Tanshinone IIA Ameliorates Spatial Learning and Memory Deficits by Inhibiting the Activity of ERK and GSK-3β

Therapeutic effects of Tanshinone IIA and Tetramethylpyrazine nanoemulsions on cognitive impairment and neuronal damage in Alzheimer's disease rat models

OBJECTIVES

The aim of this study was to investigate the therapeutic effects and related mechanisms of Tanshinone IIA and Tetramethylpyrazine O/W composite nanoemulsions on Alzheimer's disease (AD) rats.

METHODS

The therapeutic effect of TSN/TMP O/W NEs on AD rats was evaluated by behavioral tests, H&E, Nissl, and Immunohistochemistry staining. ELISA and Western blot were used to analyze the mechanism.

KEY FINDINGS

The results showed that TSN/TMP O/W NEs could down-regulate the expression of Bax and Caspase-3 proteins, decrease the level of MDA, increase the expression of SOD and GSH-Px, and alleviate cognitive impairment in AD rats.

CONCLUSIONS

TSN/TMP O/W NEs can inhibit MAPK/ERK/CREB signaling pathway and effectively alleviate cognitive impairment, oxidative stress injury, and neuronal apoptosis in AD rats.

Mechanism of Salvia miltiorrhiza Bunge extract to alleviate Chronic Sleep Deprivation-Induced cognitive dysfunction in rats

BACKGROUND

Bidirectional communication between the gut microbiota and the brain may play an essential role in the cognitive dysfunction associated with chronic sleep deprivation(CSD). Salvia miltiorrhiza Bunge (Danshen, DS), a famous Chinese medicine and functional tea, is extensively used to protect learning and memory capacities, although the mechanism of action remains unknown.

PURPOSE

The purpose of this research was to explore the efficacy and the underlying mechanism of DS in cognitive dysfunction caused by CSD.

METHODS

DS chemical composition was analyzed by UPLC-QTOF-MS/MS. Forty rats were randomly assigned to five groups (n = 8): control (CON), model (MOD), low- (1.35 g/kg, DSL), high-dose (2.70 g/kg, DSH) DS group, and Melatonin(100 mg/kg, MT) group. A CSD rat model was established over 21 days. DS's effects and the underlying mechanism were explored using the open-field test(OFT), Morris water-maze(MWM), tissue staining(Hematoxylin and Eosin Staining, Nissl staining, Alcian blue-periodic acid SCHIFF staining, and Immunofluorescence), enzyme-linked immunosorbent assay, Western blot, quantitative real-time polymerase chain reaction(qPCR), and 16S rRNA sequencing.

RESULTS

We demonstrated that CSD caused gut dysbiosis and cognitive dysfunction. Furthermore, 16S rRNA sequencing demonstrated that Firmicutes and Proteobacteria were more in fecal samples from model group rats, whereas Bacteroidota and Spirochaetota were less. DS therapy, on the contrary hand, greatly restored the gut microbial community, consequently alleviating cognitive impairment in rats. Further research revealed that DS administration reduced systemic inflammation via lowering intestinal inflammation and barrier disruption. Following that, DS therapy reduced Blood Brain Barrier(BBB) and neuronal damage, further decreasing neuroinflammation in the hippocampus(HP). Mechanistic studies revealed that DS therapy lowered lipopolysaccharide (LPS) levels in the HP, serum, and colon, consequently blocking the TLR4/MyD88/NF-κB signaling pathway and its downstream pro-inflammatory products(IL-1β, IL-6, TNF-α, iNOS, and COX2) in the HP and colon.

CONCLUSION

DS treatment dramatically improved spatial learning and memory impairments in rats with CSD by regulating the composition of the intestinal flora, preserving gut and brain barrier function, and reducing inflammation mediated by the LPS-TLR4 signaling pathway. