Potential mechanisms of the anti-hypertensive effects of RVPSL on spontaneously hypertensive rats using non-targeted serum metabolomics

Integrated Microbiome and Serum Metabolome Analysis Reveals Molecular Regulatory Mechanisms of the Average Daily Weight Gain of Yorkshire Pigs

The average daily weight gain (ADG) is considered a crucial indicator for assessing growth rates in the swine industry. Therefore, investigating the gastrointestinal microbiota and serum metabolites influencing the ADG in pigs is pivotal for swine breed selection. This study involved the inclusion of 350 purebred Yorkshire pigs (age: 90 ± 2 days; body weight: 41.20 ± 4.60 kg). Concurrently, serum and fecal samples were collected during initial measurements of blood and serum indices. The pigs were categorized based on their ADG, with 27 male pigs divided into high-ADG (HADG) and low-ADG (LADG) groups based on their phenotype values. There were 12 pigs in LADG and 15 pigs in HADG. Feces and serum samples were collected on the 90th day. Microbiome and non-targeted metabolomics analyses were conducted using 16S rRNA sequencing and liquid chromatography-mass spectrometry (LC-MS). Pearson correlation, with Benjamini-Hochberg (BH) adjustment, was employed to assess the associations between these variables. The abundance of Lactobacillus and Prevotella in LADG was significantly higher than in HADG, while Erysipelothrix, Streptomyces, Dubosiella, Parolsenella, and Adlercreutzia in LADG were significantly lower than in HADG. The concentration of glutamine, etiocholanolone glucuronide, and retinoyl beta-glucuronide in LADG was significantly higher than in HADG, while arachidonic acid, allocholic acid, oleic acid, phenylalanine, and methyltestosterone in LADG were significantly lower than in HADG. The Lactobacillus-Streptomyces networks (Lactobacillus, Streptomyces, methyltestosterone, phenylalanine, oleic acid, arachidonic acid, glutamine, 3-ketosphingosine, L-octanoylcarnitine, camylofin, 4-guanidinobutyrate 3-methylcyclopentadecanone) were identified as the most influential at regulating swine weight gain. These findings suggest that the gastrointestinal tract regulates the daily weight gain of pigs through the network of Lactobacillus and Streptomyces. However, this study was limited to fecal and serum samples from growing and fattening boars. A comprehensive consideration of factors affecting the daily weight gain in pig production, including gender, parity, season, and breed, is warranted.

Study on material basis and anti-hypertensive metabolomics of different extraction methods of the Uncaria rhynchophylla Scrophularia Formula

Hypertension is one of the most challenging public health problems worldwide. Previous studies suggested that the Uncaria rhynchophylla Scrophularia Formula (URSF), a medical institution preparation of the affiliated Hospital of Shandong University of Traditional Chinese Medicine, is effective for essential hypertension. However, the efficacy of URSF for hypertension remains unclear. We aimed to clarify the anti-hypertensive mechanism of the URSF. The material basis of URSF was identified by the LC-MS. We also evaluated the antihypertensive efficacy of URSF on SHR rats by body weight, blood pressure and biochemical indicators. The LC-MS spectrometry-based serum non-targeted metabolomics was used to seek potential biomarkers and relevant pathways for URSF in the treatment of SHR rats. 56 biomarkers were metabolically disturbed in SHR rats in the model group compared with the control group. After URSF intervention, 13 biomarkers showed a recovery in the optimal method compared with the other three groups. We identified 3 metabolic pathways in which URSF is involved: the arachidonic acid metabolism pathway, the niacin and nicotinamide metabolism pathway, and the purine metabolism pathway. These discoveries offer a basis for the study of URSF for the treatment of hypertension.

Altered adolescents obesity metabolism is associated with hypertension: a UPLC-MS-based untargeted metabolomics study

Objective

This study aimed to explore the relationship between the plasma metabolites of adolescent obesity and hypertension and whether metabolite alterations had a mediating effort between adolescent obesity and hypertension.

Methods

We applied untargeted ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) to detect the plasma metabolomic profiles of 105 adolescents. All participants were selected randomly based on a previous cross-sectional study. An orthogonal partial least squares- discriminant analysis (OPLS-DA), followed by univariate statistics and enrichment analysis, was used to identify differential metabolites. Using logistic regression for variable selection, an obesity-related metabolite score (OMS, OMS=∑k=1nβnmetabolite n) was constructed from the metabolites identified, and hypertension risk was estimated.

