Proteomic Identification of Nrf2-Mediated Phase II Enzymes Critical for Protection of Tao Hong Si Wu Decoction against Oxygen Glucose Deprivation Injury in PC12 Cells

Protection of Taohong Siwu Decoction on PC12 cells injured by oxygen glucose deprivation/reperfusion via mitophagy-NLRP3 inflammasome pathway in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Taohong Siwu Decoction (THSWD) is a traditional Chinese medicine formula used to invigorate blood circulation and resolve blood stasis. It consists of Paeonia lactiflora Pall., Conioselinum anthriscoides (H.Boissieu) Pimenov & Kljuykov, Rehmannia glutinosa (Gaertn.) DC., Prunus persica (L.) Batsch, Angelica sinensis (Oliv.) Diels, and Carthamus creticus L. in the ratio of 3:2:4:3:3:2. THSWD is a common prescription for the treatment of ischemic stroke.

AIM OF THE STUDY

To study the protective effect and mechanism of Taohong Siwu Decoction (THSWD) on PC12 cells damaged by oxygen glucose deprivation/reperfusion (OGD/R).

MATERIALS AND METHODS

OGD/R model of PC12 cells was used to simulate ischemia-reperfusion (I/R) injury of nerve cells in vitro. The experiment was grouped as follows: control, OGD/R and OGD/R + THSWD (5%, 10% and 15%) group. Oxygen and glucose was restored for 24 h after 4-6 h of deprivation. The severity of damage to PC12 cells was evaluated by CCK8, flow cytometry and lactate dehydrogenase (LDH). Mitochondrial morphology and function were examined by transmission electron microscopy (TEM), ATP and mitochondrial membrane potential (MMP) assay kits. Cellular autophagy and NLRP3 inflammasome-associated proteins were detected by Western blot and immunofluorescence staining.

RESULTS

THSWD treatment improved the survival rate of PC12 cells injured by OGD/R, reduced cell damage and apoptosis. Moreover, ATP, MMP and the expression of autophagy marker proteins (LC3-II/LC3-I, Beclin1, Atg5) and mitophagy marker proteins (Parkin and PINK-1) was significantly elevated. The reactive oxygen species (ROS), NLRP3 inflammasome and pro-inflammatory cytokines induced by OGD/R were distinctly reduced. In contrast, these above beneficial effects of THSWD on mitochondrial autophagy and NLRP3 inflammasome were reversed by mitochondrial division inhibitory factor 1 (Mdivi-1).

CONCLUSION

THSWD protects PC12 cells against OGD/R injury by heightening mitophagy and suppressing the activation of NLRP3 inflammasome.

Proteomic Analysis Reveals that Di Dang Decoction Protects Against Acute Intracerebral Hemorrhage Stroke in Rats by Regulating S100a8, S100a9 Col1a1, and Col1a2

OBJECTIVE

The present study aimed to explore the neuroprotective mechanism of Di Dang decoction (DDD) during acute intracerebral hemorrhage (AICH) stroke in Sprague Dawley rats through proteomic analysis.

METHODS

A total of 135 healthy Sprague Dawley rats were randomly divided into five groups: control (n = 27), model (n = 27), DDD low-dose (n = 27), DDD medium-dose (n = 27), and DDD high-dose (n = 27). AICH stroke in rats was induced by injecting autologous blood into the caudate nucleus. The modified Neurological Severity Score (mNSS) was used to evaluate the cerebral nerve function deficit. Hematoxylin and eosin (HE) staining was performed to observe the brain tissue at the lesion site. Albumin concentration was assessed on obvious blood-brain barrier damaged and brain water content was used to evaluate the brain injury. For quantitative proteomics, proteins were extracted from the cerebral cortices. Target proteins were identified using mass spectrometer-based targeted proteomic quantification.

