26-0.67). Fasting, 1-h, and 2-h OGTT glucose levels were significantly decreased by inositols. The stereoisomer myoinositol also reduced the risk of insulin need (RR = 0.29, CI: 0.13-0.68), preeclampsia or gestational hypertension (RR = 0.38, CI: 0.2-0.71), preterm birth (RR = 0.44, CI: 0.22-0.88), and neonatal hypoglycemia (RR = 0.12, CI: 0.03-0.55). Myoinositol decrease the incidence of GDM in pregnancies high-risk for GDM. Moreover, myoinositol supplementation reduces the risk of insulin need, preeclampsia or gestational hypertension, preterm birth, and neonatal hypoglycemia. Based on the present study 2-4 g myoinositol canbe suggested from the first trimester to prevent GDM and related outcomes.

PARP2 downregulation in T cells ameliorates lipopolysaccharide-induced inflammation of the large intestine.

Introduction: T cell-dependent inflammatory response with the upregulation of helper 17 T cells (Th17) and the downregulation of regulatory T cells (Treg) accompanied by the increased production of tumor necrosis alpha (TNFa) is characteristic of inflammatory bowel diseases (IBD). Modulation of T cell response may alleviate the inflammation thus reduce intestinal damage. Poly(ADP-ribose) polymerase-2 (PARP2) plays role in the development, differentiation and reactivity of T cell subpopulations. Our aim was to investigate the potential beneficial effect of T cell-specific PARP2 downregulation in the lipopolysaccharide (LPS) induced inflammatory response of the cecum and the colon. Methods: Low-dose LPS was injected intraperitoneally to induce local inflammatory response, characterized by increased TNFa production, in control (CD4Cre; PARP2+/+) and T cell-specific conditional PARP2 knockout (CD4Cre; PARP2f/f) mice. TNFa, IL-1b, IL-17 levels were measured by ELISA, oxidative-nitrative stress was estimated by immunohistochemistry, while PARP1 activity, p38 MAPK and ERK phosphorylation, and NF-kB expression in large intestine tissue samples were examined by Western-blot. Systemic & local T cell subpopulation; Th17 and Treg alterations were also investigated using flowcytometry and immunohistochemistry. Results: In control animals, LPS induced intestinal inflammation with increased TNFa production, while no significant elevation of TNFa production was observed in T cell-specific PARP2 knockout animals. The absence of LPS-induced elevation in TNFa levels was accompanied by the absence of IL-1b elevation and the suppression of IL-17 production, showing markedly reduced inflammatory response. The increase in oxidative-nitrative stress and PARP1-activation was also absent in these tissues together with altered ERK and NF-kB activation. An increase in the number of the anti-inflammatory Treg cells in the intestinal mucosa was observed in these animals, together with the reduction of Treg count in the peripheral circulation. Discussion: Our results confirmed that T cell-specific PARP2 downregulation ameliorated LPS-induced colitis. The dampened TNFa production, decreased IL-17 production and the increased intestinal regulatory T cell number after LPS treatment may be also beneficial during inflammatory processes seen in IBD. By reducing oxidative-nitrative stress and PARP1 activation, T cell-specific PARP2 downregulation may also alleviate intestinal tissue damage.

Delta 9-tetrahydrocannabinol conserves cardiovascular functions in a rat model of endotoxemia: Involvement of endothelial molecular mechanisms and oxidative-nitrative stress.

