UPLC/MS-Based Metabolomics Investigation of the Protective Effect of Hydrogen Gas Inhalation on Mice with Calcium Oxalate-Induced Renal Injury

Application of Electrolyzed Hydrogen Water for Management of Chronic Kidney Disease and Dialysis Treatment-Perspective View

Chronic kidney disease (CKD), which is globally on the rise, has become an urgent challenge from the perspective of public health, given its risk factors such as end-stage renal failure, cardiovascular diseases, and infections. The pathophysiology of CKD, including dialysis patients, is deeply associated with enhanced oxidative stress in both the kidneys and the entire body. Therefore, the introduction of a safe and widely applicable antioxidant therapy is expected as a measure against CKD. Electrolyzed hydrogen water (EHW) generated through the electrolysis of water has been confirmed to possess chemical antioxidant capabilities. In Japan, devices producing this water have become popular for household drinking water. In CKD model experiments conducted to date, drinking EHW has been shown to suppress the progression of kidney damage related to hypertension. Furthermore, clinical studies have reported that systemic oxidative stress in patients undergoing dialysis treatment using EHW is suppressed, leading to a reduction in the incidence of cardiovascular complications. In the future, considering EHW as one of the comprehensive measures against CKD holds significant importance. The medical utility of EHW is believed to be substantial, and further investigation is warranted.

Studies on the mechanism of Panax Ginseng in the treatment of deficiency of vital energy dementia rats based on urine metabolomics

Panax Ginseng (PG) has been used to strengthen memory and physique for thousands of years, because its main components ginsenosides (GS) and ginseng polysaccharides (GP) play a major role, but its mechanism is not clear. In this study, a rat model of dementia with vital energy deficiency (DED) was established through intraperitoneal injection with D-galactose and AlCl₃ and combined with exhaustive swimming. Pharmacological studies and the urine metabolomics based on ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) were employed for evaluation the efficacy of PG and exploring this treatment mechanism. Through urine metabolic profiling, it can be seen that DED rats after PG administration are close to normal group (NG) rats, and PG can regulate the in vivo status of DED rats which tend to NG. The results of behavioral, biochemical indicators and immunohistochemistry further verified the above results, and the mechanism of action of each component is refined. Ultimately, we believe that the mechanism of PG in the treatment of DED is that ginsenosides (GS) intervenes in phenylalanine tryptophan and tyrosine metabolism, stimulates dopamine production, inhibits Aβ deposition and neuroinflammation; and that ginseng polysaccharides (GP) provides energy to strengthen the TCA cycle and improve immune capacity.

Oral Hydrogen-Rich Water Alleviates Oxalate-Induced Kidney Injury by Suppressing Oxidative Stress, Inflammation, and Fibrosis

Objective: To explore the theraputic effects and potential mechanisms of hydrogen-rich water (HRW) against oxalate-induced kidney injury.

Methods: The mouse model of Calcium oxalate (CaOx) crystallization was established by feeding a soluble oxalate diet. Crystal deposition, tubular injury, fibrosis and reactive oxygen species (ROS) production in kidneys were examined by histology. Serum indexes of renal injury, inflammation and oxidative stress were detected by commercial kits. RNA sequencing (RNA-seq) was performed to screen potential pathways and the expressions of key molecules in these pathways were determined by western blotting and immunohistochemistry.

Results: Crystal deposition, tubular injury, fibrosis and increased ROS production in kidneys of mice induced by oxalate diet were improved with HRW administration. The indexes of renal injury, inflammation and oxidative stress in serum of mice were upregulated by oxalate diet, which were reduced by HRW. A total of 3,566 differential genes were screened by RNA-seq and these genes were analyzed by pathway enrichment and PI3K/AKT, NF-κB, and TGF-β pathways were selected for further verification. The expressions of molecules related to PI3K-AKT pathway (PI3K, AKT, and p-AKT), NF-κB pathway (NF-κB p65, p- NF-κB p65, NLRP3, and IL-1β) and TGF-β pathway (TGF-β, TGF-βRI, TGF-βRII, p-Smad2, and p-Smad3) in renal tissues were increased by oxalate diet, which were reduced by HRW administration.