RESULTS

mNSS score, HE staining results, albumin concentration, and brain water content showed the most significant improvements in the neuroprotective in the high-dose group 7 days after DDD exposure. Furthermore, quantitative proteomics analysis showed that, relative to the control group, S100a8 and S100a9 were downregulated by 0.614 (p = 0.033702) and 0.506 times (p = 0.000024) in the high-dose group. Compared with the control group, Col1a1 and Col1a2 were upregulated by 1.319 (p = 0.000184) and 1.348 (p = 0.014097) times in the high-dose group. These results were confirmed using mass spectrometer-based targeted proteomic quantification.

CONCLUSION

Application of a high-dose DDD for 7 days in AICH stroke rats showed the most significant improvements in neuroprotective. Mechanistically, this effect was mediated by S100a8 and S100a9 protein downregulation and Col1a1 and Col1a2 upregulation.

Quantitative Proteomics Reveals the Beneficial Effects of Low Glucose on Neuronal Cell Survival in an in vitro Ischemic Penumbral Model

Understanding proteomic changes in the ischemic penumbra are crucial to rescue those salvageable cells and reduce the damage of an ischemic stroke. Since the penumbra region is dynamic with heterogeneous cells/tissues, tissue sampling from animal models of stroke for the molecular study is a challenge. In this study, cultured hippocampal HT22 cells under hypoxia treatment for 17.5 h with 0.69 mM low glucose (H+LG) could mimic ischemic penumbral cells since they had much higher cell viability and viable cell number compared to hypoxia without glucose (H-G) treatment. To validate established cell-based ischemic penumbral model and understand the beneficial effects of low glucose (LG), quantitative proteomics analysis was performed on H+LG, H-G, and normoxia with normal 22 mM glucose (N+G) treated cells. We identified 427 differentially abundant proteins (DAPs) between H-G and N+G and further identified 105 DAPs between H+LG and H-G. Analysis of 105 DAPs revealed that LG promotes cell survival by activating HIF1α to enhance glycolysis; preventing the dysregulations of extracellular matrix remodeling, cell cycle and division, and antioxidant and detoxification; as well as attenuating inflammatory reaction response, protein synthesis and neurotransmission activity. Our results demonstrated that this established cell-based system could mimic penumbral conditions and can be used for molecular studies.

Sulforaphane Attenuates H₂O₂-induced Oxidant Stress in Human Trabecular Meshwork Cells (HTMCs) via the Phosphatidylinositol 3-Kinase (PI3K)/Serine/Threonine Kinase (Akt)-Mediated Factor-E2-Related Factor 2 (Nrf2) Signaling Activation

Background

The aim of this study was to investigate whether and how sulforaphane (SFN), a novel promising nuclear factor-E2-related factor 2 (Nrf2) activator, exerted antioxidative stress through activating Nrf2 signaling.

Material/Methods

Cultured human trabecular meshwork cells (HTMCs) were treated with SFN for 6 hours after establishing the oxidative stress model by hydrogen peroxide (H₂O₂). The cell viability, the level of intercellular reactive oxygen species (ROS), and the apoptosis rate were observed using various kits. In addition, the gene and protein expression of Nrf2 and the phase II antioxidative enzymes were determined by performing qRT-PCR and western blotting.

Results

In H₂O₂-treated HTMCs, SFN protected HTMCs from oxidative stress damage and decreased the intracellular ROS accumulation, thus inhibiting cell apoptosis. SFN also increased the gene and protein expression of phase II antioxidative enzymes such as NAD(P)H: quinone oxidoreductase 1 (NQO-1), heme oxygenase-1 (HO-1), glutamate-cysteine ligase catalytic subunit (GCLC), and glutamate-cysteine ligase modifier subunit (GCLM) by Nrf2-dependent pathway. Furthermore, investigations of the pathway showed that HTMCs pretreated with LY294002, an inhibitor of phosphatidylinositol 3-kinase (PI3K), downregulated the expression of phase II antioxidative enzymes, partly.

Conclusions

These results indicated a novel application for SFN in attenuating H₂O₂-induced oxidative stress in HTMCs through activating PI3K/Akt/Nrf2 signaling pathway.