In endotoxemic models, the inflammatory parameters are altered to a favorable direction as a response to activation of cannabinoid receptors 1 and 2. The phytocannabinoid Δ9-tetrahydrocannabinol (THC) is an agonist/partial antagonist of both cannabinoid receptors. This report targets the effects of THC on the cardiovascular system of endotoxemic rats. In our 24-hour endotoxemic rat model (E. coli derived lipopolysaccharide, LPS i.v. 5mg/kg) with THC treatment (LPS+THC 10 mg/kg i.p.), we investigated cardiac function by echocariography and endothelium-dependent relaxation of the thoracic aorta by isometric force measurement compared to vehicle controls. To evaluate the molecular mechanism, we measured endothelial NOS and COX-2 density by immunohistochemistry; and determined the levels of cGMP, the oxidative stress marker 4-hydroxynonenal, the nitrative stress marker 3-nitrotyrosine, and poly(ADP-ribose) polymers. A decrease in end-systolic and end-diastolic ventricular volumes in the LPS group was observed, which was absent in LPS+THC animals. Endothelium-dependent relaxation was worsened by LPS but not in the LPS+THC group. LPS administration decreased the abundance of cannabinoid receptors. Oxidative-nitrative stress markers showed an increment, and cGMP, eNOS staining showed a decrement in response to LPS. THC only decreased the oxidative-nitrative stress but had no effect on cGMP and eNOS density. COX-2 staining was reduced by THC. We hypothesize that the reduced diastolic filling in the LPS group is a consequence of vascular dysfunction, preventable by THC. The mechanism of action of THC is not based on its local effect on aortic NO homeostasis. The reduced oxidative-nitrative stress and the COX-2 suggest the activation of an anti-inflammatory pathway.

Risk Estimation of Gestational Diabetes Mellitus in the First Trimester.

CONTEXT: There is no early, first-trimester risk estimation available to predict later (gestational week 24-28) gestational diabetes mellitus (GDM); however, it would be beneficial to start an early treatment to prevent the development of complications. OBJECTIVE: We aimed to identify early, first-trimester prediction markers for GDM. METHODS: The present case-control study is based on the study cohort of a Hungarian biobank containing biological samples and follow-up data from 2545 pregnant women. Oxidative-nitrative stress-related parameters, steroid hormone, and metabolite levels were measured in the serum/plasma samples collected at the end of the first trimester from 55 randomly selected control and 55 women who developed GDM later. RESULTS: Pregnant women who developed GDM later during the pregnancy were older and had higher body mass index. The following parameters showed higher concentration in their serum/plasma samples: fructosamine, total antioxidant capacity, testosterone, cortisone, 21-deoxycortisol; soluble urokinase plasminogen activator receptor, dehydroepiandrosterone sulfate, dihydrotestosterone, cortisol, and 11-deoxycorticosterone levels were lower. Analyzing these variables using a forward stepwise multivariate logistic regression model, we established a GDM prediction model with a specificity of 96.6% and sensitivity of 97.5% (included variables: fructosamine, cortisol, cortisone, 11-deoxycorticosterone, SuPAR). CONCLUSION: Based on these measurements, we accurately predict the development of later-onset GDM (24th-28th weeks of pregnancy). Early risk estimation provides the opportunity for targeted prevention and the timely treatment of GDM. Prevention and slowing the progression of GDM result in a lower lifelong metabolic risk for both mother and offspring.

Impact of Sex and Exercise on Femoral Artery Function: More Favorable Adaptation in Male Rats.

Blood flow increases in arteries of the skeletal muscles involved in active work. Our aim was to investigate the gender differences as a result of adaptation to sport in the femoral arteries. Vascular reactivity and histology of animals were compared following a 12-week swimming training. Animals were divided into sedentary male (MS), trained male (MTr), sedentary female (FS), and trained female (FTr) groups. Isolated femoral artery rings were examined by wire myography. Contraction induced by phenylephrine (Phe) did not differ between the four groups. The contractile ability in the presence of indomethacin (INDO) was decreased in both sedentary groups. However, we found a specific cyclooxygenase-2 (COX-2) role only in FS rats. After exercise training, we observed increased vasoconstriction in both sexes, when nitro-L-arginine methyl ester (L-NAME) was present. The COX-dependent vasoconstriction effect disappeared in MTr animals, and the COX-2-dependent vasoconstriction effect disappeared in FTr ones. Relaxation was reduced significantly, when L-NAME was present in MTr animals compared to in FTr rats. The training was associated with greater endothelial nitric oxide synthase (eNOS) protein expression in males, but not in females. The present study proves that there are gender differences regarding adaptation mechanisms of musculocutaneous arteries to sports training. In males, relaxation reserve capacity was markedly elevated compared to in females.

