Osthole Prevents Heart Damage Induced by Diet-Induced Metabolic Syndrome: Role of Fructokinase (KHK).

There is increasing evidence that either ingested or produced fructose may have a role in metabolic syndrome. While not commonly considered a criterion for metabolic syndrome, cardiac hypertrophy is often associated with metabolic syndrome, and its presence carries increased cardiovascular risk. Recently it has been shown that fructose and fructokinase C (KHK) can be induced in cardiac tissue. Here we tested whether diet-induced metabolic syndrome causes heart disease associated with increased fructose content and metabolism and whether it can be prevented with a fructokinase inhibitor (osthole). Male Wistar rats were provided a control diet (C) or high fat/sugar diet for 30 days (MS), with half of the latter group receiving osthol (MS+OT, 40 mg/kg/d). The Western diet increased fructose, uric acid, and triglyceride concentrations in cardiac tissue associated with cardiac hypertrophy, local hypoxia, oxidative stress, and increased activity and expression of KHK in cardiac tissue. Osthole reversed these effects. We conclude that the cardiac changes in metabolic syndrome involve increased fructose content and its metabolism and that blocking fructokinase can provide cardiac benefit through the inhibition of KHK with modulation of hypoxia, oxidative stress, hypertrophy, and fibrosis.

Self-reported dietary omega-3 polyunsaturated fatty acids are associated with adipose tissue markers and glucose metabolism in apparently healthy subjects.

BACKGROUND: Plasminogen activator inhibitor 1 (PAI-1) and resistin are associated with dysfunctional adipose tissue (AT)-related metabolic complications. The role of dietary eicosapentaenoic (EPA) and docosahexaenoic (DHA) fatty acids in this relationship is unknown. AIM: To investigate the association of EPA and DHA with PAI-1 and resistin, as well as the role of this association on the glucose metabolism of apparently healthy subjects. SUBJECTS AND METHODS: Thirty-six healthy individuals were included. Validated food frequency questionnaires were used to analyse dietary habits. Inflammatory and glucose metabolism markers were quantified. Subcutaneous AT samples were obtained, and adipocyte number, area, and macrophage content were assessed. RESULTS: In 36 subjects aged 56 ± 8 years and with a body mass index of 26 ± 4 kg/m2, logEPA, and logDHA showed significant association with logresistin and a marginal association with PAI-1. Adipocyte number, area, and lognumber of macrophages per adipocyte significantly correlated with PAI-1 but not with logresistin. Although logEPA and logDHA were independently associated with loginsulin, loginsulin resistance, and C-Peptide, the addition of logresistin, but not of PAI-1, into the multivariable model, abolished the associations. CONCLUSIONS: EPA and DHA could modulate glucose metabolism across AT functional states. Our data indicate that this association is independent of other metabolic risk factors.

Mecanismos moleculares de los efectos benéficos de la alicina sobre la enfermedad cardiovascular / Molecular mechanisms of the beneficial effects of allicin on cardiovascular disease

Resumen Las enfermedades cardiovasculares (ECV) comprenden un grupo de enfermedades cuyo denominador común es la afectación de vasos sanguíneos, corazón y ritmo cardiaco. El tratamiento de las ECV representa costos muy altos para los sistemas de salud y está enfocado en el control de los factores de riesgo. A pesar de existir una gran variedad de fármacos para el tratamiento de las ECV, estas continúan siendo las principales causas de mortalidad, posiblemente debido a que su origen es multifactorial y por ello se requiere de más de un fármaco. En este contexto, la alicina, un compuesto derivado del ajo, ha mostrado regular la expresión de vías de señalización y factores de riesgo asociados a la progresión de las ECV. Por ello el objetivo del presente trabajo es revisar los mecanismos celulares y moleculares por medio de los cuales la alicina ejerce sus efectos terapéuticos y describir las evidencias científicas del porqué la alicina podría representar un potencial candidato para coadyuvar en el tratamiento de las ECV.

Abstract Cardiovascular diseases (CVD) include a group of diseases whose common denominator is the affection of the blood vessels, heart, and heart rate. The treatment of CVD represents high costs to the health systems and is focused on the control of risk factors. Despite the existence of a great variety of treatments of the CVD, these continue as the main cause of mortality mainly due to the multifactorial origin, and therefore more than one drug is required. In this context, allicin, a compound derived from garlic, has shown regulate the expression of signaling pathways and risk factors associated with the progression of CVD. Therefore, the objective of this work is to review the cellular and molecular mechanisms through which allicin exert its therapeutic effects and to describe the scientific evidences why allicin represents a potential candidate to assist in the treatment of CVD.