Differential proteomics for studying action mechanisms of traditional Chinese medicines

Differential proteomics, which has been widely used in studying of traditional Chinese medicines (TCMs) during the past 10 years, is a powerful tool to visualize differentially expressed proteins and analyzes their functions. In this paper, the applications of differential proteomics in exploring the action mechanisms of TCMs on various diseases including cancers, cardiovascular diseases, diabetes, liver diseases, kidney disorders and obesity, etc. were reviewed. Furthermore, differential proteomics in studying of TCMs identification, toxicity, processing and compatibility mechanisms were also included. This review will provide information for the further applications of differential proteomics in TCMs studies.

Systems biology approaches in the study of Chinese herbal formulae

Systems biology is an academic field that attempts to integrate different levels of information to understand how biological systems function. It is the study of the composition of all components of a biological system and their interactions under specific conditions. The core of systems biology is holistic and systematic research, which is different from the manner of thinking and research of all other branches of biology to date. Chinese herbal formulae (CHF) are the main form of Chinese medicine and are composed of single Chinese herbal medicines (CHMs) with pharmacological and pharmacodynamic compatibility. When single CHMs are combined into CHF, the result is different from the original effect of a single drug and can be better adapted to more diseases with complex symptoms. CHF represent a complex system with multiple components, targets and effects. Therefore, the use of systems biology is conducive to revealing the complex characteristics of CHF. With the rapid development of omics technologies, systems biology has been widely and increasingly applied to the study of the basis of the pharmacological substances, action targets and mechanisms of CHF. To meet the challenges of multiomics synthesis-intensive studies and system dynamics research in CHF, this paper reviews the common techniques of genomics, transcriptomics, proteomics, metabolomics, and metagenomics and their applications in research on CHF.

DiDang Tang Inhibits Endoplasmic Reticulum Stress-Mediated Apoptosis Induced by Oxygen Glucose Deprivation and Intracerebral Hemorrhage Through Blockade of the GRP78-IRE1/PERK Pathways

DiDang Tang (DDT), a Chinese traditional medicine formula, contains 4 Chinese traditional medicine substances, has been widely used to treat intracerebral hemorrhage (ICH) patients. However, the molecular mechanisms of DDT for protecting neurons from oxygen and glucose deprivation (OGD)-induced endoplasmic reticulum (ER) stress and apoptosis after ICH still remains elusive. In this study, high-performance liquid chromatography fingerprint analysis was performed to learn the features of the chemical compositions of DDT. OGD-induced ER stress, Ca²⁺ overload, and mitochondrial apoptosis were investigated in nerve growth factor -induced PC12, primary neuronal cells, and ICH rats to evaluate the protective effect of DDT. We found that DDT treatment protected neurons against OGD-induced damage and apoptosis by increasing cell viability and reducing the release of lactate dehydrogenase. DDT decreased OGD-induced Ca²⁺ overload and ER stress through the blockade of the glucose-regulated protein 78 (GRP78)- inositol-requiring protein 1α (IRE1)/ protein kinase RNA-like ER kinase (PERK) pathways and also inhibited apoptosis by decreasing mitochondrial damage. Moreover, we observed similar findings when we studied DDT for inhibition of ER stress in a rat model of ICH. In addition, our experiments further confirmed the neuroprotective potential of DDT against tunicamycin (TM)-induced neural damage. Our in vitro and in vivo results indicated that the neuroprotective effect of DDT against ER stress damage and apoptosis occurred mainly by blocking the GPR78-IRE1/PERK pathways. Taken together, it provides reliable experimental evidence and explains the molecular mechanism of DDT for the treatment of patients with ICH.

The Use of Omic Technologies Applied to Traditional Chinese Medicine Research

Natural products represent one of the most important reservoirs of structural and chemical diversity for the generation of leads in the drug development process. A growing number of researchers have shown interest in the development of drugs based on Chinese herbs. In this review, the use and potential of omic technologies as powerful tools in the modernization of traditional Chinese medicine are discussed. The analytical combination from each omic approach is crucial for understanding the working mechanisms of cells, tissues, organs, and organisms as well as the mechanisms of disease. Gradually, omic approaches have been introduced in every stage of the drug development process to generate high-quality Chinese medicine-based drugs. Finally, the future picture of the use of omic technologies is a promising tool and arena for further improvement in the modernization of traditional Chinese medicine.

