Taurine Supplementation Lowers Blood Pressure and Improves Vascular Function in Prehypertension: Randomized, Double-Blind, Placebo-Controlled Study

Circulating Bile Acid Profiles: A Need for Further Examination

CONTEXT

Bile acids (BAs) are increasingly recognized as metabolic and chronobiologic integrators that synchronize the systemic metabolic response to nutrient availability. Alterations in the concentration and/or composition of circulating BAs are associated with a number of metabolic disorders, such as obesity, type 2 diabetes mellitus (T2DM), insulin resistance (IR), and metabolic associated fatty liver disease (MAFLD). This review summarizes recent evidence that links abnormal circulating BA profiles to multiple metabolic disorders, and discusses the possible mechanisms underlying the connections to determine the role of BA profiling as a novel biomarker for these abnormalities.

EVIDENCE ACQUISITION

The review is based on a collection of primary and review literature gathered from a PubMed search of BAs, T2DM, IR, and MAFLD, among other keywords.

EVIDENCE SYNTHESIS

Obese and IR subjects appear to have elevated fasting circulating BAs but lower postprandial increase when compared with controls. The possible underlying mechanisms are disruption in the synchronization between the feeding/fasting cycle and the properties of BA-regulated metabolic pathways. Whether BA alterations are associated per se with MAFLD remains inconclusive. However, increased fasting circulating BAs level was associated with higher risk of advanced fibrosis stage. Thus, for patients with MAFLD, dynamically monitoring the circulating BA profiles may be a promising tool for the stratification of MAFLD.

CONCLUSIONS

Alterations in the concentration, composition, and rhythm of circulating BAs are associated with adverse events in systemic metabolism. Subsequent investigations regarding these aspects of circulating BA kinetics may help predict future metabolic disorders and guide therapeutic interventions.

The Efficacy of a Calamansi-Containing Energy Drink on Running Performance and Recovery in NCAA Division I Middle-Distance Runners: A Preliminary Study

This study examined the effects of a non-caffeinated energy drink (ED) that contained calamansi juice, glucose, and taurine on 3-km running performance and recovery. Eleven NCAA Division I middle-distance runners (20.8 ± 1.5 years old) were randomly assigned to consume either the ED or a placebo drink 60 min before 3-km running on a 400-m official track. Performance time and speed were recorded every 500-m interval. Recovery blood lactate concentration (BLC), systolic (SBP), diastolic blood pressure (DBP), and heart rate (HR) were measured at baseline, 60-min after ingesting the drinks, and post-running measurements were performed at 1-min, 5-min, and 10-min. Repeated analysis of variance and paired t-test were applied to examine the effects of time, trials, and their interaction on performance and recovery. Statistical significance was set a priori at p < 0.05. No significant difference was observed in performance time and speed between trials (p < 0.05). No interaction effect was found on performance time, speed, recovery BLC, DBP, and HR (p < 0.05). However, an interaction effect for trial by time was observed on SBP (p = 0.01). Recovery SBP continues to decrease from 5-min to 10-min in the ED trial (∆ = -13.9 mmHg) and slightly increased in the placebo trial (∆ = 1.1 mmHg). This study suggests that acute consumption of a calamansi-containing ED can positively impact the SBP recovery but not running performance. Further studies are needed to examine the acute and chronic effects of this ED on exercise performance and recovery among different populations.

Treatment-resistant schizophrenia: focus on the transsulfuration pathway

Treatment-resistant schizophrenia (TRS) is a severe form of schizophrenia. The severity of illness is positively related to homocysteine levels, with high homocysteine levels due to the low activity of the transsulfuration pathway, which metabolizes homocysteine in synthesizing L-cysteine. Glutathione levels are low in schizophrenia, which indicates shortages of L-cysteine and low activity of the transsulfuration pathway. Hydrogen sulfide (H2S) levels are low in schizophrenia. H2S is synthesized by cystathionine β-synthase and cystathionine γ-lyase, which are the two enzymes in the transsulfuration pathway. Iron-sulfur proteins obtain sulfur from L-cysteine. The oxidative phosphorylation (OXPHOS) pathway has various iron-sulfur proteins. With low levels of L-cysteine, iron-sulfur cluster formation will be dysregulated leading to deficits in OXPHOS in schizophrenia. Molybdenum cofactor (MoCo) synthesis requires sulfur, which is obtained from L-cysteine. With low levels of MoCo synthesis, molybdenum-dependent sulfite oxidase (SUOX) will not be synthesized at appropriate levels. SUOX detoxifies sulfite from sulfur-containing amino acids. If sulfites are not detoxified, there can be sulfite toxicity. The transsulfuration pathway metabolizes selenomethionine, whereby selenium from selenomethionine can be used for selenoprotein synthesis. The low activity of the transsulfuration pathway decreases selenoprotein synthesis. Glutathione peroxidase (GPX), with various GPXs being selenoprotein, is low in schizophrenia. The dysregulations of selenoproteins would lead to oxidant stress, which would increase the methylation of genes and histones leading to epigenetic changes in TRS. An add-on treatment to mainline antipsychotics is proposed for TRS that targets the dysregulations of the transsulfuration pathway and the dysregulations of other pathways stemming from the transsulfuration pathway being dysregulated.

Plasma Metabolomic Profiles in Recovered COVID-19 Patients without Previous Underlying Diseases 3 Months After Discharge

BACKGROUND

It remains unclear whether discharged COVID-19 patients have fully recovered from severe complications, including the differences in the post-infection metabolomic profiles of patients with different disease severities.

METHODS

COVID-19-recovered patients, who had no previous underlying diseases and were discharged from Wuhan Union Hospital for 3 months, and matched healthy controls (HCs) were recruited in this prospective cohort study. We examined the blood biochemical indicators, cytokines, lung computed tomography scans, including 39 HCs, 18 recovered asymptomatic (RAs), 34 recovered moderate (RMs), and 44 recovered severe/ critical patients (RCs). A liquid chromatography-mass spectrometry-based metabolomics approach was employed to profile the global metabolites of fasting plasma of these participants.

RESULTS

Clinical data and metabolomic profiles suggested that RAs recovered well, but some clinical indicators and plasma metabolites in RMs and RCs were still abnormal as compared with HCs, such as decreased taurine, succinic acid, hippuric acid, some indoles, and lipid species. The disturbed metabolic pathway mainly involved the tricarboxylic cycle, purine, and glycerophospholipid metabolism. Moreover, metabolite alterations differ between RMs and RCs when compared with HCs. Correlation analysis revealed that many differential metabolites were closely associated with inflammation and the renal, pulmonary, heart, hepatic, and coagulation system functions.

CONCLUSION

We uncovered metabolite clusters pathologically relevant to the recovery state in discharged COVID-19 patients which may provide new insights into the pathogenesis of potential organ damage in recovered patients.

Endogenous Taurine Downregulation Is Required for Renal Injury in Salt-Sensitive Hypertensive Rats via CBS/H2S Inhibition

Although taurine is known to exert an antihypertensive effect, it is unclear whether it is involved in the mechanism for hypertension-related target organ injury. To reveal the role of endogenous taurine in renal injury formation during salt-sensitive hypertension and clarify its mechanisms, both salt-sensitive Dahl rats and salt-resistant SS-13BN rats were fed a high-salt diet (8% NaCl) and given 2% taurine for 6 weeks. Rat systolic blood pressure (SBP) was measured by the tail-cuff method and artery catheterization. Kidney ultrastructure was observed under an electron microscope. Taurine content and mRNA and protein levels of taurine synthases, cysteine dioxygenase type 1 (CDO1) and cysteine sulfinic acid decarboxylase (CSAD), were decreased in Dahl rats fed a high-salt diet. However, taurine supplementation and the resulting increase in renal taurine content reduced the increased SBP and improved renal function and structural damage in high-salt diet-fed Dahl rats. In contrast, taurine did not affect SS-13BN SBP and renal function and structure. Taurine intervention increased the renal H₂S content and enhanced cystathionine-β-synthase (CBS) expression and activity in Dahl rats fed a high-salt diet. Taurine reduced the renin, angiotensin II, and aldosterone contents and the levels of oxidative stress indices in Dahl rat renal tissues but increased antioxidant capacity, antioxidant enzyme activity, and protein expression. However, taurine failed to achieve this effect in the renal tissue of SS-13BN rats fed a high-salt diet. Pretreatment with the CBS inhibitor HA or renal CBS knockdown inhibited H₂S generation and subsequently blocked the effect of taurine on renin, superoxide dismutase 1 (SOD1), and superoxide dismutase 2 (SOD2) levels in high-salt-stimulated Dahl renal slices. In conclusion, the downregulation of endogenous taurine production resulted in a decrease in the renal CBS/H₂S pathway. This decrease subsequently promoted renin-angiotensin-aldosterone system (RAAS) activation and oxidative stress in the kidney, ultimately contributing to renal injury in salt-sensitive Dahl rats.

H2S as a Bridge Linking Inflammation, Oxidative Stress and Endothelial Biology: A Possible Defense in the Fight against SARS-CoV-2 Infection?