Cellular Mechanisms Underlying the Cardioprotective Role of Allicin on Cardiovascular Diseases.

Cardiovascular diseases (CVDs) are a group of diseases in which the common denominator is the affection of blood vessels, heart tissue, and heart rhythm. The genesis of CVD is complex and multifactorial; therefore, approaches are often based on multidisciplinary management and more than one drug is used to achieve the optimal control of risk factors (dyslipidemia, hypertension, hypertrophy, oxidative stress, endothelial dysfunction, inflammation). In this context, allicin, a sulfur compound naturally derived from garlic, has shown beneficial effects on several cardiovascular risk factors through the modulation of cellular mechanisms and signaling pathways. Effective pharmacological treatments for CVD or its risk factors have not been developed or are unknown in clinical practice. Thus, this work aimed to review the cellular mechanisms through which allicin exerts its therapeutic effects and to show why it could be a therapeutic option for the prevention or treatment of CVD and its risk factors.

Mecanismos moleculares de los efectos benéficos de la alicina sobre la enfermedad cardiovascular.

Las enfermedades cardiovasculares (ECV) comprenden un grupo de enfermedades cuyo denominador común es la afectación de vasos sanguíneos, corazón y ritmo cardiaco. El tratamiento de las ECV representa costos muy altos para los sistemas de salud y está enfocado en el control de los factores de riesgo. A pesar de existir una gran variedad de fármacos para el tratamiento de las ECV, estas continúan siendo las principales causas de mortalidad, posiblemente debido a que su origen es multifactorial y por ello se requiere de más de un fármaco. En este contexto, la alicina, un compuesto derivado del ajo, ha mostrado regular la expresión de vías de señalización y factores de riesgo asociados a la progresión de las ECV. Por ello el objetivo del presente trabajo es revisar los mecanismos celulares y moleculares por medio de los cuales la alicina ejerce sus efectos terapéuticos y describir las evidencias científicas del porqué la alicina podría representar un potencial candidato para coadyuvar en el tratamiento de las ECV.Cardiovascular diseases (CVD) include a group of diseases whose common denominator is the affection of the blood vessels, heart, and heart rate. The treatment of CVD represents high costs to the health systems and is focused on the control of risk factors. Despite the existence of a great variety of treatments of the CVD, these continue as the main cause of mortality mainly due to the multifactorial origin, and therefore more than one drug is required. In this context, allicin, a compound derived from garlic, has shown regulate the expression of signaling pathways and risk factors associated with the progression of CVD. Therefore, the objective of this work is to review the cellular and molecular mechanisms through which allicin exert its therapeutic effects and to describe the scientific evidences why allicin represents a potential candidate to assist in the treatment of CVD.

Uric acid is associated with morpho-functional adipose tissue markers in apparently healthy subjects.

BACKGROUND: Studies have focused on the search of novel biomarkers that allow to easily identify dysfunctional adipose tissue (AT). Uric acid (UA) could be produced and reabsorbed by AT. It has been suggested that the increases of UA concentrations participates in AT dysfunction. We investigated the association of UA with morpho-functional adipose tissue markers in apparently healthy subjects. METHODS: Forty apparently healthy individuals were included. Dietary habits and anthropometrical features were evaluated. Circulating concentrations of UA, adiponectin, leptin, and plasminogen activator inhibitor-1 (PAI-1) were quantified. Periumbilical subcutaneous AT samples were obtained and adipocyte number, adipocyte area, and macrophages content were assessed. RESULTS: The present study included 40 healthy subjects (67% women) with an average age of 57 ± 9 y, BMI of 26 ± 4 (kg/m2). UA showed a significant association with the number and mean area of adipocytes, macrophages number, adiponectin, and PAI-1. Although UA was independently associated with the number and mean area of adipocytes, macrophages number, adiponectin into the adjusted multivariable model. CONCLUSION: UA concentrations are associated with morpho-functional adipose tissue markers. Our results underscore the importance of UA as one earlier instigator of adipose tissue dysfunction in subjects without metabolic abnormalities.

