The case for metabolic hypertension: is it time to restructure the hypertension paradigm?

Atractylodes macrocephala Koidz polysaccharide improves glycolipid metabolism disorders through activation of aryl hydrocarbon receptor by gut flora-produced tryptophan metabolites

Polysaccharides are known to confer protection against glycolipid metabolism disorders (GMD) by regulating intestinal flora. In this study, a heterogeneous acidic heteropolysaccharide with high molecular weight mainly composed of fructose was isolated from Atractylodes macrocephala Koidz (AMP). Supplementation with AMP was shown to improve diet-induced GMD in a rat model, including decreasing the levels of serum triglycerides, total cholesterol, and glucose, and improving hepatic lipidosis and islet cells morphologies. AMP-treated rats also exhibited modified intestinal flora with enrichments of intestinal Lactobacillus and Rothia species, which was accompanied by increased tryptophan metabolites such as indole-3-propionic acid, indole, tryptamine, and tryptophol. These metabolites promote the expression of intestinal aryl hydrocarbon receptor (AhR) in nuclear fractions. AhR activation increased the expression levels of IL-22 and GLP-1 proteins and mRNA. IL-22 reduced systemic LPS by upregulating the expression of tight junction proteins, antimicrobial peptides, and mucin to ameliorate intestinal barrier function, and activated the hepatic IL-22R/Stat3/Acox1 signaling pathway to improve lipid metabolism. GLP-1 activated the pancreatic GLP-1R/p-CREB signaling pathway to ameliorate β-cell injury and improve insulin resistance. Therefore, the intestinal microbial-tryptophan metabolism-AhR pathway was deduced to be a mechanism by which this polysaccharide improves GMD.

Beneficial effects of Panax notoginseng (Burkill) F. H. Chen flower saponins in rats with metabolic hypertension by inhibiting the activation of the renin-angiotensin-aldosterone system through complement 3

BACKGROUND

Metabolic hypertension (MH) has become the most common type of hypertension in recent years due to unhealthy eating habits and lifestyles of people, such as over-eating alcohol, high fat, and sugar diets (ACHFSDs). Therefore, effective means to combat MH are needed. Previous studies have shown that Panax notoginseng (Burkill) F. H. Chen flower saponins (PNFS) can lower blood pressure in spontaneously hypertensive rats (SHR). However, whether it acts on MH and its mechanism of action remain unclear.  METHODS: The pharmacodynamic effects of PNFS were evaluated in rats with ACHFSDs-induced MH. The blood pressure, blood biochemical, grip strength, face temperature, vertigo time, and liver index were estimated. The histological changes in the liver and aorta were observed using hematoxylin and eosin staining. The levels of ET-1, TXB₂, NO, PGI₂, Renin, ACE, Ang II, and ALD in plasma were detected using ELISA. The levels of C3, KLF5, LXRα, and Renin in kidney tissues were measured using qRT-PCR.The expression levels of C3, KLF5, LXRα, and Renin in kidney tissues were examined using Western blotting.

RESULTS

In the present study, PNFS was found to reduce blood pressure, face temperature, and vertigo time, increase grip strength and improve dyslipidemia in rats with MH. In addition, PNFS decreased the plasma levels of ET-1 and TXB₂, elevated the levels of NO and PGI₂, and improved pathological aortic injury. Meanwhile, PNFS decreased the plasma levels of Renin, ACE, Ang II, and ALD. QRT-PCR and Western bolt showed that PNFS downregulated C3, KLF5, LXRα, and Renin protein and mRNA expression in the kidneys of rats with MH.

CONCLUSION

The finding of the present study suggested that PNFS could downregulate C3 and KLF-5 expression in rats with MH, thereby inhibiting the overactivation of the renin-angiotensin-aldosterone system, while improving vascular endothelial function and ultimately reducing blood pressure in rats with MH.