The endothelium controls vascular homeostasis through a delicate balance between secretion of vasodilators and vasoconstrictors. The loss of physiological homeostasis leads to endothelial dysfunction, for which inflammatory events represent critical determinants. In this context, therapeutic approaches targeting inflammation-related vascular injury may help for the treatment of cardiovascular disease and a multitude of other conditions related to endothelium dysfunction, including COVID-19. In recent years, within the complexity of the inflammatory scenario related to loss of vessel integrity, hydrogen sulfide (H₂S) has aroused great interest due to its importance in different signaling pathways at the endothelial level. In this review, we discuss the effects of H₂S, a molecule which has been reported to demonstrate anti-inflammatory activity, in addition to many other biological functions related to endothelium and sulfur-drugs as new possible therapeutic options in diseases involving vascular pathobiology, such as in SARS-CoV-2 infection.

The Role of Taurine in Mitochondria Health: More Than Just an Antioxidant

Taurine is a naturally occurring sulfur-containing amino acid that is found abundantly in excitatory tissues, such as the heart, brain, retina and skeletal muscles. Taurine was first isolated in the 1800s, but not much was known about this molecule until the 1990s. In 1985, taurine was first approved as the treatment among heart failure patients in Japan. Accumulating studies have shown that taurine supplementation also protects against pathologies associated with mitochondrial defects, such as aging, mitochondrial diseases, metabolic syndrome, cancer, cardiovascular diseases and neurological disorders. In this review, we will provide a general overview on the mitochondria biology and the consequence of mitochondrial defects in pathologies. Then, we will discuss the antioxidant action of taurine, particularly in relation to the maintenance of mitochondria function. We will also describe several reported studies on the current use of taurine supplementation in several mitochondria-associated pathologies in humans.

Influence of innate immune activation on endocrine and metabolic pathways in infancy

Prematurity is the leading cause of neonatal morbidity and mortality worldwide. Premature infants often require extended hospital stays, with increased risk of developing infection compared with term infants. A picture is emerging of wide-ranging deleterious consequences resulting from innate immune system activation in the newborn infant. Those who survive infection have been exposed to a stimulus that can impose long-lasting alterations into later life. In this review, we discuss sepsis-driven alterations in integrated neuroendocrine and metabolic pathways and highlight current knowledge gaps in respect of neonatal sepsis. We review established biomarkers for sepsis and extend the discussion to examine emerging findings from human and animal models of neonatal sepsis that propose novel biomarkers for early identification of sepsis. Future research in this area is required to establish a greater understanding of the distinct neonatal signature of early and late-stage infection, to improve diagnosis, curtail inappropriate antibiotic use, and promote precision medicine through a biomarker-guided empirical and adjunctive treatment approach for neonatal sepsis. There is an unmet clinical need to decrease sepsis-induced morbidity in neonates, to limit and prevent adverse consequences in later life and decrease mortality.

Endothelial Progenitor Cells Dysfunctions and Cardiometabolic Disorders: From Mechanisms to Therapeutic Approaches

Metabolic syndrome (MetS) is a cluster of several disorders, such as hypertension, central obesity, dyslipidemia, hyperglycemia, insulin resistance and non-alcoholic fatty liver disease. Despite health policies based on the promotion of physical exercise, the reduction of calorie intake and the consumption of healthy food, there is still a global rise in the incidence and prevalence of MetS in the world. This phenomenon can partly be explained by the fact that adverse events in the perinatal period can increase the susceptibility to develop cardiometabolic diseases in adulthood. Individuals born after intrauterine growth restriction (IUGR) are particularly at risk of developing cardiovascular diseases (CVD) and metabolic disorders later in life. It has been shown that alterations in the structural and functional integrity of the endothelium can lead to the development of cardiometabolic diseases. The endothelial progenitor cells (EPCs) are circulating components of the endothelium playing a major role in vascular homeostasis. An association has been found between the maintenance of endothelial structure and function by EPCs and their ability to differentiate and repair damaged endothelial tissue. In this narrative review, we explore the alterations of EPCs observed in individuals with cardiometabolic disorders, describe some mechanisms related to such dysfunction and propose some therapeutical approaches to reverse the EPCs dysfunction.

The Effect of Dietary Supplements on Endurance Exercise Performance and Core Temperature in Hot Environments: A Meta-analysis and Meta-regression

BACKGROUND

The ergogenic effects of dietary supplements on endurance exercise performance are well-established; however, their efficacy in hot environmental conditions has not been systematically evaluated.

OBJECTIVES

(1) To meta-analyse studies investigating the effects of selected dietary supplements on endurance performance and core temperature responses in the heat. Supplements were included if they were deemed to: (a) have a strong evidence base for 'directly' improving thermoneutral endurance performance, based on current position statements, or (b) have a proposed mechanism of action that related to modifiable factors associated with thermal balance. (2) To conduct meta-regressions to evaluate the moderating effect of selected variables on endurance performance and core temperature responses in the heat following dietary supplementation.

METHODS

A search was performed using various databases in May 2020. After screening, 25 peer-reviewed articles were identified for inclusion, across three separate meta-analyses: (1) exercise performance; (2) end core temperature; (3) submaximal core temperature. The moderating effect of several variables were assessed via sub-analysis and meta-regression.

RESULTS

Overall, dietary supplementation had a trivial significant positive effect on exercise performance (Hedges' g = 0.18, 95% CI 0.007-0.352, P = 0.042), a trivial non-significant positive effect on submaximal core temperature (Hedges' g = 0.18, 95% CI - 0.021 to 0.379, P = 0.080) and a small non-significant positive effect on end core temperature (Hedges' g = 0.20, 95% CI - 0.041 to 0.439, P = 0.104) in the heat. There was a non-significant effect of individual supplements on exercise performance (P = 0.973) and submaximal core temperature (P = 0.599). However, end core temperature was significantly affected by supplement type (P = 0.003), which was attributable to caffeine's large significant positive effect (n = 8; Hedges' g = 0.82, 95% CI 0.433-1.202, P < 0.001) and taurine's medium significant negative effect (n = 1; Hedges' g = - 0.96, 95% CI - 1.855 to - 0.069, P = 0.035).

CONCLUSION

Supplements such as caffeine and nitrates do not enhance endurance performance in the heat, with caffeine also increasing core temperature responses. Some amino acids might offer the greatest performance benefits in the heat. Exercising in the heat negatively affected the efficacy of many dietary supplements, indicating that further research is needed and current guidelines for performance in hot environments likely require revision.

Review - Nutraceuticals Can Target Asthmatic Bronchoconstriction: NADPH Oxidase-Dependent Oxidative Stress, RhoA and Calcium Dynamics

Activation of various isoforms of NADPH oxidase contributes to the pathogenesis of asthma at multiple levels: promoting hypercontractility, hypertrophy, and proliferation of airway smooth muscle; enabling lung influx of eosinophils via VCAM-1; and mediating allergen-induced mast cell activation. Free bilirubin, which functions physiologically within cells as a feedback inhibitor of NADPH oxidase complexes, has been shown to have a favorable impact on each of these phases of asthma pathogenesis. The spirulina chromophore phycocyanobilin (PhyCB), a homolog of bilirubin’s precursor biliverdin, can mimic the inhibitory impact of biliverdin/bilirubin on NADPH oxidase activity, and spirulina’s versatile and profound anti-inflammatory activity in rodent studies suggests that PhyCB may have potential as a clinical inhibitor of NADPH oxidase. Hence, spirulina or PhyCB-enriched spirulina extracts merit clinical evaluation in asthma. Promoting biosynthesis of glutathione and increasing the expression and activity of various antioxidant enzymes – as by supplementing with N-acetylcysteine, Phase 2 inducers (eg, lipoic acid), selenium, and zinc – may also blunt the contribution of oxidative stress to asthma pathogenesis. Nitric oxide (NO) and hydrogen sulfide (H₂S) work in various ways to oppose pathogenic mechanisms in asthma; supplemental citrulline and high-dose folate may aid NO synthesis, high-dose biotin may mimic and possibly potentiate NO’s activating impact on soluble guanylate cyclase, and NAC and taurine may boost H₂S synthesis. The amino acid glycine has a hyperpolarizing effect on airway smooth muscle that is bronchodilatory. Insuring optimal intracellular levels of magnesium may modestly blunt the stimulatory impact of intracellular free calcium on bronchoconstriction. Nutraceutical regimens or functional foods incorporating at least several of these agents may have utility as nutraceutical adjuvants to standard clinical management of asthma.