Anti-Inflammatory Effect of Allicin Associated with Fibrosis in Pulmonary Arterial Hypertension.

Pulmonary arterial hypertension (PAH) is characterized by pulmonary vascular remodeling. Recent evidence supports that inflammation plays a key role in triggering and maintaining pulmonary vascular remodeling. Recent studies have shown that garlic extract has protective effects in PAH, but the precise role of allicin, a compound derived from garlic, is unknown. Thus, we used allicin to evaluate its effects on inflammation and fibrosis in PAH. Male Wistar rats were divided into three groups: control (CON), monocrotaline (60 mg/kg) (MCT), and MCT plus allicin (16 mg/kg/oral gavage) (MCT + A). Right ventricle (RV) hypertrophy and pulmonary arterial medial wall thickness were determined. IL-1ß, IL-6, TNF-α, NFκB p65, Iκß, TGF-ß, and α-SMA were determined by Western blot analysis. In addition, TNF-α and TGF-ß were determined by immunohistochemistry, and miR-21-5p and mRNA expressions of Cd68, Bmpr2, and Smad5 were determined by RT-qPCR. Results: Allicin prevented increases in vessel wall thickness due to TNF-α, IL-6, IL-1ß, and Cd68 in the lung. In addition, TGF-ß, α-SMA, and fibrosis were lower in the MCT + A group compared with the MCT group. In the RV, allicin prevented increases in TNF-α, IL-6, and TGF-ß. These observations suggest that, through the modulation of proinflammatory and profibrotic markers in the lung and heart, allicin delays the progression of PAH.

Osthol Ameliorates Kidney Damage and Metabolic Syndrome Induced by a High-Fat/High-Sugar Diet.

Excessive intake of fructose results in metabolic syndrome (MS) and kidney damage, partly mediated by its metabolism by fructokinase-C or ketohexokinase-C (KHK-C). Osthol has antioxidant properties, is capable of regulating adipogenesis, and inhibits KHK-C activity. Here, we examined the potential protective role of osthol in the development of kidney disease induced by a Western (high-fat/high-sugar) diet. Control rats fed with a high-fat/high-sugar diet were compared with two groups that also received two different doses of osthol (30 mg/kg/d or 40 mg/kg/d body weight BW). A fourth group served as a normal control and received regular chow. At the end of the follow-up, kidney function, metabolic markers, oxidative stress, and lipogenic enzymes were evaluated. The Western diet induced MS (hypertension, hyperglycemia, hypertriglyceridemia, obesity, hyperuricemia), a fall in the glomerular filtration rate, renal tubular damage, and increased oxidative stress in the kidney cortex, with increased expression of lipogenic enzymes and increased kidney KHK expression. Osthol treatment prevented the development of MS and ameliorated kidney damage by inhibiting KHK activity, preventing oxidative stress via nuclear factor erythroid 2-related factor (Nrf2) activation, and reducing renal lipotoxicity. These data suggest that the nutraceutical osthol might be an ancillary therapy to slow the progression of MS and kidney damage induced by a Western diet.

Fluid Intake Restriction Concomitant to Sweetened Beverages Hydration Induce Kidney Damage.

Currently, there is the paradox of low water intake but increased intake of sugar-sweetened beverages (SB) in several populations; those habits are associated with an increased prevalence of metabolic derangements and greater chronic disease mortality. Persistent heat dehydration and increased SB intake stimulate the continued release of vasopressin and overactivation of the polyol-fructokinase pathway, synergizing each other, an effect partially mediated by oxidative stress. The objective of the present study was to evaluate whether water restriction concurrent with SB hydration can cause renal damage by stimulating similar pathways as heat dehydration. Three groups of male Wistar rats (n = 6) were fluid restricted; from 10 am to 12 pm animals could rehydrate with tap water (W), or sweetened beverages, one prepared with 11% of a fructose-glucose combination (SB), or with the noncaloric edulcorant stevia (ST). A normal control group of healthy rats was also studied. The animals were followed for 4 weeks. Markers of dehydration and renal damage were evaluated at the end of the study. Fluid restriction and water hydration mildly increased urine osmolality and induced a 15% fall in CrCl while increased the markers of tubular damage by NAG and KIM-1. Such changes were in association with a mild overexpression of V1a and V2 renal receptors, polyol fructokinase pathway overactivation, and increased renal oxidative stress with reduced expression of antioxidant enzymes. Hydration with SB significantly amplified those alterations, while in stevia hydrated rats, the changes were similar to the ones observed in water hydrated rats. These data suggest that current habits of hydration could be a risk factor in developing kidney damage.