Galactomannans are the most effective soluble dietary fibers in type 2 diabetes: a systematic review and network meta-analysis.

BACKGROUND: Soluble dietary fibers are known to reduce the levels of blood glucose and lipids in patients with type 2 diabetes mellitus (type 2 diabetes). Although several different dietary fiber supplements are utilized, to our knowledge, no previous study has ranked their efficacy yet. OBJECTIVES: We performed this systematic review and network meta-analysis to rank the effects of different types of soluble dietary fibers. METHODS: We performed our last systematic search on November 20, 2022. Eligible randomized controlled trials (RCTs) included adult patients with type 2 diabetes and compared the intake of soluble dietary fibers with that of another type of dietary fiber or no fiber. The outcomes were related to glycemic and lipid levels. The Bayesian method was used to perform a network meta-analysis and calculate the surface under the cumulative ranking (SUCRA) curve values to rank the interventions. The Grading of Recommendations Assessment, Development, and Evaluation system was applied to evaluate the overall quality of the evidence. RESULTS: We identified 46 RCTs, including data from 2685 patients who received 16 types of dietary fibers as intervention. Galactomannans had the highest effect on reducing the levels of HbA1c (SUCRA: 92.33%) and fasting blood glucose (SUCRA: 85.92%). With regard to fasting insulin level, HOMA-IR, ß-glucans (SUCRA: 73.45%), and psyllium (SUCRA: 96.67%) were the most effective interventions. Galactomannans were ranked first in reducing the levels of triglycerides (SUCRA: 82.77%) and LDL cholesterol (SUCRA: 86.56%). With regard to cholesterol and HDL cholesterol levels, xylo-oligosaccharides (SUCRA: 84.59%) and gum arabic (SUCRA: 89.06%) were the most effective fibers. Most comparisons had a low or moderate certainty of evidence. CONCLUSIONS: Galactomannans were the most effective dietary fiber for reducing the levels of HbA1c, fasting blood glucose, triglycerides, and LDL cholesterol in patients with type 2 diabetes. This study was registered at PROSPERO as ID CRD42021282984.

Inositol is an effective and safe treatment in polycystic ovary syndrome: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Metformin is the gold standard insulin sensitizer, which is widely used to treat insulin resistance in polycystic ovary syndrome (PCOS). However, metformin may induce gastrointestinal side effects. OBJECTIVE: Inositols have long been debated as a potential alternative for metformin in treating PCOS. Therefore, the present systematic review aimed to evaluate the efficacy and safety of inositols in treating PCOS. METHODS: The present systematic search was performed in CENTRAL, MEDLINE, and Embase from the inception until October 20th, 2021. Eligible randomized controlled trials (RCTs) included women diagnosed with PCOS and compared any inositols with metformin or placebo. Our primary outcome was cycle normalization, whereas secondary outcomes were body mass index (BMI), parameters of carbohydrate metabolism and clinical and laboratory hyperandrogenism. Results are reported as risk ratios or mean differences (MDs) with 95% confidence intervals (CIs). RESULTS: Twenty-six RCTs were identified, including data of 1691 patients (806 inositol, 311 with placebo, and 509 metformin groups). In patients treated with inositols, the risk (CI: 1.13; 2.85) of having a regular menstrual cycle was found by 1.79 higher than in the case of placebo. Moreover, the inositols showed non-inferiority compared to metformin in this outcome. In the case of BMI (MD = -0.45; CI: -0.89; -0.02), free testosterone (MD = -0,41, CI: -0.69; -0.13), total testosterone (MD = -20.39, CI: -40.12; -0.66), androstenedione (MD = -0.69, CI: -1,16; -0.22), glucose (MD = -3.14; CI: -5.75; -0.54) levels and AUC insulin (MD = -2081.05, CI: -2745.32; -1416.78) inositol treatment induced greater decrease compared to placebo. Inositol increased sex-hormone-binding globulin significantly compared to placebo (MD = 32.06, CI:1.27; 62.85). CONCLUSION: Inositol is an effective and safe treatment in PCOS. Moreover, inositols showed non-inferiority in most outcomes compared to the gold standard treatment; metformin. TRIAL REGISTRATION: PROSPERO registration number: CRD42021283275.