Diet and Hydrogen Sulfide Production in Mammals

Significance: In recent times, it has emerged that some dietary sulfur compounds can act on mammalian cell signaling systems via their propensity to release hydrogen sulfide (H₂S). H₂S plays important biochemical and physiological roles in the heart, gastrointestinal tract, brain, kidney, and immune systems of mammals. Reduced levels of H₂S in cells and tissues correlate with a spectrum of pathophysiological conditions, including heart disease, diabetes, obesity, and altered immune function. Recent Advances: In the last decade, researchers have now begun to explore the mechanisms by which dietary-derived sulfur compounds, in addition to cysteine, can act as sources of H₂S. This research has led to the identified several compounds, organic sulfides, isothiocyanates, and inorganic sulfur species including sulfate that can act as potential sources of H₂S in mammalian cells and tissues. Critical Issues: We have summarised progress made in the identification of dietary factors that can impact on endogenous H₂S levels in mammals. We also describe current research focused on how some sulfur molecules present in dietary plants, and associated chemical analogues, act as sources of H₂S, and discuss the biological properties of these molecules as studied in a range of in vitro and in vivo systems. Future Directions: The identification of sulfur compounds in edible plants that can act as novel H₂S releasing molecules is intriguing. Research in this area could inform future studies exploring the impact of diet on H₂S levels in mammalian systems. Despite recent progress, additional work is needed to determine the mechanisms by which H₂S is released from these molecules following ingestions of dietary plants in humans, whether the amounts of H₂S produced is of physiological significance following the metabolism of these compounds in vivo, and if diet could be used to manipulated H₂S levels in humans. Importantly, this will lead to a better understanding of the biological significance of H₂S generated from dietary sources, and this information could be used in the development of plant breeding initiatives to increase the levels of H₂S releasing sulfur compounds in crops, or inform dietary intervention strategies that could be used to alter the levels of H₂S in humans.

Perioperative changes in the plasma metabolome of patients receiving general anesthesia for pancreatic cancer surgery

Background: Modern anesthesia strives to offer personalized concepts to meet the patient’s individual needs in sight of clinical outcome. Still, little is known about the impact of anesthesia on the plasma metabolome, although many metabolites have been shown to modulate the function of various immune cells, making it particularly interesting in the context of oncological surgery. In this study longitudinal dynamics in the plasma metabolome during general anesthesia in patients undergoing pancreatic surgery were analyzed.

Materials and Methods: Prospective, observational study with 10 patients diagnosed with pancreatic (pre-) malignancy and subjected to elective resection surgery under general anesthesia. Plasma metabolites (n = 630) were quantified at eight consecutive perioperative timepoints using mass spectrometry-based targeted metabolomics.

Results: 39 metabolites significantly changed during the perioperative period. Tryptophan concentrations decreased by 45% with the maximum decrease after anesthesia induction (p = 6.24E-07), while taurine synthesis increased (p = 1.46E-04). Triacylglycerides and lysophosphatidylcholines were significantly reduced with increased liberation of free monounsaturated fatty acids (p = 0.03). Carnitine levels decreased significantly (p = 9.30E-04).

Conclusions: The major finding of this study was perioperative tryptophan depletion and increased taurine synthesis. Both are essential for immune cell function and are therefore of significant interest for perioperative management. Further studies are needed to identify influencing anesthetic factors.

Ameliorative effect of taurine against diabetes and renal-associated disorders (Review)

To develop novel therapeutic methods for both diabetic and renal disorders, scientists had initially focused on elucidating the molecular mechanisms of taurine in established cell lines and mouse models. Although a large amount of data have been revealed, taurine has been confirmed to be the next step of novel promising therapeutic interventions against diabetic disorders. Taurine appears to ameliorate diabetes 1-related complications in various organs through its antioxidant, anti-inflammatory and anti-hormonal actions. In type 2 diabetes, taurine has been positively implicated in glucose homeostasis, exerting potent hypoglycemic, anti-obesity, hypotensive and hypolipidemic effects. Of particular interest is that taurine provides protection against renal dysfunction, including hypertension and proteinuria, specific glomerular and tubular disorders, acute and chronic renal conditions, and diabetic nephropathy. The ameliorative effects of taurine against renal disorders are based on its osmoregulatory properties, its association with signaling pathways and its association with the renin-angiotensin-aldosterone system (RAAS). Further clinical studies are required to ensure the importance of research findings.

Acute effects of energy drink on hemodynamic and electrophysiologic parameters in habitual and non-habitual caffeine consumers

BACKGROUND & AIMS

The consumption of energy drinks has significantly increased in recent years but their adverse effects are yet to be identified. The objective of the study is to determine the acute effects of energy drink on habitual and non-habitual caffeine consumers and if caffeine consumption habit causes a difference in the hemodynamic and electrophysiological responses.

METHODS

We carried out a non-randomized, non-placebo controlled, three-arm parallel assignment with 48 students enrolled at Aydın Adnan Menderes University. Four main groups were determined according to the results of the application acceptance survey. Blood pressure, electrocardiogram, breath rate, haemoglobin oxygen saturation and bioelectrical impedance analysis were measured before consuming the drinks. After consuming the drinks, measurements were repeated at 30 min and 60 min. In addition, Participant's Situation Anxiety Scale was recorded.

RESULTS

Energy drink consumption led to a significant increase in systolic blood pressure, diastolic blood pressure and heart rate for non-habitual caffeine consumers. PR interval and QRS complex were not affected significantly, however QTc interval reduced in time. Haemoglobin oxygen saturation and breathing rate did not change. Body fat percentage values of habitual energy drink consumers were smaller than the other groups. Body metabolism rate increased after energy drink consumption. There was no significant change for high-habitual caffeine consumers in all parameters evaluated.

CONCLUSIONS

Energy drink consumption has a negative effect on hemodynamic parameters. But as the habituation level increases the impact of energy drink on hemodynamic parameters tends to decrease.

CLINICALTRIALS REGISTRATION

Registered under ClinicalTrials.gov Identifier No: NCT04223167.

Microbiota and Metabolites as Factors Influencing Blood Pressure Regulation

The study of microbes has rapidly expanded in recent years due to a surge in our understanding that humans host a plethora of commensal microbes, which reside in their bodies and depending upon their composition, contribute to either normal physiology or pathophysiology. This article provides a general foundation for learning about host-commensal microbial interactions as an emerging area of research. The article is divided into two sections. The first section is dedicated to introducing commensal microbiota and its known effects on the host. The second section is on metabolites, which are biochemicals that the host and the microbes use for bi-directional communication with each other. Together, the sections review what is known about how microbes interact with the host to impact cardiovascular physiology, especially blood pressure regulation. © 2021 American Physiological Society. Compr Physiol 11:1731-1757, 2021.

Nutraceutical, Dietary, and Lifestyle Options for Prevention and Treatment of Ventricular Hypertrophy and Heart Failure

Although well documented drug therapies are available for the management of ventricular hypertrophy (VH) and heart failure (HF), most patients nonetheless experience a downhill course, and further therapeutic measures are needed. Nutraceutical, dietary, and lifestyle measures may have particular merit in this regard, as they are currently available, relatively safe and inexpensive, and can lend themselves to primary prevention as well. A consideration of the pathogenic mechanisms underlying the VH/HF syndrome suggests that measures which control oxidative and endoplasmic reticulum (ER) stress, that support effective nitric oxide and hydrogen sulfide bioactivity, that prevent a reduction in cardiomyocyte pH, and that boost the production of protective hormones, such as fibroblast growth factor 21 (FGF21), while suppressing fibroblast growth factor 23 (FGF23) and marinobufagenin, may have utility for preventing and controlling this syndrome. Agents considered in this essay include phycocyanobilin, N-acetylcysteine, lipoic acid, ferulic acid, zinc, selenium, ubiquinol, astaxanthin, melatonin, tauroursodeoxycholic acid, berberine, citrulline, high-dose folate, cocoa flavanols, hawthorn extract, dietary nitrate, high-dose biotin, soy isoflavones, taurine, carnitine, magnesium orotate, EPA-rich fish oil, glycine, and copper. The potential advantages of whole-food plant-based diets, moderation in salt intake, avoidance of phosphate additives, and regular exercise training and sauna sessions are also discussed. There should be considerable scope for the development of functional foods and supplements which make it more convenient and affordable for patients to consume complementary combinations of the agents discussed here. Research Strategy: Key word searching of PubMed was employed to locate the research papers whose findings are cited in this essay.

Nutraceuticals and blood pressure control: a European Society of Hypertension position document

: High-normal blood pressure (BP) is associated with an increased risk of cardiovascular disease, however the cost-benefit ratio of the use of antihypertensive treatment in these patients is not yet clear. Some dietary components and natural products seems to be able to significantly lower BP without significant side effects. The aim of this position document is to highlight which of these products have the most clinically significant antihypertensive action and wheter they could be suggested to patients with high-normal BP. Among foods, beetroot juice has the most covincing evidence of antihypertensive effect. Antioxidant-rich beverages (teas, coffee) could be considered. Among nutrients, magnesium, potassium and vitamin C supplements could improve BP. Among nonnutrient-nutraceuticals, soy isoflavones could be suggested in perimenopausal women, resveratrol in insulin-resistant patients, melatonin in study participants with night hypertension. In any case, the nutracutical approach has never to substitute the drug treatment, when needed.