Conclusion: HRW may alleviate oxalate-induced kidney injury with its anti-oxidative, anti-inflammatory and anti-fibrotic effects via inhibiting PI3K/AKT, NF-κB, and TGF-β pathways.

UPLC-Q-TOF/MS based fecal metabolomics reveals the potential anti-diabetic effect of Xiexin Decoction on T2DM rats

Xiexin Decoction (XXD), a traditional Chinese medicine prescription composed of Rhei rhizome (RR), Scutellaria radix (SR) and Coptidis rhizome (CR), has been used to cure diabetes in clinical practices for thousands of years, but its mechanism is not clear. Our previous study indicated that XXD could significantly ameliorate the symptom of type 2 diabetes mellitus (T2DM) rats by shifting the composition of gut microbiota. However, the effect of XXD on the metabolic activity of gut microbiota is not clarified. In this study, the underlying mechanism of XXD on the amelioration of T2DM was explored by fecal metabolic profiling analysis based on ultra performance liquid chromatography coupled with quadrupole time-of-fight mass spectrometry (UPLC-Q-TOF/MS). The disordered metabolic profiles in T2DM rats were notably improved by XXD. Ten potential biomarkers, which were mainly involved in arachidonic acid metabolism, amino acid metabolism, bile acid metabolism, glycolysis and gluconeogenesis, were identified. Furthermore, these metabolites were closely related to SCFAs-producing and anti-inflammatory gut microflora. After XXD intervention, these biomarkers restored to the normal level at some extent. This study not only revealed potential biomarkers and related pathways in T2DM rats affected by XXD, but also provided a novel insight to uncover how traditional herb medicines worked from fecal metabolomics.

Induced sputum metabolomic profiles and oxidative stress are associated with chronic obstructive pulmonary disease (COPD) severity: potential use for predictive, preventive, and personalized medicine

Chronic obstructive pulmonary disease (COPD) is a highly heterogeneous disease, and metabolomics plays a hub role in predictive, preventive, and personalized medicine (PPPM) related to COPD. This study thus aimed to reveal the role of induced sputum metabolomics in predicting COPD severity. In this pilot study, a total of 20 COPD patients were included. The induced sputum metabolites were assayed using a liquid chromatography-mass spectrometry (LC-MS/MS) system. Five oxidative stress products (myeloperoxidase (MPO), superoxide dismutase (SOD), glutathione (GSH), neutrophil elastase (NE), and 8-iso-PGF2α) in induced sputum were measured by ELISA, and the metabolomic profiles were distinguished by principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA). The Kyoto Encyclopedia of Genes and Genomes (KEGG) was used for pathway enrichment analysis, and a significant difference in induced sputum metabolomics was observed between moderate and severe COPD. The KEGG analysis revealed that the glycerophospholipid metabolism pathway was downregulated in severe COPD. Due to the critical role of glycerophospholipid metabolism in oxidative stress, significant negative correlations were discovered between glycerophospholipid metabolites and three oxidative stress products (SOD, MPO, and 8-iso-PGF2α). The diagnostic values of SOD, MPO, and 8-iso-PGF2α in induced sputum were found to exhibit high sensitivities and specificities in the prediction of COPD severity. Collectively, this study provides the first identification of the association between induced sputum metabolomic profiles and COPD severity, indicating the potential value of metabolomics in PPPM for COPD management. The study also reveals the correlation between glycerophospholipid metabolites and oxidative stress products and their value for predicting COPD severity.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-020-00227-w.