The provenance of the raw material and the manufacturing technology of copper artefacts from the Copper Age hoard from Magyaregres, Hungary.

In 2016, a Stollhof-type copper hoard was found during an excavation in Magyaregres, Hungary. It was placed in a cooking pot, and deposited upside down within the boundaries of an Early Copper Age settlement. Similar hoards dating to the end of the 5th millennium BCE are well-known from Central Europe, however, this hoard represents the only one so far with thoroughly documented finding circumstances. The hoard contained 681 pieces of copper, 264 pieces of stone and a single Spondylus bead, along with 19 pieces of small tubular spiral copper coils, three spiral copper bracelets, and two large, spectacle spiral copper pendants. Until now, information on the provenance of raw materials and how such copper artefacts were manufactured has not been available. The artefacts were studied under optical microscopes to reveal the manufacturing process. Trace elemental composition (HR-ICP-MS) and lead isotope ratios (MC-ICP-MS) were measured to explore the provenance of raw materials. The ornaments were rolled or folded and coiled from thin sheets of copper using fahlore copper probably originating from the Northwestern Carpathians. A complex archaeological approach was employed to reveal the provenance, distribution and the social roles the ornaments could have played in the life of a Copper Age community. Evidence for local metallurgy was lacking in contemporaneous Transdanubian sites, therefore it is likely that the items of the hoard were manufactured closer to the raw material source, prior to being transported to Transdanubia as finished products. The method of deposition implies that such items were associated with special social contexts, represented exceptional values, and the context of deposition was also highly prescribed. The Magyaregres hoard serves as the first firm piece of evidence for the existence of a typologically independent Central European metallurgical circle which exploited the raw material sources located within its distribution.

Accurate Quantitative Histomorphometric-Mathematical Image Analysis Methodology of Rodent Testicular Tissue and Its Possible Future Research Perspectives in Andrology and Reproductive Medicine.

Infertility is increasing worldwide; male factors can be identified in nearly half of all infertile couples. Histopathologic evaluation of testicular tissue can provide valuable information about infertility; however, several different evaluation methods and semi-quantitative score systems exist. Our goal was to describe a new, accurate and easy-to-use quantitative computer-based histomorphometric-mathematical image analysis methodology for the analysis of testicular tissue. On digitized, original hematoxylin-eosin (HE)-stained slides (scanned by slide-scanner), quantitatively describable characteristics such as area, perimeter and diameter of testis cross-sections and of individual tubules were measured with the help of continuous magnification. Immunohistochemically (IHC)-stained slides were digitized with a microscope-coupled camera, and IHC-staining intensity measurements on digitized images were also taken. Suggested methods are presented with mathematical equations, step-by-step detailed characterization and representative images are given. Our novel quantitative histomorphometric-mathematical image analysis method can improve the reproducibility, objectivity, quality and comparability of andrological-reproductive medicine research by recognizing even the mild impairments of the testicular structure expressed numerically, which might not be detected with the present semi-quantitative score systems. The technique is apt to be subjected to further automation with machine learning and artificial intelligence and can be named 'Computer-Assisted or -Aided Testis Histology' (CATHI).

Sex differences in rat renal arterial responses following exercise training.