Buddleoside-Rich Chrysanthemum indicum L. Extract has a Beneficial Effect on Metabolic Hypertensive Rats by Inhibiting the Enteric-Origin LPS/TLR4 Pathway

As the number of patients with metabolic hypertension (MH) is increasing, there is an essential require for global measures to prevent and treat MH. Flavonoids such as buddleoside (BUD) from Chrysanthemum indicum L. are the main pharmacological components of cardiovascular activities. Previous studies have suggested that the buddleoside-rich Chrysanthemum indicum L. extract (BUDE) can reduce blood pressure in spontaneously hypertensive rats (SHR). However, its effect on MH and how it works remains to be researched. In this study, it was observed that BUDE could lower blood pressure, improve dyslipidemia, and decrease the level of plasma LPS in MH rats. Moreover, BUDE improved intestinal flora and increased the expression of occludin and claudin-1 in the colon, and improved the pathological injury of the colon. Western bolt and qRT-PCR experiments showed that BUDE could down-regulate TLR4 and MyD88 protein and mRNA expression and inhibit phosphorylation of IKKβ, IκBα and NF-κB p65 in vessels of MH rats. These results showed that BUDE could regulate intestinal flora, improve intestinal barrier function, reduce the production and penetration of LPS, thereby inhibiting the vascular TLR4/MyD88 pathway, improving vascular endothelial function, and ultimately lowering blood pressure in MH rats. This study provides a new mechanism of BUDE against MH by inhibiting the enteric-origin LPS/TLR4 pathway.

Beneficial effects of Dendrobium officinale on metabolic hypertensive rats by triggering the enteric-origin SCFA-GPCR43/41 pathway

Given the increasing global trend toward unhealthy lifestyles and dietary decisions, such as "over-consumption of alcohol, and high sugar and fat diets" (ACHSFDs), it is not surprising that metabolic hypertension (MH) is now the most common type of hypertension. There is an urgent, global need for effective measures for the prevention and treatment of MH. Improper diet leads to decreased short-chain fatty acid (SCFA) production in the gut, leading to decreased gastrointestinal function, metabolism, and blood pressure as a result of signaling through G-protein-coupled receptors (GPCRs), ultimately causing MH. Previous studies have suggested that Dendrobium officinale (DO) may improve gastrointestinal function, lower blood pressure, and regulate metabolic abnormalities, but it is not clear whether it acts on MH by increasing SCFA and, if so, how. In this research, it was observed that Dendrobium officinale ultrafine powder (DOFP) could lower blood pressure and improve lipid abnormalities in ACHSFD-induced MH model rats. Moreover, DOFP was found to improve the intestinal flora and increased the SCFA level in feces and serum, as well as increased the expressions of GPCR43/41 and eNOS and the nitric oxide (NO) level. An experiment on isolated aorta rings revealed that DOFP improved the vascular endothelial relaxation function in MH rats, and this effect could be blocked by the eNOS inhibitor l-NAME. These experimental results suggest that DOFP improved the intestinal flora and increased the production, transportation, and utilization of SCFA, activated the intestinal-vascular axis SCFA-GPCR43/41 pathway, improved vascular endothelial function, and finally lowered blood pressure in MH model rats. This research provides a new focus for the mechanism of the effect of DOFP against MH by triggering the enteric-origin SCFA-GPCR43/41 pathway.

Systematic Understanding of the Mechanisms of Flos Chrysanthemi Indici-mediated Effects on Hypertension via Computational Target Fishing

AIMS AND OBJECTIVE

Hypertension-induced stroke and coronary artery disease are significant causes of global morbidity and mortality. Metabolic hypertension has recently become the leading cause of hypertension. Flos Chrysanthemi Indici (CIF) has a long history as a treatment of hypertension as part of traditional Chinese medicine. However, its mechanisms of activity remain largely unknown. This study was aimed to uncover the potential anti-hypertensive mechanisms of CIF based on network pharmacology.

MATERIALS AND METHODS

In this research, a systems pharmacology approach integrating the measurement of active compounds, target fishing, gene screening, Gene Ontology (GO) pathway analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) Orthology Based Annotation System (KOBAS) database analysis, and compound-target network construction were performed to explore the anti-hypertensive mechanisms of CIF.

RESULTS

These studies revealed that 12 bioactive compounds in CIF had good druggability, 5 of which were flavonoids. After screening, 8 of those 12 bioactive compounds interacted with 118 hypertensionrelated target genes, which were mapped to 218 signal pathways. Network analysis showed that these targets were associated with improving insulin resistance, improving vascular function, inhibiting renninangiotensin- aldosterone system (RAAS), inhibiting the sympathetic nervous system (SNS) and regulating other physiological processes.

CONCLUSION

In summary, CIF is predicted to target multiple proteins and pathways to form a network that exerts systematic pharmacological effects in order to regulate blood pressure and metabolic disorder.

Retinopathy in type 1 diabetes mellitus: Major differences between rural and urban dwellers in northwest Ethiopia

AIM

To audit levels of diabetes-related eye disease in Type 1 diabetes mellitus (T1DM) patients in northwest Ethiopia. In particular to establish whether, despite identical clinical goals, major differences between the physically demanding life-style of rural subsistence farmers and the sedentary life-style of urban dwellers would influence the prevalence of diabetes-related eye complications.

METHODS

A robust infrastructure for chronic disease management that comprehensively includes all rural dwellers was a pre-requisite for the investigation. A total of 544 T1DM were examined, representing 80% of all T1DM patients under regular review at both the urban and rural clinics and representative of patient age and gender (62.1% male, 37.9% female) of T1DM patients from this region; all were supervised by the same clinical team. Eye examinations were performed for visual acuity, cataract and retinal changes (retinal photography). HbA1c levels and the presence or absence of hypertension were recorded.

RESULTS/CONCLUSIONS

Urban and rural groups had similar prevalences of severe visual impairment/blindness (7.0% urban, 5.2% rural) and cataract (7.3% urban, 7.1% rural). By contrast, urban dwellers had a significantly higher prevalence of retinopathy compared to rural patients, 16.1% and 5.0%, respectively (OR 2.9, p<0.02, after adjustment for duration, age, gender and hypertension). There was a 3-fold greater prevalence of hypertension in urban patients, whereas HbA1c levels were similar in the two groups. Since diabetic retinopathy is closely associated with microvascular disease and endothelial dysfunction, the possible influences of hypertension to increase and of sustained physical activity to reduce endothelial dysfunction are discussed.

Mechanism and effect of shijueming (Concha Haliotidis) on serum calcium in spontaneously hypertensive rats

OBJECTIVE

To observe the impact of Shijueming (Concha Haliotidis) on spontaneously hypertensive rats via blood pressure, serum calcium, vascular smooth muscle membrane L-type calcium channel alpha1 C subunit (CaL-alpha1C), plasma membrane calcium-ATPase (PMCA) mRNA expression, and the L-type calcium channel in vascular smooth muscle cells.

METHODS

Twelve-week-old male rats with spontaneous hypertension were divided into three groups: a Shijueming (Concha Haliotidis) group (group 1), a nifedipine group (group 2), and a distilled water group (group 3). All were given a four-week treatment. Blood pressure and dissociative serum calcium were examined before treatment. Blood pressure was taken every week during treatment. Atomic absorption spectrometry was used to examine dissociative serum calcium. Reverse transcription-polymerase chain reaction was used to examine the expression of CaL-alpha1C and PMCA1 mRNA. The patch clamp technique was used to examine the electrophysiological characteristics of the vascular smooth muscle cell calcium channels.

RESULTS

After treatment, blood pressure of the Shijueming (Concha Haliotidis) group lowered but not significantly (P > 0.05). Blood pressure of the nifedipine group lowered significantly (P < 0.05). Blood pressure of the distilled water group remained high. The concentration of serum calcium in the Shijueming (Concha Haliotidis) and the distilled water groups lowered (P < 0.05). Expression of CaL-alpha1C mRNA in the nifedipine group decreased compared with the distilled water group (P < 0.01). There was the decreasing trend in the Shijueming (Concha Haliotidis) group, but it was not statistically significant. Shijueming (Concha Haliotidis) also had effects on the expression of PMCA1 mRNA but without statistical significance. However, there was a significant decreasing effect on vascular smooth muscle cell I(Ca)-L flow.