Endothelium as a Source and Target of H2S to Improve Its Trophism and Function

The vascular endothelium consists of a single layer of squamous endothelial cells (ECs) lining the inner surface of blood vessels. Nowadays, it is no longer considered as a simple barrier between the blood and vessel wall, but a central hub to control blood flow homeostasis and fulfill tissue metabolic demands by furnishing oxygen and nutrients. The endothelium regulates the proper functioning of vessels and microcirculation, in terms of tone control, blood fluidity, and fine tuning of inflammatory and redox reactions within the vessel wall and in surrounding tissues. This multiplicity of effects is due to the ability of ECs to produce, process, and release key modulators. Among these, gasotransmitters such as nitric oxide (NO) and hydrogen sulfide (H₂S) are very active molecules constitutively produced by endotheliocytes for the maintenance and control of vascular physiological functions, while their impairment is responsible for endothelial dysfunction and cardiovascular disorders such as hypertension, atherosclerosis, and impaired wound healing and vascularization due to diabetes, infections, and ischemia. Upregulation of H₂S producing enzymes and administration of H₂S donors can be considered as innovative therapeutic approaches to improve EC biology and function, to revert endothelial dysfunction or to prevent cardiovascular disease progression. This review will focus on the beneficial autocrine/paracrine properties of H₂S on ECs and the state of the art on H₂S potentiating drugs and tools.

Type 2 diabetes preventive effects with a 12-months sardine-enriched diet in elderly population with prediabetes: An interventional, randomized and controlled trial

BACKGROUND

Fish could play a role in preventing type 2 diabetes (T2D) but there has been little specification about the type of fish and the preventive mechanism involved in its health claim. The sardine is a source of omega-3 and taurine that, in isolation or in synergy, would produce T2D-delaying through different molecular mechanism.

HYPOTHESIS

The consumption of twice a week of sardine, during one year would reduce T2D-developing risk in a population with prediabetes (preDM) and old age.

DESIGN

152 subjects with fasting glucose between 100-124 mg/dL aged ≥65 yo were recruited from three primary care centers in Barcelona and were randomly distributed among two interventional groups: control group (CG) and sardine group (SG). Both groups received same T2D-prevention nutritional during a year but only SG had to add 200 g of sardine per week. All variables were collected before to start and at the end of the diet. (ClinicalTrials.gov: NCT03557541).

RESULTS

152 people were randomized into CG (n=77) and SG (n=75) with 18 and 12 drop outs respectively. Subjects in SG, significantly compared to CG, decreased percentage classified-individuals in a very high risk group to develop T2D according to FINDRISC (p=0.035). In addition to increasing HDL-cholesterol and adiponectin and decreasing triglycerides (p<0.05) and blood pressure (<0.05), SG showed a lower HOMA-IR (p=0.032). The consumption of sardine characteristics nutrients as omega-3, EPA and DHA, vitamin D, fluorine and taurine were higher for SG (p<0.05). These results agreed with the increased of taurine, fatty acid (FA) omega-3 and bile acids circulating metabolites (p<0.05). Changes erythrocyte membrane FA were detected only in SG with a decrease of 5 omega-6 FA (p<0.001) and an increase of 3 omega-3 FA types (p<0.001).

CONCLUSION

We conclude that a year T2D-prevention diet with sardine supplementation has a greater protective effect against developing T2D and CV events.

Non-alcoholic fatty liver disease in adults: clinic, diagnostics, treatment. Guidelines for therapists, third version

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Osteoporosis and the effect of dysregulation of the transsulfuration pathway via taurine on intracellular calcium homeostasis, vitamin D absorption and vitamin K absorption

BACKGROUND & AIMS

In this article we connect the dysregulation of the transsulfuration pathway to bone dysregulations and propose a novel treatment for osteoporosis. Current treatments for osteoporosis are very frequently inadequate. In osteoporosis, the risk of fractures increases with increased homocysteine (Hcy).

METHODS

Here, we conduct a review on the relationship between osteoporosis and the dysregulation of the transsulfuration pathway.

RESULTS

we show that the transsulfuration pathway metabolizes Hcy to L-cysteine. Increased Hcy levels point to the transsulfuration pathway being dysregulated. With the transsulfuration pathway dysregulated, there will be decreased levels of L-cysteine and decreased levels of taurine, which is synthesized from L-cysteine. Taurine levels are decreased in patients with osteoporosis. Taurine regulates intracellular calcium homeostasis. Taurine, also, when conjugated with bile acids assists with absorption of fats and fat-soluble vitamins such as vitamin D and vitamin K. Dysregulated calcium homeostasis, decreased calcium absorption and decreased absorption of vitamin D and vitamin K due to low levels of taurine negatively affect bone mineral density (BMD) leading to osteoporosis and fractures.

CONCLUSIONS

In this article, we propose that a combination of taurine, calcium, vitamin D and vitamin K, could increase BMD reducing number of years spent in disability and reducing deaths due to fractures in patients with osteoporosis.

Taurine treatment reverses protein malnutrition-induced endothelial dysfunction of the pancreatic vasculature: The role of hydrogen sulfide

BACKGROUND

Protein malnutrition in childhood predisposes individuals to vascular and pancreatic endocrine dysfunction, thus increasing the risk of diabetes and hypertension. Because taurine may reduce cardiometabolic risk, we hypothesized that taurine treatment has a beneficial effect on the pancreatic vasculature during protein restriction.

METHODS AND RESULTS

Weaned mice were fed a normal or a low-protein diet and were treated with or without taurine for 3 months. The lieno-pancreatic artery (LPA) from low-protein diet-treated mice exhibited impaired endothelium-dependent relaxation to acetylcholine that was associated with decreased endothelium-derived hyperpolarization (EDH), hydrogen sulfide (H₂S) production, and H₂S-synthesizing CBS expression and impaired vasorelaxation to an H₂S-donor, NaHS. These changes were prevented by taurine treatment. We compared the effects of taurine with the effects of the direct vasodilator hydralazine and found that both normalized blood pressure and the endothelial vasodilator function of the LPA in the mice fed a protein-restricted diet. However, only taurine restored the CBS expression in the LPA and insulin secretion in response to high glucose. The LPA supplies the pancreas and shares morphometry with the mesenteric resistance artery (MRA). However, in the MRA, low-protein diet-induced endothelial dysfunction is driven by impaired NOS-derived NO with no changes in H₂S signaling.

CONCLUSIONS

The results suggest that taurine protects against protein malnutrition-induced endothelial dysfunction in the LPA by upregulating the CBS-H₂S pathway. Considering the importance of the pancreatic vasculature for endocrine islet activity, taurine may be a potential therapy for the vascular and metabolic dysfunction associated with malnutrition and comorbidities.

A Fundamental Role for Oxidants and Intracellular Calcium Signals in Alzheimer's Pathogenesis-And How a Comprehensive Antioxidant Strategy May Aid Prevention of This Disorder

Oxidative stress and increased cytoplasmic calcium are key mediators of the detrimental effects on neuronal function and survival in Alzheimer's disease (AD). Pathways whereby these perturbations arise, and then prevent dendritic spine formation, promote tau hyperphosphorylation, further amplify amyloid β generation, and induce neuronal apoptosis, are described. A comprehensive program of nutraceutical supplementation, comprised of the NADPH oxidase inhibitor phycocyanobilin, phase two inducers, the mitochondrial antioxidant astaxanthin, and the glutathione precursor N-acetylcysteine, may have important potential for antagonizing the toxic effects of amyloid β on neurons and thereby aiding prevention of AD. Moreover, nutraceutical antioxidant strategies may oppose the adverse impact of amyloid β oligomers on astrocyte clearance of glutamate, and on the ability of brain capillaries to export amyloid β monomers/oligomers from the brain. Antioxidants, docosahexaenoic acid (DHA), and vitamin D, have potential for suppressing microglial production of interleukin-1β, which potentiates the neurotoxicity of amyloid β. Epidemiology suggests that a health-promoting lifestyle, incorporating a prudent diet, regular vigorous exercise, and other feasible measures, can cut the high risk for AD among the elderly by up to 60%. Conceivably, complementing such lifestyle measures with long-term adherence to the sort of nutraceutical regimen outlined here may drive down risk for AD even further.

Renal metabolism and hypertension

Hypertension is a leading risk factor for disease burden worldwide. The kidneys, which have a high specific metabolic rate, play an essential role in the long-term regulation of arterial blood pressure. In this review, we discuss the emerging role of renal metabolism in the development of hypertension. Renal energy and substrate metabolism is characterized by several important and, in some cases, unique features. Recent advances suggest that alterations of renal metabolism may result from genetic abnormalities or serve initially as a physiological response to environmental stressors to support tubular transport, which may ultimately affect regulatory pathways and lead to unfavorable cellular and pathophysiological consequences that contribute to the development of hypertension.

Protective effect of oral histidine on hypertension in Dahl salt-sensitive rats induced by high-salt diet

AIMS

Salt-sensitive hypertension is a risk factor for cardiovascular disease. Previous studies have shown that insufficient arginine in the kidney caused by metabolic imbalance is an important factor in salt-sensitive hypertension. Whether the high nitrogen content of histidine can affect the balance of nitrogen metabolism in Dahl salt-sensitive (SS) rats. This article aimed to study the effects of oral histidine on salt-sensitive hypertension, kidney damage and metabolic patterns of high-salt diet in SS rats.