During aerobic exercise, hemodynamic alterations occur. Although blood flow in skeletal muscle arteries increases, it decreases in visceral vessels because of mesenterial vasoconstriction. However, maintaining renal blood flow during intensive sport is also a priority. Our aim was to investigate the changes of vascular reactivity and histology of isolated renal artery of male and female rats in response to swim training. Wistar rats were distributed into four groups: male sedentary (MSed), male trained (MTr), female sedentary (FSed), and female trained (FTr). Trained animals underwent a 12-wk-long intensive swimming program. Vascular function of isolated renal artery segments was examined by wire myography. Phenylephrine-induced contraction was lower in FSed than in MSed animals, and it was decreased by training in male but not in female animals. Inhibition of cyclooxygenases by indomethacin reduced contraction in both sedentary groups, and in MTr but not in FTr animals. Inhibition of nitric oxide production increased contraction in both trained groups. Acetylcholine induced relaxation was similar in all experimental groups showing predominant NO-dependency. Elastin and smooth muscle cell actin density was reduced in female rats after aerobic training. This study shows that, as a result of a 12-wk-long training, there are sex differences in renal arterial responses following exercise training. Swimming moderates renal artery vasoconstriction in male animals, whereas it depresses elastic fiber and smooth muscle actin density in females.NEW & NOTEWORTHY We provided the first detailed analysis of the adaptation of the renal artery after aerobic training in male and female rats. As a result of a 12-wk-long training program, the pharmacological responses of renal arteries changed only in male animals. In phenylephrine-induced contraction, cyclooxygenase-mediated vasoconstriction mechanisms lost their significance in female rats, whereas NO-dependent relaxation became a significant contraction reducing factor in both sexes. Early structural changes, such as reduced elastin and smooth muscle cell actin evolves in females.

Sustainable Stabilizer-Free Nanoparticle Formulations of Valsartan Using Eudragit® RLPO.

The bioavailability of the antihypertensive drug valsartan can be enhanced by various microencapsulation methods. In the present investigation, valsartan-loaded polymeric nanoparticles were manufactured from Eudragit® RLPO using an emulsion-solvent evaporation method. Polyvinyl alcohol (PVA) was found to be a suitable stabilizer for the nanoparticles, resulting in a monodisperse colloid system ranging in size between 148 nm and 162 nm. Additionally, a high encapsulation efficiency (96.4%) was observed. However, due to the quaternary ammonium groups of Eudragit® RLPO, the stabilization of the dispersion could be achieved in the absence of PVA as well. The nanoparticles were reduced in size (by 22%) and exhibited similar encapsulation efficiencies (96.4%). This more cost-effective and sustainable production method reduces the use of excipients and their expected emission into the environment. The drug release from valsartan-loaded nanoparticles was evaluated in a two-stage biorelevant dissolution set-up, leading to the rapid dissolution of valsartan in a simulated intestinal medium. In silico simulations using a model validated previously indicate a potential dose reduction of 60-70% compared to existing drug products. This further reduces the expected emission of the ecotoxic compound into the environment.

Influence of Vitamin D on the Vasoactive Effect of Estradiol in a Rat Model of Polycystic Ovary Syndrome.

We examined the vasoactive effect of estradiol in a rat model of early PCOS and the influence of vitamin D deficiency (VDD). We created a model of chronic hyperandrogenism and VDD in adolescent female Wistar rats (N = 46) with four experimental groups: vitamin D supplemented (T-D+), VDD (T-D-), hyperandrogenic and vitamin D supplemented (T+D+), and hyperandrogenic and VDD (T+D-). T+ groups received an 8-week-long transdermal Androgel treatment, D-animals were on vitamin D-reduced diet and D+ rats were supplemented orally with vitamin D3. Estrogen-induced vasorelaxation of thoracic aorta segments were measured with a wire myograph system with or without the inhibition of endothelial nitric oxide synthase (eNOS) or cyclooxygenase-2 (COX-2). The distribution of estrogen receptor (ER), eNOS and COX-2 in the aortic wall was assessed by immunohistochemistry. VDD aortas showed significantly lower estradiol-induced relaxation independently of androgenic status that was further decreased by COX-2 inhibition. COX-2 inhibition failed to alter vessel function in D+ rats. Inhibition of eNOS abolished the estradiol-induced relaxation in all groups. Changes in vascular function in VDD were accompanied by significantly decreased ER and eNOS staining. Short-term chronic hyperandrogenism failed to, but VDD induced vascular dysfunction, compromised estrogen-dependent vasodilatation and changes in ER and eNOS immunostaining.