Pretreatment with baicalin attenuates hypoxia and glucose deprivation-induced injury in SH-SY5Y cells

OBJECTIVE

To explore the neuroprotective effects of baicalin against hypoxia and glucose deprivation-reperfusion (OGD/RO)-induced injury in SH-SY5Y cells.

METHODS

SH-SY5Y cells were divided into a control group, a OGD/RO group, which was subject to OGD/RO induction; and 3 baicalin groups subject to baicalin (1, 5, 25 μmol/L) for 2 h before induction of OGD/RO (low-, medium-, and high-dose baicalin groups). Cell viability was detected by thiazolyl blue tetrazolium bromide (MTT) assay and flow cytometric analysis was used to detect cell apoptosis. Real-time polymerase chain reaction was performed to determine the mRNA expression of caspase-3 gene. Western blot analysis was conducted to determine the expression of nuclear factor (NF)-κB and N-methyl-daspartic acid receptor-1 (NMDAR1).

RESULTS

Baicalin could significantly attenuate OGD/RO mediated apoptotic cell death in SH-SY5Y cells; the apoptosis rates in the low-, medium- and high-dose groups were 12.1%, 7.9%, and 5.4%, respectively. Western blot and real-time PCR analysis revealed that significant decrease in caspase-3 expression in the baicalin group compared with the OGD/RO group (P<0.01). Additionally, down-regulation of NF-κB and NMDAR1 was observed in the baicalin group compared with those obtained from the OGD/RO group. Compared with the low-dose baicalin group, remarkable decrease was noted in the medium- and high-dose groups (P<0.01).

CONCLUSION

Baicalin pre-treatment attenuates brain ischemia reperfusion injury by suppressing cellular apoptosis.

Baicalin protects against thrombin induced cell injury in SH-SY5Y cells

Baicalin, an extract from the dried root of Scutellaria baicalensis Georgi, was shown to be neuroprotective. However, the precise mechanisms are incompletely known. In this study, we determined the effect of baicalin on thrombin induced cell injury in SH-SY5Y cells, and explored the possible mechanisms. SH-SY5Y cells was treated with thrombin alone or pre-treated with baicalin (5, 10, 20 μM) for 2 h followed by thrombin treatment. Cells without thrombin and baicalin treatment were used as controls. Cell viability was detected by MTT assay. Cell apoptosis was analyzed by flow cytometry. Real-time PCR was performed to determine the mRNA expression of protease-activated receptor-1 (PAR-1). Western blotting was conducted to determine the protein expression of PAR-1, Caspase-3 and NF-κB. Baicalin reduced cell death following thrombin treatment in a dose-dependent manner, with concomitant inhibition of NF-κB activation and suppression of PAR-1 expression. In addition, baicalin reduced Caspase-3 expression. The above findings indicated that baicalin prevents against cell injury after thrombin stimulation possibly through inhibition of PAR-1 expression and NF-κB activation.

Recent Advance in Applications of Proteomics Technologies on Traditional Chinese Medicine Research

Proteomics technology, a major component of system biology, has gained comprehensive attention in the area of medical diagnosis, drug development, and mechanism research. On the holistic and systemic theory, proteomics has a convergence with traditional Chinese medicine (TCM). In this review, we discussed the applications of proteomic technologies in diseases-TCM syndrome combination researches. We also introduced the proteomic studies on the in vivo and in vitro effects and underlying mechanisms of TCM treatments using Chinese herbal medicine (CHM), Chinese herbal formula (CHF), and acupuncture. Furthermore, the combined studies of proteomics with other “-omics” technologies in TCM were also discussed. In summary, this report presents an overview of the recent advances in the application of proteomic technologies in TCM studies and sheds a light on the future global and further research on TCM.