Results

In our study, based on P< 0.05, variable importance in projection (VIP) > 1.0, and impact value > 0.1, we identified a total of 12 differential metabolites. Significantly altered metabolic pathways were the sphingolipid metabolism, purine metabolism, pyrimidine metabolism, phospholipid metabolism, steroid hormone biosynthesis, tryptophan, tyrosine, and phenylalanine biosynthesis. The logistic regression selection resulted in a four-metabolite score (thymidine, sphingomyelin (SM) d40:1, 4-hydroxyestradiol, and L-lysinamide), which was positively associated with hypertension risk (odds ratio: 7.79; 95% confidence interval: 2.13, 28.47; for the quintile 4 compared with quartile 1 of OMS) after multivariable adjustment.

Conclusions

The OMS constructed from four differential metabolites was used to predict the risk of hypertension in adolescents. These findings could provide sensitive biomarkers for the early recognition of hypertension in adolescents with obesity.

Small molecule metabolites: discovery of biomarkers and therapeutic targets

Metabolic abnormalities lead to the dysfunction of metabolic pathways and metabolite accumulation or deficiency which is well-recognized hallmarks of diseases. Metabolite signatures that have close proximity to subject's phenotypic informative dimension, are useful for predicting diagnosis and prognosis of diseases as well as monitoring treatments. The lack of early biomarkers could lead to poor diagnosis and serious outcomes. Therefore, noninvasive diagnosis and monitoring methods with high specificity and selectivity are desperately needed. Small molecule metabolites-based metabolomics has become a specialized tool for metabolic biomarker and pathway analysis, for revealing possible mechanisms of human various diseases and deciphering therapeutic potentials. It could help identify functional biomarkers related to phenotypic variation and delineate biochemical pathways changes as early indicators of pathological dysfunction and damage prior to disease development. Recently, scientists have established a large number of metabolic profiles to reveal the underlying mechanisms and metabolic networks for therapeutic target exploration in biomedicine. This review summarized the metabolic analysis on the potential value of small-molecule candidate metabolites as biomarkers with clinical events, which may lead to better diagnosis, prognosis, drug screening and treatment. We also discuss challenges that need to be addressed to fuel the next wave of breakthroughs.

Dissecting the potential mechanism of antihypertensive effects of RVPSL on spontaneously hypertensive rats via widely targeted kidney metabolomics

BACKGROUND

Our previous study has demonstrated that the egg-white-derived peptide RVPSL can lower blood pressure in spontaneously hypertensive rats (SHRs), but its potential action mechanism remains unclear. In this work, the underlying mechanism of the antihypertensive effects of RVPSL in SHRs was elucidated using the widely targeted kidney metabolomics approach.

RESULTS

Ten SHRs were divided into two groups: SHR-Untreated group (0.9% saline) and SHR-RVPSL group (50 mg kg^-1 body weight RVPSL) for 4 weeks. After 4 weeks, kidney samples were collected and widely targeted (liquid chromatography-electrospray ionization-tandem mass spectrometry) metabolomics was used to detect metabolites. Fifty-six biomarkers were identified that may be associated with hypertension. Among them, 17 biomarkers were upregulated and 39 biomarkers were downregulated. The results suggested that eight potential biomarkers were identified in kidney samples: O-phospho-l-serine, tyramine, citric acid, 3-hydroxybutyrate, O-acetyl-l-serine, 15-oxo-5Z,8Z,11Z,13E-eicosatetraenoic acid (15-oxoETE), dopaquinone and 3,3',5-triiodo-l-thyronine. These potential biomarkers mainly involved carbon metabolism, thyroid hormone signaling pathway, tyrosine metabolism and arachidonic acid metabolism.

CONCLUSION

The study suggested that RVPSL may exert antihypertensive effects through upregulation of O-phospho-l-serine, 3-hydroxybutyrate and 15-oxoETE, and downregulation of tyramine, citric acid, O-acetyl-l-serine, 3,3',5-triiodo-l-thyronine and dopaquinone. The antihypertensive effects of RVPSL may be related to carbon metabolism, thyroid hormone signaling pathway, tyrosine metabolism and arachidonic acid metabolism. RVPSL exhibited a potent antihypertensive effect, and the antihypertensive effects were associated with inhibition of vascular smooth muscle cell proliferation, vascular remodeling, vascular endothelium dysfunction, restoring reactive oxygen species, oxidative stress, inflammation and immune reaction. © 2022 Society of Chemical Industry.