Vitamin D Deficiency and Gender Alter Vasoconstrictor and Vasodilator Reactivity in Rat Carotid Artery.

The vitamin-D-sensitivity of the cardiovascular system may show gender differences. The prevalence of vitamin D (VD) deficiency (VDD) is high, and it alters cardiovascular function and increases the risk of stroke. Our aim was to investigate the vascular reactivity and histological changes of isolated carotid artery of female and male rats in response to different VD supplies. A total of 48 male and female Wistar rats were divided into four groups: female VD supplemented, female VDD, male VD supplemented, male VDD. The vascular function of isolated carotid artery segments was examined by wire myography. Both vitamin D deficiency and male gender resulted in increased phenylephrine-induced contraction. Acetylcholine-induced relaxation decreased in male rats independently from VD status. Inhibition of prostanoid signaling by indomethacin reduced contraction in females, but increased relaxation ability in male rats. Functional changes were accompanied by VDD and gender-specific histological alterations. Elastic fiber density was significantly decreased by VDD in female rats, but not in males. Smooth muscle actin and endothelial nitric oxide synthase levels were significantly lowered, but the thromboxane receptor was elevated in VDD males. Decreased nitrative stress was detected in both male groups independently from VD supply. The observed interactions between vitamin D deficiency and sex may play a role in the gender difference of cardiovascular risk.

Left Ventricular SGLT1 Protein Expression Correlates with the Extent of Myocardial Nitro-Oxidative Stress in Rats with Pressure and Volume Overload-Induced Heart Failure.

Myocardial sodium-glucose cotransporter 1 (SGLT1) has been shown to be upregulated in humans with heart failure (HF) with or without diabetes. In vitro studies have linked SGLT1 to increased nitro-oxidative stress in cardiomyocytes. We aimed to assess the relation between left ventricular (LV) SGLT1 expression and the extent of nitro-oxidative stress in two non-diabetic rat models of chronic heart failure (HF) evoked by either pressure (TAC, n = 12) or volume overload (ACF, n = 12). Sham-operated animals (Sham-T and Sham-A, both n = 12) served as controls. Both TAC and ACF induced characteristic LV structural and functional remodeling. Western blotting revealed that LV SGLT1 protein expression was significantly upregulated in both HF models (both p < 0.01), whereas the phosphorylation of ERK1/2 was decreased only in ACF; AMPKα activity was significantly reduced in both models. The protein expression of the Nox4 NADPH oxidase isoform was increased in both TAC and ACF compared with respective controls (both p < 0.01), showing a strong positive correlation with SGLT1 expression (r = 0.855, p < 0.001; and r = 0.798, p = 0.001, respectively). Furthermore, SGLT1 protein expression positively correlated with the extent of myocardial nitro-oxidative stress in failing hearts assessed by 3-nitrotyrosin (r = 0.818, p = 0.006) and 4-hydroxy-2-nonenal (r = 0.733, p = 0.020) immunostaining. Therefore, LV SGLT1 protein expression was upregulated irrespective of the nature of chronic hemodynamic overload, and correlated significantly with the expression of Nox4 and with the level of myocardial nitro-oxidative stress, suggesting a pathophysiological role of SGLT1 in HF.

Sex Differences in Exercise-Training-Related Functional and Morphological Adaptation of Rat Gracilis Muscle Arterioles.