MAIN METHODS

Adult rats were divided into four groups, and blood pressure was measured using a non-invasive tail-cuff system. Gas chromatography-mass spectrometry analyzed metabolites in serum and kidney tissues.

KEY FINDINGS

High-salt diet significantly increased the blood pressure of rats and aggravated kidney damage. Of note, histidine can attenuate salt-sensitive hypertension and kidney damage by improving metabolic pattern, reducing Reactive Oxygen Species (ROS) and increasing nitric oxide levels in SS rats.

SIGNIFICANCE

These results suggest that histidine could be a potential adjuvant to prevent and control salt-sensitive hypertension.

Physiological and thermoregulatory effects of oral taurine supplementation on exercise tolerance during forced convective cooling

AbstractWe investigated the effects of taurine supplementation on cycling time to exhaustion in cold conditions. Eleven males cycled to exhaustion at a power output equivalent to the mid-point between ventilatory threshold and maximum aerobic power following 15-min rest in the cold (apparent temperature of ∼ 4°C; air flow of 4.17 m s^-1). Two hours before, participants ingested taurine (50 mg·kg^-1) or placebo beverage. Pulmonary gases, carbohydrate (CHO) and fat oxidation, body temperatures, mean local sweat rate, heart rate, rate of perceived exertion (RPE) and thermal comfort were recorded. Time to exhaustion was not different between trials (taurine = 14.6 ± 4.7 min; placebo = 13.4 ± 5.6 min, P = 0.061, d = 0.27). There were no effects (P > 0.05) of taurine on core temperature, mean skin temperature or local sweat rates. However, the placebo condition showed greater (P < 0.05) reductions in arm-to-finger temperature gradient (i.e. vasodilation) across pre-exercise passive cold exposure and increased CHO oxidation (P < 0.05). Participants also reached a thermally 'comfortable' level quicker in the taurine condition (P < 0.05). A 50 mg·kg^-1 dose of taurine did not statistically benefit endurance exercise after moderate cold exposure but conferred some potential vascular and metabolic effects.Highlights In the first study to examine the effects of acute taurine supplementation on exercise performance in cold conditions, we found no significant effects on exercise performance, despite the small effect size.We found preliminary evidence of effects on metabolism during exercise, with taurine supplementation moderately reducing whole-body CHO oxidation rate.Supplementation of taurine also conferred possible skin vascular effects, which was indicative of less vasodilation (or greater sustained vascular tone) when presented with a cold environmental stimulus.Future research should extend these findings to prolonged exercise at colder body temperatures, where the small effects revealed here could have greater influence on human performance and cold tolerability.

Nutraceutical Strategies for Suppressing NLRP3 Inflammasome Activation: Pertinence to the Management of COVID-19 and Beyond

Inflammasomes are intracellular protein complexes that form in response to a variety of stress signals and that serve to catalyze the proteolytic conversion of pro-interleukin-1β and pro-interleukin-18 to active interleukin-1β and interleukin-18, central mediators of the inflammatory response; inflammasomes can also promote a type of cell death known as pyroptosis. The NLRP3 inflammasome has received the most study and plays an important pathogenic role in a vast range of pathologies associated with inflammation-including atherosclerosis, myocardial infarction, the complications of diabetes, neurological and autoimmune disorders, dry macular degeneration, gout, and the cytokine storm phase of COVID-19. A consideration of the molecular biology underlying inflammasome priming and activation enables the prediction that a range of nutraceuticals may have clinical potential for suppressing inflammasome activity-antioxidants including phycocyanobilin, phase 2 inducers, melatonin, and N-acetylcysteine, the AMPK activator berberine, glucosamine, zinc, and various nutraceuticals that support generation of hydrogen sulfide. Complex nutraceuticals or functional foods featuring a number of these agents may find utility in the prevention and control of a wide range of medical disorders.

Comprehensive Metabolic Phenotyping Refines Cardiovascular Risk in Young Adults

BACKGROUND

Whereas cardiovascular disease (CVD) metrics define risk in individuals >40 years of age, the earliest lesions of CVD appear well before this age. Despite the role of metabolism in CVD antecedents, studies in younger, biracial populations to define precise metabolic risk phenotypes are lacking.

METHODS

We studied 2330 White and Black young adults (mean age, 32 years; 45% Black) in the CARDIA study (Coronary Artery Risk Development in Young Adults) to identify metabolite profiles associated with an adverse CVD phenome (myocardial structure/function, fitness, vascular calcification), mechanisms, and outcomes over 2 decades. Statistical learning methods (elastic nets/principal components analysis) and Cox regression generated parsimonious, metabolite-based risk scores validated in >1800 individuals in the Framingham Heart Study.

RESULTS

In the CARDIA study, metabolite profiles quantified in early adulthood were associated with subclinical CVD development over 20 years, specifying known and novel pathways of CVD (eg, transcriptional regulation, brain-derived neurotrophic factor, nitric oxide, renin-angiotensin). We found 2 multiparametric, metabolite-based scores linked independently to vascular and myocardial health, with metabolites included in each score specifying microbial metabolism, hepatic steatosis, oxidative stress, nitric oxide modulation, and collagen metabolism. The metabolite-based vascular scores were lower in men, and myocardial scores were lower in Black participants. Over a nearly 25-year median follow-up in CARDIA, the metabolite-based vascular score (hazard ratio, 0.68 per SD [95% CI, 0.50-0.92]; P=0.01) and myocardial score (hazard ratio, 0.60 per SD [95% CI, 0.45-0.80]; P=0.0005) in the third and fourth decades of life were associated with clinical CVD with a synergistic association with outcome (Pinteraction=0.009). We replicated these findings in 1898 individuals in the Framingham Heart Study over 2 decades, with a similar association with outcome (including interaction), reclassification, and discrimination. In the Framingham Heart Study, the metabolite scores exhibited an age interaction (P=0.0004 for a combined myocardial-vascular score with incident CVD), such that young adults with poorer metabolite-based health scores had highest hazard of future CVD.

CONCLUSIONS

Metabolic signatures of myocardial and vascular health in young adulthood specify known/novel pathways of metabolic dysfunction relevant to CVD, associated with outcome in 2 independent cohorts. Efforts to include precision measures of metabolic health in risk stratification to interrupt CVD at its earliest stage are warranted.

Metabolic Architecture of Acute Exercise Response in Middle-Aged Adults in the Community

BACKGROUND

Whereas regular exercise is associated with lower risk of cardiovascular disease and mortality, mechanisms of exercise-mediated health benefits remain less clear. We used metabolite profiling before and after acute exercise to delineate the metabolic architecture of exercise response patterns in humans.

METHODS

Cardiopulmonary exercise testing and metabolite profiling was performed on Framingham Heart Study participants (age 53±8 years, 63% women) with blood drawn at rest (n=471) and at peak exercise (n=411).

RESULTS

We observed changes in circulating levels for 502 of 588 measured metabolites from rest to peak exercise (exercise duration 11.9±2.1 minutes) at a 5% false discovery rate. Changes included reductions in metabolites implicated in insulin resistance (glutamate, -29%; P=1.5×10-55; dimethylguanidino valeric acid [DMGV], -18%; P=5.8×10-18) and increases in metabolites associated with lipolysis (1-methylnicotinamide, +33%; P=6.1×10-67), nitric oxide bioavailability (arginine/ornithine + citrulline, +29%; P=2.8×10-169), and adipose browning (12,13-dihydroxy-9Z-octadecenoic acid +26%; P=7.4×10-38), among other pathways relevant to cardiometabolic risk. We assayed 177 metabolites in a separate Framingham Heart Study replication sample (n=783, age 54±8 years, 51% women) and observed concordant changes in 164 metabolites (92.6%) at 5% false discovery rate. Exercise-induced metabolite changes were variably related to the amount of exercise performed (peak workload), sex, and body mass index. There was attenuation of favorable excursions in some metabolites in individuals with higher body mass index and greater excursions in select cardioprotective metabolites in women despite less exercise performed. Distinct preexercise metabolite levels were associated with different physiologic dimensions of fitness (eg, ventilatory efficiency, exercise blood pressure, peak Vo2). We identified 4 metabolite signatures of exercise response patterns that were then analyzed in a separate cohort (Framingham Offspring Study; n=2045, age 55±10 years, 51% women), 2 of which were associated with overall mortality over median follow-up of 23.1 years (P≤0.003 for both).

CONCLUSIONS

In a large sample of community-dwelling individuals, acute exercise elicits widespread changes in the circulating metabolome. Metabolic changes identify pathways central to cardiometabolic health, cardiovascular disease, and long-term outcome. These findings provide a detailed map of the metabolic response to acute exercise in humans and identify potential mechanisms responsible for the beneficial cardiometabolic effects of exercise for future study.