Nutraceuticals in the Treatment of Pulmonary Arterial Hypertension.

Pulmonary arterial hypertension (PAH) is a severe disease characterized by the loss and obstructive remodeling of the pulmonary arterial wall, causing a rise in pulmonary arterial pressure and pulmonary vascular resistance, which is responsible for right heart failure, functional decline, and death. Although many drugs are available for the treatment of this condition, it continues to be life-threatening, and its long-term treatment is expensive. On the other hand, many natural compounds present in food have beneficial effects on several cardiovascular conditions. Several studies have explored many of the potential beneficial effects of natural plant products on PAH. However, the mechanisms by which natural products, such as nutraceuticals, exert protective and therapeutic effects on PAH are not fully understood. In this review, we analyze the current knowledge on nutraceuticals and their potential use in the protection and treatment of PAH, as well as whether nutraceuticals could enhance the effects of drugs used in PAH through similar mechanisms.

Control of blood pressure levels in patients with premature coronary artery disease: Results from the Genetics of Atherosclerotic Disease study.

High blood pressure (BP) is the major cardiovascular-risk factor for coronary artery disease (CAD), principally in young patients who have an important and increasing socioeconomic burden. Despite the Seventh Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC-7), recommended BP target <140/90 mm Hg for patients with stable CAD, in 2017 the American College of Cardiology and the American Heart Association (ACC/AHA) updated BP target to <130/80 mm Hg. We aimed to analyze the prevalence of BP control in patients with premature CAD using both criteria. In addition, antihypertensive therapy, lifestyle, clinical, and sociodemographic characteristics of the patients were evaluated in order to identify factors associated with the achievement of BP targets. The present study included 1206 patients with CAD diagnosed before 55 and 65 years old in men and women, respectively. Sociodemographic, clinical, and biochemical data were collected. The results indicate that 85.6% and 77.5% of subjects with premature CAD achieved JNC-7 non-strict and ACC/AHA strict BP target, respectively. Consistently, number of antihypertensive drugs and hypertension duration >10 years were inversely associated with BP targets, whereas total physical activity and smoking were directly associated with BP targets, regardless of BP criteria. Considering that age, gender, and hypertension duration are non-modifiable cardiovascular-risk factors, our results highlight the need for more effective strategies focused on increase physical activity and smoking cessation in young patients with CAD. These healthier lifestyles changes should favor the BP target achievement and reduce the socioeconomic and clinical burden of premature CAD.

Vasopressin Mediates the Renal Damage Induced by Limited Fructose Rehydration in Recurrently Dehydrated Rats.

Recurrent dehydration and heat stress cause chronic kidney damage in experimental animals. The injury is exacerbated by rehydration with fructose-containing beverages. Fructose may amplify dehydration-induced injury by directly stimulating vasopressin release and also by acting as a substrate for the aldose reductase-fructokinase pathway, as both of these systems are active during dehydration. The role of vasopressin in heat stress associated injury has not to date been explored. Here we show that the amplification of renal damage mediated by fructose in thermal dehydration is mediated by vasopressin. Fructose rehydration markedly enhanced vasopressin (copeptin) levels and activation of the aldose reductase-fructokinase pathway in the kidney. Moreover, the amplification of the renal functional changes (decreased creatinine clearance and tubular injury with systemic inflammation, renal oxidative stress, and mitochondrial dysfunction) were prevented by the blockade of V1a and V2 vasopressin receptors with conivaptan. On the other hand, there are also other operative mechanisms when water is used as rehydration fluid that produce milder renal damage that is not fully corrected by vasopressin blockade. Therefore, we clearly showed evidence of the cross-talk between fructose, even at small doses, and vasopressin that interact to amplify the renal damage induced by dehydration. These data may be relevant for heat stress nephropathy as well as for other renal pathologies due to the current generalized consumption of fructose and deficient hydration habits.

Effects of Allicin on Hypertension and Cardiac Function in Chronic Kidney Disease.