BACKGROUND: The cardiovascular effects of training have been widely investigated; however, few studies have addressed sex differences in arteriolar adaptation. In the current study, we examined the adaptation of the gracilis arterioles of male and female rats in response to intensive training. METHODS: Wistar rats were divided into four groups: male exercise (ME) and female exercise (FE) animals that underwent a 12-week intensive swim-training program (5 days/week, 200 min/day); and male control (MC) and female control (FC) animals that were placed in water for 5 min daily. Exercise-induced cardiac hypertrophy was confirmed by echocardiography. Following the training, the gracilis muscle arterioles were prepared, and their biomechanical properties and functional reactivity were tested, using pressure arteriography. Collagen and smooth muscle remodeling were observed in the histological sections. RESULTS: Left ventricular mass was elevated in both sexes in response to chronic training. In the gracilis arterioles, the inner radius and wall tension increased in female animals, and the wall thickness and elastic modulus were reduced in males. Myogenic tone was reduced in the ME group, whereas norepinephrine-induced vasoconstriction was elevated in the FE group. More pronounced collagen staining was observed in the ME group than in the MC group. Relative hypertrophy and tangential stress of the gracilis arterioles were higher in females than in males. The direct vasoconstriction induced by testosterone was lower in females and was reduced as an effect of exercise in males. CONCLUSION: The gracilis muscle arteriole was remodeled as a result of swim training, and this adaptation was sex dependent.

Vitamin D Deficiency Reduces Vascular Reactivity of Coronary Arterioles in Male Rats.

BACKGROUND: Vitamin D deficiency (VDD) may be considered an independent cardiovascular (CV) risk factor, and it is well known that CV risk is higher in males. Our goal was to investigate the pharmacological reactivity and receptor expression of intramural coronary artery segments of male rats in cases of different vitamin D supply. METHODS: Four-week-old male Wistar rats were divided into a control group (n = 11) with optimal vitamin D supply (300 IU/kgbw/day) and a VDD group (n = 11, <0.5 IU/kgbw/day). After 8 weeks of treatment, intramural coronary artery segments were microprepared, their pharmacological reactivity was examined by in vitro microangiometry, and their receptor expression was investigated by immunohistochemistry. RESULTS: Thromboxane A2 (TXA2)-agonist induced reduced vasoconstriction, testosterone (T) and 17-ß-estradiol (E2) relaxations were significantly decreased, a significant decrease in thromboxane receptor (TP) expression was shown, and the reduction in estrogen receptor-α (ERα) expression was on the border of significance in the VDD group. CONCLUSIONS: VD-deficient male coronary arteries showed deteriorated pharmacological reactivity to TXA2 and sexual steroids (E2, T). Insufficient vasoconstrictor capacity was accompanied by decreased TP receptor expression, and vasodilator impairments were mainly functional. The decrease in vasoconstrictor and vasodilator responses results in narrowed adaptational range of coronaries, causing inadequate coronary perfusion that might contribute to the increased CV risk in VDD.

Network analysis of the left anterior descending coronary arteries in swim-trained rats by an in situ video microscopic technique.

BACKGROUND: We aimed to identify sex differences in the network properties and to recognize the geometric alteration effects of long-term swim training in a rat model of exercise-induced left ventricular (LV) hypertrophy. METHODS: Thirty-eight Wistar rats were divided into four groups: male sedentary, female sedentary, male exercised and female exercised. After training sessions, LV morphology and function were checked by echocardiography. The geometry of the left coronary artery system was analysed on pressure-perfused, microsurgically prepared resistance artery networks using in situ video microscopy. All segments over > 80 µm in diameter were studied using divided 50-µm-long cylindrical ring units of the networks. Oxidative-nitrative (O-N) stress markers, adenosine A2A and estrogen receptor (ER) were investigated by immunohistochemistry. RESULTS: The LV mass index, ejection fraction and fractional shortening significantly increased in exercised animals. We found substantial sex differences in the coronary network in the control groups and in the swim-trained animals. Ring frequency spectra were significantly different between male and female animals in both the sedentary and trained groups. The thickness of the wall was higher in males as a result of training. There were elevations in the populations of 200- and 400-µm vessel units in males; the thinner ones developed farther and the thicker ones closer to the orifice. In females, a new population of 200- to 250-µm vessels appeared unusually close to the orifice. CONCLUSIONS: Physical activity and LV hypertrophy were accompanied by a remodelling of coronary resistance artery network geometry that was different in both sexes.