The role of host defences in Covid 19 and treatments thereof

Hydrogen sulfide (H₂S) is a natural defence against the infections from enveloped RNA viruses and is likely involved also in Covid 19. It was already shown to inhibit growth and pathogenic mechanisms of a variety of enveloped RNA viruses and it was now found that circulating H₂S is higher in Covid 19 survivors compared to fatal cases. H₂S release is triggered by carbon monoxide (CO) from the catabolism of heme by inducible heme oxygenase (HO-1) and heme proteins possess catalytic activity necessary for the H₂S signalling by protein persulfidation. Subjects with a long promoter for the HMOX1 gene, coding for HO-1, are predicted for lower efficiency of this mechanism. SARS-cov-2 exerts ability to attack the heme of hemoglobin and other heme-proteins thus hampering both release and signalling of H₂S. Lack of H₂S-induced persulfidation of the K_ATP channels of leucocytes causes adhesion and release of the inflammatory cytokines, lung infiltration and systemic endothelial damage with hyper-coagulability. These events largely explain the sex and age distribution, clinical manifestations and co-morbidities of Covid-19. The understanding of this mechanism may be of guidance in re-evaluating the ongoing therapeutic strategies, with special attention to the interaction with mechanical ventilation, paracetamol and chloroquine use, and in the individuation of genetic traits causing increased susceptibility to the disruption of these physiologic processes and to a critical Covid 19. Finally, an array of therapeutic interventions with the potential to clinically modulate the HO-1/CO/H₂S axis is already available or under development. These include CO donors and H₂S donors and a boost to the endogenous production of H₂S is also possible.

Atherosclerosis Linked to Aberrant Amino Acid Metabolism and Immunosuppressive Amino Acid Catabolizing Enzymes

Cardiovascular disease is the leading global health concern and responsible for more deaths worldwide than any other type of disorder. Atherosclerosis is a chronic inflammatory disease in the arterial wall, which underpins several types of cardiovascular disease. It has emerged that a strong relationship exists between alterations in amino acid (AA) metabolism and the development of atherosclerosis. Recent studies have reported positive correlations between levels of branched-chain amino acids (BCAAs) such as leucine, valine, and isoleucine in plasma and the occurrence of metabolic disturbances. Elevated serum levels of BCAAs indicate a high cardiometabolic risk. Thus, BCAAs may also impact atherosclerosis prevention and offer a novel therapeutic strategy for specific individuals at risk of coronary events. The metabolism of AAs, such as L-arginine, homoarginine, and L-tryptophan, is recognized as a critical regulator of vascular homeostasis. Dietary intake of homoarginine, taurine, and glycine can improve atherosclerosis by endothelium remodeling. Available data also suggest that the regulation of AA metabolism by indoleamine 2,3-dioxygenase (IDO) and arginases 1 and 2 are mediated through various immunological signals and that immunosuppressive AA metabolizing enzymes are promising therapeutic targets against atherosclerosis. Further clinical studies and basic studies that make use of animal models are required. Here we review recent data examining links between AA metabolism and the development of atherosclerosis.

The Anti-Inflammatory Effect of Taurine on Cardiovascular Disease

Taurine is a non-protein amino acid that is expressed in the majority of animal tissues. With its unique sulfonic acid makeup, taurine influences cellular functions, including osmoregulation, antioxidation, ion movement modulation, and conjugation of bile acids. Taurine exerts anti-inflammatory effects that improve diabetes and has shown benefits to the cardiovascular system, possibly by inhibition of the renin angiotensin system. The beneficial effects of taurine are reviewed.

Taurine mitigates cirrhosis-associated heart injury through mitochondrial-dependent and antioxidative mechanisms

Cirrhosis-induced heart injury and cardiomyopathy is a serious consequence of this disease. It has been shown that bile duct ligated (BDL) animals could serve as an appropriate experimental model to investigate heart tissue injury in cirrhosis. The accumulation of cytotoxic chemicals (e.g., bile acids) could also adversely affect the heart tissue. Oxidative stress and mitochondrial impairment are the most prominent mechanisms of bile acid cytotoxicity. Taurine (Tau) is the most abundant non-protein amino acid in the human body. The cardioprotective effects of this amino acid have repeatedly been investigated. In the current study, it was examined whether mitochondrial dysfunction and oxidative stress are involved in the pathogenesis of cirrhosis-induced heart injury. Rats underwent BDL surgery. BDL animals received Tau (50, 100, and 500 mg/kg, i.p.) for 42 consecutive days. A significant increase in oxidative stress biomarkers was detected in the heart tissue of BDL animals. Moreover, it was found that heart tissue mitochondrial indices of functionality were deteriorated in the BDL group. Tau treatment significantly decreased oxidative stress and improved mitochondrial function in the heart tissue of cirrhotic animals. These data provide clues for the involvement of mitochondrial impairment and oxidative stress in the pathogenesis of heart injury in BDL rats. On the other hand, Tau supplementation could serve as an effective ancillary treatment against BDL-associated heart injury. Mitochondrial regulating and antioxidative properties of Tau might play a fundamental role in its mechanism of protective effects in the heart tissue of BDL animals.

Associations between honey consumption and prehypertension in adults aged 40 years and older

Background: Honey has been shown to have multiple positive effects on human health. However, data on the associations of honey consumption with prehypertension are scarce. The aim of this study was to investigate whether honey consumption is associated with prehypertension in a Chinese population. Method: A cross-sectional study was conducted in 4,561 individuals aged ≥40 years. A validated 100-item semi-quantitative food frequency questionnaire was used to assess honey consumption. Blood pressure was measured at least twice by trained nurses. Multiple logistic regression models were used to explore the associations between honey consumption and prehypertension. Results: After adjustment for potential confounders, the odds ratios and 95% confidence intervals of prehypertension across increasing frequency of honey consumption were 1.00 (reference) for almost never, 1.17 (0.96, 1.41) for ≤6 times/week, and 1.25 (0.86, 1.84) for ≥7 times/week in men (P _{for trend} = 0.09); 1.00 (reference) for almost never, 0.76 (0.62, 0.92) for ≤6 times/week, and 0.84 (0.63, 1.12) for ≥7 times/week in women (P _{for trend} = 0.055), respectively. Conclusion: Our results showed that light-to-moderate intake of honey was associated with lower prevalence of prehypertension in women, but not men. Future studies are required to confirm these associations.

Qingda granules attenuate hypertensive cardiac remodeling and inflammation in spontaneously hypertensive rats

Qingda granules (QDG) are derived from QingXuanJiangYa Decoction (QXJYD) a traditional Chinese medication that has been used to treat hypertension for more than 60 years. QXJYD has been shown to be effective in rat models of hypertension. However, the effects of QDG on hypertension remain largely unknown. In the current study, baicalin was identified as one of the main components of QDG using Ultra Performance Liquid Chromatography (UPLC) analysis. We investigated the effects of QDG on blood pressure, cardiac remodeling, and cardiac inflammation. QDG (0.8 g/kg/day) treatment attenuated the elevated blood pressure in spontaneously hypertensive rats (SHRs). Moreover, QDG treatment reduced the degree of myocardial fiber disarray, degeneration and necrosis of myocardial cells, expression of ANP and BNP, as well as collagen content of SHRs. Moreover, we further assessed the effect of QDG treatment on cardiac inflammation and found that QDG treatment reduced CD68 protein expression, decreased levels of IL-6 and TNF-α in both serum and cardiac tissues, as well as suppressed activation of NF-κB pathway in cardiac tissues of SHRs. Differential expressed metabolites (DEMs) analysis identified 41 increased and 51 decreased metabolites in the cardiac tissues of SHRs after QDG treatment. In summary, QDG treatment of SHRs attenuated the elevated blood pressure and ameliorated cardiac remodeling and inflammation, in part, through suppression of NF-κB pathway and DEMs, which provide a basis for other therapeutic uses of this TCM.

Diurnal Timing Dependent Alterations in Gut Microbial Composition Are Synchronously Linked to Salt-Sensitive Hypertension and Renal Damage

Alterations of diurnal rhythms of blood pressure (BP) and reshaping of gut microbiota are both independently associated with hypertension. However, the relationships between biorhythms of BP and gut microbial composition are unknown. We hypothesized that diurnal timing-associated alterations of microbial compositions are synchronous with diurnal rhythmicity, dip in BP, and renal function. To test this hypothesis, Dahl salt-sensitive (S) rats on low- and high-salt diets were examined for time of day effects on gut microbiota, BP, and indicators of renal damage. Major shifts in night and day patterns of specific groups of microbiota were observed between the dark (active) and light (rest) phases, which correlated with diurnal rhythmicity of BP. The diurnal abundance of Firmicutes, Bacteroidetes, and Actinobacteria were independently associated with BP. Discrete bacterial taxa were observed to correlate independently or interactively with one or more of the following 3 factors: (1) BP rhythm, (2) dietary salt, and (3) dip in BP. Phylogenetic Investigation of Communities revealed diurnal timing effects on microbial pathways, characterized by upregulated biosynthetic processes during the active phase of host, and upregulated degradation pathways of metabolites in the resting phase. Additional metagenomics functional pathways with rhythm variations were noted for aromatic amino acid metabolism and taurine metabolism. These diurnal timing dependent changes in microbiota, their functional pathways, and BP dip were associated with concerted effects of the levels of renal lipocalin 2 and kidney injury molecule-1 expression. These data provide evidence for a firm and concerted diurnal timing effects of BP, renal damage, and select microbial communities.