This work was performed to study the effect of allicin on hypertension and cardiac function in a rat model of CKD. The groups were control, CKD (5/6 nephrectomy), and CKD-allicin treated (CKDA) (40 mg/kg day/p.o.). Blood pressure was monitored (weekly/6 weeks). The cardiac function, vascular response to angiotensin II, oxidative stress, and heart morphometric parameters were determined. The CKD group showed hypertension and proteinuria. The coronary perfusion and left ventricular pressures were decreased in CKD group. In contrast, the vascular response to angiotensin II and expression of angiotensin II type 1 receptor (AT1R) were increased. These data were associated with the increment in morphometric parameters (weight of heart and left ventricle, heart/BW and left ventricular mass index, and wall thickness). Concurrently, the oxidative stress was increased and correlated inversely with the expression of Nrf2, Keap1, and antioxidant enzymes Nrf2-regulated. Allicin treatment attenuated hypertension and improved the renal and the cardiac dysfunctions; furthermore, it decreased the vascular reactivity to angiotensin II, AT1R overexpression, and preserved morphometric parameters. Allicin also downregulated Keap1 and increased Nrf2 expression, upregulated the antioxidant enzymes, and reduced oxidative stress. In conclusion, allicin showed an antihypertensive, nephroprotective, cardioprotective, and antioxidant effects, likely through downregulation of AT1R and Keap1 expression.

Rehydration with soft drink-like beverages exacerbates dehydration and worsens dehydration-associated renal injury.

Recurrent dehydration, such as commonly occurs with manual labor in tropical environments, has been recently shown to result in chronic kidney injury, likely through the effects of hyperosmolarity to activate both vasopressin and aldose reductase-fructokinase pathways. The observation that the latter pathway can be directly engaged by simple sugars (glucose and fructose) leads to the hypothesis that soft drinks (which contain these sugars) might worsen rather than benefit dehydration associated kidney disease. Recurrent dehydration was induced in rats by exposure to heat (36°C) for 1 h/24 h followed by access for 2 h to plain water (W), a 11% fructose-glucose solution (FG, same composition as typical soft drinks), or water sweetened with noncaloric stevia (ST). After 4 wk plasma and urine samples were collected, and kidneys were examined for oxidative stress, inflammation, and injury. Recurrent heat-induced dehydration with ad libitum water repletion resulted in plasma and urinary hyperosmolarity with stimulation of the vasopressin (copeptin) levels and resulted in mild tubular injury and renal oxidative stress. Rehydration with 11% FG solution, despite larger total fluid intake, resulted in greater dehydration (higher osmolarity and copeptin levels) and worse renal injury, with activation of aldose reductase and fructokinase, whereas rehydration with stevia water had opposite effects. In animals that are dehydrated, rehydration acutely with soft drinks worsens dehydration and exacerbates dehydration associated renal damage. These studies emphasize the danger of drinking soft drink-like beverages as an attempt to rehydrate following dehydration.

Renal oxidative stress induced by long-term hyperuricemia alters mitochondrial function and maintains systemic hypertension.

We addressed if oxidative stress in the renal cortex plays a role in the induction of hypertension and mitochondrial alterations in hyperuricemia. A second objective was to evaluate whether the long-term treatment with the antioxidant Tempol prevents renal oxidative stress, mitochondrial alterations, and systemic hypertension in this model. Long-term (11-12 weeks) and short-term (3 weeks) effects of oxonic acid induced hyperuricemia were studied in rats (OA, 750 mg/kg BW), OA+Allopurinol (AP, 150 mg/L drinking water), OA+Tempol (T, 15 mg/kg BW), or vehicle. Systolic blood pressure, renal blood flow, and vascular resistance were measured. Tubular damage (urine N-acetyl-ß-D-glucosaminidase) and oxidative stress markers (lipid and protein oxidation) along with ATP levels were determined in kidney tissue. Oxygen consumption, aconitase activity, and uric acid were evaluated in isolated mitochondria from renal cortex. Short-term hyperuricemia resulted in hypertension without demonstrable renal oxidative stress or mitochondrial dysfunction. Long-term hyperuricemia induced hypertension, renal vasoconstriction, tubular damage, renal cortex oxidative stress, and mitochondrial dysfunction and decreased ATP levels. Treatments with Tempol and allopurinol prevented these alterations. Renal oxidative stress induced by hyperuricemia promoted mitochondrial functional disturbances and decreased ATP content, which represent an additional pathogenic mechanism induced by chronic hyperuricemia. Hyperuricemia-related hypertension occurs before these changes are evident.