Potential antihypertensive mechanism of egg white-derived peptide QIGLF revealed by proteomic analysis

Previous work has shown that egg white-derived peptide QIGLF has significant in vivo antihypertensive activity. This study aimed to clarify the antihypertensive mechanisms of QIGLF on spontaneously hypertensive rats (SHRs) by a serum proteomic approach. Here, the tandem mass tag (TMT) quantitative proteomic was performed to discover serum protein changes in SHRs with QIGLF. As a result, SHRs with 4 weeks of QIGLF treatment have distinct serum protein expression profiles by principal component and Pearson's correlation coefficient analysis. Based on Gene Ontology (GO) annotation, oxygen transport and organelle fusion were found to be a regulated major biological process. Besides, aldosterone regulated sodium reabsorption, mitophagy, gap junction, and tight junction were significantly regulated based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. QIGLF might exert antihypertensive effects in the SHRs by inhibiting Na+ reabsorption and oxidative stress, restoring gap junction and tight junction.

Underlying antihypertensive mechanism of egg white-derived peptide QIGLF using renal metabolomics analysis

The kidney is an important target organ in the treatment of hypertension, but the effect of peptide QIGLF with antihypertensive activity on kidneys remains unknown. In the work, we aimed to further understand the hypotensive effects of QIGLF in spontaneously hypertensive rats (SHRs) using widely targeted metabolomics technology to investigate the kidney metabolic profiling variations. After four weeks of oral administration, the results showed different renal metabolomics profiles between QIGLF and model groups. Besides, a total of 10 potential biomarkers were identified, that is, 3-hydroxybutanoate, 20-hydroxyeicosatetraenoic acid, 19(S)-hydroxyeicosatetraenoic acid, 15-oxoETE, L-ornithine, malonate, uridine, uridine 5'-monophosphate, argininosuccinic acid, and N-carbamoyl-L-aspartate. These metabolites might exhibit antihypertensive activity of QIGLF by regulating synthesis and degradation of ketone bodies, arachidonic acid metabolism, pyrimidine metabolism, and arginine biosynthesis. These findings suggest that QIGLF might alleviate hypertension by inhibiting renal inflammation, promoting natriuresis, and regulating renal nitric oxide production.

Antihypertensive effect and underlying mechanism of tripeptide NCW on spontaneously hypertensive rats using metabolomics analysis

Tripeptide NCW identified in our previous study displayed a strong ACE inhibitory activity, but whether it has any antihypertensive effect in vivo remains unknown. Thus, in this study, we aimed to investigate the protective effects of tripeptide NCW in spontaneously hypertensive rats (SHRs) and to further figure out the serum metabolic profiling variations due to its oral administration via UPLC-Q-TOF-MS/MS-based metabolomics analysis to clarify the underlying hypotensive mechanism. After three weeks of oral administration, the tripeptide NCW-treated group (NCW/SHR group, 80 mg per kg BW per d) showed significantly reduced systolic and diastolic blood pressure by 48.08 ± 3.84 mmHg and 48.92 ± 5.77 mmHg, respectively. Additionally, a total of 25 blood pressure-related metabolites were identified as being significantly changed in SHRs given tripeptide NCW after three weeks. These 25 metabolites might be biomarkers that indicated that the tripeptide NCW exhibits antihypertensive activity via regulating bile acid metabolism, lipid metabolism, amino acid metabolism, purinergic signaling, pantothenate and CoA biosynthesis, and the citrate cycle. Collectively, tripeptide NCW has a protective effect on SHRs associated with serum metabolite abnormalities.

Potential Antihypertensive Mechanisms of the Egg White-Derived Peptide QIGLF in Spontaneously Hypertensive Rats Revealed Using Untargeted Serum Metabolomics

The angiotensin-converting enzyme (ACE) inhibitory peptide QIGLF derived from egg white was shown to have significant in vivo antihypertensive effects in our previous study, but the intervention mechanisms at the metabolic level are still unclear. The UPLC-QTOF/MS-based untargeted metabolomics approach was used to clarify the potential antihypertensive mechanisms of QIGLF in the serum of spontaneously hypertensive rats (SHRs). Multivariate statistical analysis showed a clear difference in the metabolite profiles between the QIGLF and model groups. The results suggested that eight potential biomarkers were identified, that is, adrenic acid, ursodeoxycholic acid, glycocholic acid, taurocholic acid, tryptophan, acetylindoxyl, tyrosine, and 2-phenylethanol, which were mainly involved in aromatic amino acid biosynthesis and metabolism, biosynthesis of bile acid, and biosynthesis of unsaturated fatty acids. QIGLF might exert antihypertensive effects by improving endothelial dysfunction. This study provides a theoretical basis for future research and application of ACE inhibitory peptides in the prevention and improvement of hypertension.