CONCLUSION

This study indicated that Shijueming (Concha Haliotidis) could increase serum calcium and decrease blood pressure. It may work by influencing calcium channels, expression of PMCA1 mRNA, and regulating ion calcium channels and calcium-ATPase.

Metabolic hypertension: concept and practice

Hypertension is a serious public health problem worldwide. More than 60% of the risk factors for hypertension are associated with metabolic disturbances. Metabolic abnormalities increase the risk for hypertension and cause high blood pressure. Improving metabolic disturbances is beneficial for hypertension treatment. Due to the importance of metabolic abnormalities in the pathogenesis of hypertension, we propose a concept of metabolic hypertension. In this review, we discuss and review the clinical types, pathogenesis, risk evaluation and management of metabolic hypertension. Elucidation of the mechanism of metabolic hypertension should facilitate the design of novel pharmacotherapeutics and dedicated antihypertensive manipulations.

Family-based randomized trial to detect effects on blood pressure of a salt substitute containing potassium and calcium in hypertensive adolescents

BACKGROUND

Potassium and calcium are important in blood pressure (BP) regulation. The aim of this study was to test the effects on BP of adding potassium and calcium to dietary salt.

METHODS

A total of 325 adolescents selected with high BP (systolic BP (SBP) >or=90th percentile by age and sex) along with 978 family members. The adolescents were randomized into three groups by coin toss, and their families (300 total) were also allocated to the three groups: one in which 10 mmol of potassium and 10 mmol of calcium were added to the cooking salt, one encouraged to follow a salt-restricted diet, and a control group. In the salt-restricted group, salt intake was decreased gradually through health-behavior education to reach the goal of 50-100 mmol per person per day at 2 years. No intervention took place in for the control group. Salt sensitivity was determined by a volume expansion and contraction protocol at the beginning of the study. The three groups were followed up every 6 months for 2 years.

RESULTS

At 2 years, systolic and diastolic blood pressure (SBP/DBP) had decreased by 5.9/2.8 mm Hg (4.7/3.6%) in the added-potassium-and-calcium group and by 5.8/1.0 mm Hg (4.8/1.4%) in the salt-restricted group; the values rose in the control group by 1.3/2.3 mm Hg (1.1/1.8%). There was no difference between the added-potassium-and-calcium group and the restricted-salt group (P = 0.24), but both differed significantly from the controls (P < 0.05). Similar changes in BP were found in family members. Subgroup analysis showed that the BP in salt-sensitive (SS) subjects decreased more than in the non-salt-sensitive (NSS) group (P < 0.05).

CONCLUSION

A salt substitute containing potassium and calcium was as effective as sodium restriction in reducing BP in hypertensive adolescents and their families in a that rural Chinese community.

Reduction of blood pressure with calcium and potassium supplementation in children with salt sensitivity: a 2-year double-blinded placebo-controlled trial

An investigation of the reductive effect of blood pressure and increment of urinary sodium excretion with calcium and potassium supplementation in children with sodium sensitivity is conducted. In total of 261 school children who had completed a 2-year double-blinded, placebo-controlled trial with calcium and potassium supplementation salt sensitivity, with a salt volume expansion and contraction protocol, was determined. The results showed that in children with salt sensitivity, the increase in blood pressure in the supplementary group was lower by 4.3/4.8 mmHg than that in the placebo group (P<0.05), while no significant change was found between the supplementary group and placebo group in children with nonsalt sensitivity. With calcium and potassium supplementation, the night urinary sodium excretion in children with salt sensitivity was significantly increased (P<0.01), and it is negatively correlated with the increase in blood pressure. It was suggested that a moderate increase of calcium and potassium intake in children with salt sensitivity, through interaction with sodium, can promote urinary sodium excretion and may play contribute to the prevention of hypertension.