Nutraceuticals Targeting Generation and Oxidant Activity of Peroxynitrite May Aid Prevention and Control of Parkinson's Disease

Parkinson's disease (PD) is a chronic low-grade inflammatory process in which activated microglia generate cytotoxic factors-most prominently peroxynitrite-which induce the death and dysfunction of neighboring dopaminergic neurons. Dying neurons then release damage-associated molecular pattern proteins such as high mobility group box 1 which act on microglia via a range of receptors to amplify microglial activation. Since peroxynitrite is a key mediator in this process, it is proposed that nutraceutical measures which either suppress microglial production of peroxynitrite, or which promote the scavenging of peroxynitrite-derived oxidants, should have value for the prevention and control of PD. Peroxynitrite production can be quelled by suppressing activation of microglial NADPH oxidase-the source of its precursor superoxide-or by down-regulating the signaling pathways that promote microglial expression of inducible nitric oxide synthase (iNOS). Phycocyanobilin of spirulina, ferulic acid, long-chain omega-3 fatty acids, good vitamin D status, promotion of hydrogen sulfide production with taurine and N-acetylcysteine, caffeine, epigallocatechin-gallate, butyrogenic dietary fiber, and probiotics may have potential for blunting microglial iNOS induction. Scavenging of peroxynitrite-derived radicals may be amplified with supplemental zinc or inosine. Astaxanthin has potential for protecting the mitochondrial respiratory chain from peroxynitrite and environmental mitochondrial toxins. Healthful programs of nutraceutical supplementation may prove to be useful and feasible in the primary prevention or slow progression of pre-existing PD. Since damage to the mitochondria in dopaminergic neurons by environmental toxins is suspected to play a role in triggering the self-sustaining inflammation that drives PD pathogenesis, there is also reason to suspect that plant-based diets of modest protein content, and possibly a corn-rich diet high in spermidine, might provide protection from PD by boosting protective mitophagy and thereby aiding efficient mitochondrial function. Low-protein diets can also promote a more even response to levodopa therapy.

The Effects of Taurine Supplementation on Metabolic Profiles, Pentosidine, Soluble Receptor of Advanced Glycation End Products and Methylglyoxal in Adults With Type 2 Diabetes: A Randomized, Double-Blind, Placebo-Controlled Trial

OBJECTIVES

Advanced glycation end products, along with methylglyoxal (MGO) as their precursor, play a major role in increased complications of type 2 diabetes mellitus (T2DM). Taurine (2-aminoethanesulphonic acid), a conditionally essential amino acid, is found in most mammalian tissues. Taurine is known as an antiglycation compound. This study was designed to investigate the effects of taurine supplementation on metabolic profiles, pentosidine, MGO and soluble receptors for advanced glycation end products in patients with T2DM.

METHODS

In this double-blind randomized controlled trial, 46 patients with T2DM were randomly allocated into taurine and placebo groups. Participants received either 3,000 mg/day taurine or placebo for 8 weeks. Metabolic profiles, pentosidine, MGO and soluble receptors for advanced glycation end products levels were assessed after 12 h of fasting at baseline and completion of the clinical trial. Independent t test, paired t test, Pearson correlation and analysis of covariance were used for analysis.

RESULTS

The mean serum levels of fasting blood sugar (p=0.01), glycated hemoglobin (p=0.04), insulin (p=0.03), homeostasis model assessment-insulin resistance (p=0.004), total cholesterol (p=0.01) and low-density lipoprotein cholesterol (p=0.03) significantly were reduced in the taurine group at completion compared with the placebo group. In addition, after completion of the study, pentosidine (p=0.004) and MGO (p=0.006) were significantly reduced in the taurine group compared with the placebo group.

CONCLUSIONS

The results of this trial show that taurine supplementation may decrease diabetes complications through improving glycemic control and advanced glycation end products.

A disease-modifying treatment for Alzheimer's disease: focus on the trans-sulfuration pathway

High homocysteine levels in Alzheimer's disease (AD) result from low activity of the trans-sulfuration pathway. Glutathione levels are also low in AD. L-cysteine is required for the synthesis of glutathione. The synthesis of coenzyme A (CoA) requires L-cysteine, which is synthesized via the trans-sulfuration pathway. CoA is required for the synthesis of acetylcholine and appropriate cholinergic neurotransmission. L-cysteine is required for the synthesis of molybdenum-containing proteins. Sulfite oxidase (SUOX), which is a molybdenum-containing protein, could be dysregulated in AD. SUOX detoxifies the sulfites. Glutaminergic neurotransmission could be dysregulated in AD due to low levels of SUOX and high levels of sulfites. L-cysteine provides sulfur for iron-sulfur clusters. Oxidative phosphorylation (OXPHOS) is heavily dependent on iron-sulfur proteins. The decrease in OXPHOS seen in AD could be due to dysregulations of the trans-sulfuration pathway. There is a decrease in aconitase 1 (ACO1) in AD. ACO1 is an iron-sulfur enzyme in the citric acid cycle that upon loss of an iron-sulfur cluster converts to iron regulatory protein 1 (IRP1). With the dysregulation of iron-sulfur cluster formation ACO1 will convert to IRP1 which will decrease the 2-oxglutarate synthesis dysregulating the citric acid cycle and also dysregulating iron metabolism. Selenomethionine is also metabolized by the trans-sulfuration pathway. With the low activity of the trans-sulfuration pathway in AD selenoproteins will be dysregulated in AD. Dysregulation of selenoproteins could lead to oxidant stress in AD. In this article, we propose a novel treatment for AD that addresses dysregulations resulting from low activity of the trans-sulfuration pathway and low L-cysteine.

Gut microbiota and neuroinflammation in pathogenesis of hypertension: A potential role for hydrogen sulfide

Inflammation and gut dysbiosis are hallmarks of hypertension (HTN). Hydrogen sulfide (H2S) is an important freely diffusing molecule that modulates the function of neural, cardiovascular and immune systems, and circulating levels of H2S are reduced in animals and humans with HTN. While most research to date has focused on H₂S produced endogenously by the host, H2S is also produced by the gut bacteria and may affect the host homeostasis. Here, we review an association between neuroinflammation and gut dysbiosis in HTN, with special emphasis on a potential role of H2S in this interplay.

Hydrogen Sulfide in Pharmacotherapy, Beyond the Hydrogen Sulfide-Donors

Hydrogen sulfide (H₂S) is one of the important biological mediators involved in physiological and pathological processes in mammals. Recently developed H₂S donors show promising effects against several pathological processes in preclinical and early clinical studies. For example, H₂S donors have been found to be effective in the prevention of gastrointestinal ulcers during anti-inflammatory treatment. Notably, there are well-established medicines used for the treatment of a variety of diseases, whose chemical structure contains sulfur moieties and may release H₂S. Hence, the therapeutic effect of these drugs may be partly the result of the release of H₂S occurring during drug metabolism and/or the effect of these drugs on the production of endogenous hydrogen sulfide. In this work, we review data regarding sulfur drugs commonly used in clinical practice that can support the hypothesis about H₂S-dependent pharmacotherapeutic effects of these drugs.

High-salt intake increases TRPC3 expression and enhances TRPC3-mediated calcium influx and systolic blood pressure in hypertensive patients

Enhanced transient receptor potential canonical subtype 3 (TRPC3) expression and TRPC3-mediated calcium influx in monocytes from hypertensive rats and patients are associated with increased blood pressure. Daily salt intake is closely related to hypertension, but the relationship between TRPC3 expression and salt intake has not yet been evaluated in hypertensive patients. Using reverse transcription-polymerase chain reaction, we studied the expression of TRPC3 and TRPC3-related store-operated calcium entry (SOCE) in peripheral blood mononuclear cells (PBMCs) from hypertensive and normotensive control subjects. Measurement of SOCE was performed using the fluorescent dye Fura-2 AM. Participants were divided into a low-salt group (<9 g) and a high-salt group (≥9 g) based on 24-h urinary sodium excretion. Increased TRPC3 mRNA expression levels and SOCE were observed in THP-1 cells after high-NaCl treatment. However, administration of the TRPC3-specific inhibitor Pyr3 significantly decreased the effect. Furthermore, the TRPC3 mRNA expression levels in PBMCs from high-salt intake patients with essential hypertension were significantly higher than those in low-salt intake patients compared with those in normotensive control subjects. We also observed significantly increased TRPC3-mediated SOCE in PBMCs from hypertensive subjects (but not from normotensive control subjects), with calcium concentration correlating with salt intake. More importantly, TRPC3 mRNA levels showed a significant correlation with salt intake and systolic blood pressure in patients with essential hypertension. This study demonstrated, for the first time, that increased TRPC3 mRNA levels are associated with elevated salt intake and systolic blood pressure in hypertensive patients.