Metabolomics study of fasudil on cisplatin-induced kidney injury

Fasudil is a derivative of 5-isoquinoline sulfonamide, which is a Rho kinase inhibitor, a wide range of pharmacological effects. Fasudil has been shown to attenuate kidney injury caused by certain substances. In the present study, metabolomic analysis of mouse kidney tissues ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry was used to determine the metabolomic changes in cisplatin-induced kidney injury and the fasudil-induced attenuation of cisplatin-induced kidney injury. Metabolomic profiling of kidney tissues revealed significant differences in metabolites between the control group and the cisplatin group and between the cisplatin group and the fasudil-intervention group. With metabolomic approach, 68 endogenous differential metabolites were found, and multivariate statistical analysis, accurate molecular weights, isotope tracers, mass-spectrometry secondary-fragment information, and standard-reference comparisons were used to identify these substances. Based on these differential metabolites, a metabolic-pathway network was constructed and revealed that fasudil primarily attenuated cisplatin-induced renal injury by modulating lipid and amino-acid metabolism. These results further demonstrate that kidney injury can be induced by cisplatin and, moreover, suggest that fasudil can be used to reduce kidney injury at early stages in patients treated with cisplatin.

Hydrogen protects against chronic intermittent hypoxia induced renal dysfunction by promoting autophagy and alleviating apoptosis

AIMS

Hydrogen gas (H₂) has a diversity of effects such as anti-apoptotic, anti-inflammatory and anti-oxidative properties. However, molecular mechanism underlying the potential effect of H₂ on chronic intermittent hypoxia (CIH) induced renal injury remains obscure.

MATERIALS AND METHODS

In the present study, adult male Sprague-Dawley rats were randomly allocated into four groups: control (CON) group, CIH group, CIH with H₂ treatment (CIH + H₂) group, and control with H₂ treatment (CON + H₂) group. Oxidative stress, autophagy and endoplasmic reticulum (ER) stress were detected to determine how H₂ affected the renal function of CIH exposed rats.

KEY FINDINGS

We demonstrated that rats who inhale hydrogen gas showed improved renal function, alleviated pathological damage, oxidative stress and apoptosis in CIH rats. Meanwhile, CIH-induced endoplasmic reticulum stress was decreased by H₂ as the expressions of CHOP, caspase-12, and GRP78 were down-regulated. Furthermore, relative higher levels of LC3-II/I ratio and Beclin-1, with decreased expression of p62, were found after H₂ administrated. Inhibition of mTOR may be involved in the upregulation of autophagy by H₂. Finally, increased phosphorylation of p38 and JNK was involved in the CIH-induced pathological process. H₂ could inhibit the activation of p38 and JNK, suggesting H₂ played an active part in resisting renal injury via MAPK.

SIGNIFICANCE

Taken together, our study reveals that H₂ can ameliorate CIH-induced kidney injury by decreasing endoplasmic reticulum stress and activating autophagy through inhibiting oxidative stress-dependent p38 and JNK MAPK activation.

Metabolomics biotechnology, applications, and future trends: a systematic review

Given the highly increased incidence of human diseases, a better understanding of the related mechanisms regarding endogenous metabolism is urgently needed. Mass spectrometry-based metabolomics has been used in a variety of disease research areas. However, the deep research of metabolites remains a difficult and lengthy process. Fortunately, mass spectrometry is considered to be a universal tool with high specificity and sensitivity and is widely used around the world. Mass spectrometry technology has been applied to various basic disciplines, providing technical support for the discovery and identification of endogenous substances in living organisms. The combination of metabolomics and mass spectrometry is of great significance for the discovery and identification of metabolite biomarkers. The mass spectrometry tool could further improve and develop the exploratory research of the life sciences. This mini review discusses metabolomics biotechnology with a focus on recent applications of metabolomics as a powerful tool to elucidate metabolic disturbances and the related mechanisms of diseases.

Given the highly increased incidence of human diseases, a better understanding of the related mechanisms regarding endogenous metabolism is urgently needed.