Calcium channel blockers and hypertension: evolving perspective--1996

In recent years, calcium channel blockers (CCBs) have been used extensively in the United States and elsewhere as antihypertensive agents, and their availability has been an important advance in the management of hypertension. As antihypertensive agents, the CCBs thus appear considerably more versatile than most previous vasodilators. The available studies indicate that CCBs are metabolically neutral and do not exacerbate dyslipidemia or impair glucose tolerance. In contrast to diuretics and beta-blockers, CCBs do not appear to alter insulin sensitivity. The CCBs also differ from previous vasodilators because of their favorable accompanying effects on the heart and kidney. Despite the attributes of CCBs enumerated earlier, a number of recent retrospective analyses by Psaty et al. (JAMA 1995;274:620-625) have suggested that CCBs may be detrimental and may promote adverse cardiovascular events. I have recently reviewed the results of Psaty's meta-analysis and report (Arch Intern Med 1995;155: 2150-2156). I have emphasized that it is the rate of drug delivery into the systemic circulation that produces profound effects on the hemodynamic and neurohumoral responses to a dihydropyridine CCB drug. During chronic treatment with dihydropyridines, major fluctuations in blood pressure (rapid onset and offset of antihypertensive effects) during the dosing interval may persist for drugs and formulations that are short acting. In contrast, slow-release formulations of otherwise rapidly absorbed dihydropyridines achieve a more gradual and sustained antihypertensive effect. It is probable that newer CCB formulations that do not provoke intermittent sympathetic activation and do not evoke a cardioacceleratory response would not be expected to promote adverse cardiovascular events.

Kidney disease in the first-degree relatives of African-Americans with hypertensive end-stage renal disease

The incidence of treated end-stage renal disease (ESRD) in the United States is four times more frequent in African-Americans (AAs) than in whites. This is explained neither by a greater prevalence of hypertension and diabetes mellitus nor by socioeconomic issues. To investigate familial risk of renal disease in AAs, we examined the records of 472 AA dialysis patients in Jefferson County, Alabama. Applying strict criteria, we identified 85 index cases of ESRD associated only with hypertension (H-ESRD). We examined the records of 75 index cases and studied the first-degree relatives of 40 patients. The numbers of men and women with H-ESRD were similar (38 and 37, respectively). There was no statistical difference in age at the onset of dialysis (women 53.7 +/- 13.5 years [+/-SD] and men 49.2 +/- 12.2 years; P = 0.0863). We found evidence for renal disease in 26 of 40 (65%) index cases with participating families. Hypertension was present in all 40 families (100%) and diabetes mellitus was present in 24 families (60%). Eighteen of the 75 H-ESRD index patients had a first-degree relative with ESRD. In total, we found evidence for renal disease in 35 of 75 (47%) We conclude that there is a strong concordance of renal disease in the families of AAs with H-ESRD.

Diet and exercise intervention have favourable effects on blood pressure in mild hypertensives: the Oslo Diet and Exercise Study (ODES)

The purpose of this study was to investigate the effect of 1-year diet intervention, exercise intervention and both combined on blood pressure (BP) in normotensives and mild hypertensives. Two hundred and nineteen sedentary middle aged men and women with slightly deranged coronary heart disease (CHD) risk factors were randomised to a control, a diet, an exercise and a diet + exercise group. Based on baseline diastolic BP, participants were divided into tertiles, giving baseline average BP of 141.4/96.7 in tertile 1, 130.7/87.6 in tertile 2 and 121.9/79.0 in tertile 3. The 1-year net-difference in BP between the intervention groups and the control group decreased across the tertiles; in tertile 1 being -11.2/-6.7 (p < 0.05), -11.3/-6.7 (p < 0.05 for systolic BP only) and -7.0/-5.1 (NS) in the combined, diet and exercise group respectively. Triglycerides, HDL cholesterol, and insulin variables were significantly and favourably changed, the changes being most marked in the combined group. The results show that diet and diet + exercise are about equally effective in reducing BP, and the effects may be dependent on the baseline level. Within the upper tertile of baseline BP, the decline in BP in the combined intervention and the diet group are almost comparable to those obtained with drug treatment. In addition, other important CHD risk factors were all changed in a beneficial direction.