Perinatal taurine exerts a hypotensive effect in male spontaneously hypertensive rats and down-regulates endothelial oxide nitric synthase in the aortic arch

Essential hypertension is considered to be a result of the interaction between genetic and environmental factors, including perinatal factors. Different advantageous perinatal factors proved to have beneficial long-lasting effects against an abnormal genetic background. Taurine is a ubiquitous sulphur-containing amino acid present in foods such as seafood. The antihypertensive effects of taurine have been reported in experimental studies and in human hypertension. We aimed to investigate the effects of perinatal treatment with taurine in spontaneously hypertensive rats (SHR), a known model of genetic hypertension. Female SHR were administered with taurine (3 g/L) during gestation and lactation (SHR-TAU). Untreated SHR and Wistar-Kyoto rats (WKY) were used as controls. Long-lasting effects in offspring were investigated. Addition of taurine to the mother's drinking water reduced blood pressure in adult offspring. No differences were observed in cardiac hypertrophy. Findings on morphometric evaluations suggest that perinatal treatment with taurine would be partially effective in improving structural alterations of the aorta. Modifications in gene expression of Bcl-2 family members and upregulation of endothelial nitric oxide synthase in the aorta of 22-week-old male offspring were found. No differences were observed on relative telomere length in different cardiovascular tissues between SHR and SHR-TAU. Altogether results suggest that taurine programming, albeit sex specific, is associated with gene expression changes which ultimately may lead to improvement of aortic remodelling and enhanced endothelial function because of augmented nitric oxide (NO) production.

Cardiovascular and Autonomic Responses to Energy Drinks-Clinical Implications

There is an increasing consumption of energy drinks both in the United States and worldwide. The components of these beverages are sometimes unclear but commonly include caffeine, sugars, taurine, and B-vitamins. Young people, particularly those engaged in sports, studying, and in the military are especially likely to be consumers of energy drinks. While limited data are available regarding their autonomic and hemodynamic effects, current literature suggests that energy drink consumption is accompanied by increases in blood pressure, sympathetic drive, and also in QT prolongation. There are no systematic long term studies identifying consequences of frequent energy drink consumption. However, multiple anecdotal reports implicate energy drinks in adverse cardiovascular events including atrial fibrillation, ventricular arrhythmia, myocardial infarction, and sudden death. Events such as atrial fibrillation may even occur in otherwise healthy subjects with structurally normal hearts. It is likely that these cardiovascular outcomes are triggered by the hemodynamic, autonomic, and electrocardiographic responses to energy drink consumption. What remains unclear is how concomitant use of other stimulants such as amphetamines and nicotine may interact to potentiate neural and circulatory responses and cardiovascular consequences when combined with energy drinks.

Genetic Susceptibility, Dietary Protein Intake, and Changes of Blood Pressure: The POUNDS Lost Trial

High blood pressure (BP) is closely related to obesity, and weight loss lowers BP. Evidence has shown considerable interpersonal variation of changes in BP among people experiencing weight loss, and such variation might be partly determined by genetic factors. We assessed the changes in systolic and diastolic BP (SBP/DBP) among 692 participants randomly assigned to 1 of 4 diets varying in macronutrient content for 2 years. Two separate polygenic scores (SBP/DBP-PGS derived from 52/50 single nucleotide polymorphisms) were built for each participant based on 66 BP-associated single nucleotide polymorphisms. During a 2-year intervention, participants in the bottom versus upper tertile of SBP/DBP-PGS had a greater decrease in SBP (△SBP at 6, 12, and 24 months: -3.84 versus -1.61, -4.76 versus -2.75, -2.49 versus -1.63; P=0.001) or in DBP (△DBP at 6, 12, and 24 months: -3.09 versus -1.34, -2.69 versus -1.44, -1.82 versus -0.53; P<0.001). We also found gene-diet interaction on changes in SBP from baseline to 24 months (Pinteraction=0.009). Among participants assigned to a high-protein diet, those with a lower SBP-polygenic scores had greater decreases in SBP at months 6 (P=0.018), months 12 (P=0.007), and months 24 (P=0.089); while no significant difference was observed across the SBP-polygenic scores tertile groups among those assigned to an average-protein diet (all P values >0.05). Our data indicate that genetic susceptibility may affect BP changes in response to weight-loss diet interventions, and protein intake may modify the genetic associations with changes in BP. This trial was registered at URL: http://www.clinicaltrials.gov. Unique identifier: NCT00072995.

Modulation of endothelium-derived nitric oxide production and activity by taurine and taurine-conjugated bile acids

Taurine is a semiessential amino acid found at high concentrations in mammalian plasma and cells, where it regulates cellular functions such as ion flux, controls cell volume and serves as a substrate for conjugated bile acids (BAs). Exogenous administration of both taurine and taurine-conjugated BAs have also been implicated in the modulation of cardiovascular functions. This brief review summarizes the role of taurine and taurine-conjugated BAs in vascular relaxation through the modulation of endothelium-derived nitric oxide (NO). The effects of taurine on vascular health are controversial. However, in the presence of cardiometabolic risk factors, it has been proposed that taurine can increase vascular NO levels by increasing eNOS expression, eNOS phosphorylation on Ser1177, NO bioavailability, the level of antioxidative defense, and the l-arginine/NOS inhibitor asymmetric dimethylarginine (ADMA) ratio. The taurine-conjugated BA-mediated activation of Farnesoid X receptor (FXR), G protein-coupled BA receptor (TGR5) and/or muscarinic 3 receptor (M3) was also reported to increase vascular NO production. FXR activation increases eNOS expression and may reduce ADMA formation, while TGR5 increases mobilization of Ca²⁺ and phosphorylation of eNOS and Akt in endothelial cells. Furthermore, taurine and taurine-conjugated BAs might regulate NO synthesis and activity by enhancing H₂S generation. Several studies have demonstrated the beneficial effects of both taurine and taurine-conjugated BAs in reversing the endothelial dysfunction associated with diabetes, atherosclerosis, hypertension, obesity, malnutrition, and smoking. In addition, taurine-conjugated BAs have emerged as a potential treatment for portal hypertension. Despite these favorable findings, there is a need to further explore the mechanisms and signaling pathways underlying the endothelial effects of taurine and taurine-conjugated BAs. Here, we summarize the main findings regarding the effects of taurine and taurine-conjugated BAs on the endothelial dysfunction associated with altered NO metabolism in cardiovascular diseases.

Hydrogen sulfide regulation of renal and mesenteric blood flow

Hydrogen sulfide (H₂S) dilates isolated arteries, and knockout of the H₂S-synthesizing enzyme cystathionine γ-lyase (CSE) increases blood pressure. However, the contributions of endogenously produced H₂S to blood flow regulation in specific vascular beds are unknown. Published studies in isolated arteries show that CSE production of H₂S influences vascular tone more in small mesenteric arteries than in renal arteries or the aorta. Therefore, the goal of this study was to evaluate H₂S regulation of blood pressure, vascular resistance, and regional blood flows using chronically instrumented rats. We hypothesized that during whole animal CSE inhibition, vascular resistance would increase more in the mesenteric than the renal circulation. Under anesthesia, CSE inhibition [β-cyanoalanine (BCA), 30 mg/kg bolus + 5 mg·kg^-1·min^-1 for 20 min iv) rapidly increased mean arterial pressure (MAP) more than saline administration (%Δ: saline -1.4 ± 0.75 vs. BCA 7.1 ± 1.69, P < 0.05) but did not change resistance (MAP/flow) in either the mesenteric or renal circulation. In conscious rats, BCA infusion similarly increased MAP (%Δ: saline -0.8 ± 1.18 vs. BCA 8.2 ± 2.6, P < 0.05, n = 7) and significantly increased mesenteric resistance (saline 0.9 ± 3.1 vs. BCA 15.6 ± 6.5, P < 0.05, n = 12). The H₂S donor Na₂S (50 mg/kg) decreased blood pressure and mesenteric resistance ,but the fall in resistance was not significant. Inhibiting CSE for multiple days with dl-proparglycine (PAG, 50 mg·kg^-1·min^-1 iv bolus for 5 days) significantly increased vascular resistance in both mesenteric (ratio of day 1: saline 0.86 ± 0.033 vs. PAG 1.79 ± 0.38) and renal circulations (ratio of day 1: saline 1.26 ± 0.22 vs. 1.98 ± 0.14 PAG). These results support our hypothesis that CSE-derived H₂S is an important regulator of blood pressure and vascular resistance in both mesenteric and renal circulations. Furthermore, inhalation anesthesia diminishes the effect of CSE inhibition on vascular tone.NEW & NOTEWORTHY These results suggest that CSE-derived H₂S has a prominent role in regulating blood pressure and blood flow under physiological conditions, which may have been underestimated in prior studies in anesthetized subjects. Therefore, enhancing substrate availability or enzyme activity or dosing with H₂S donors could be a novel therapeutic approach to treat cardiovascular diseases.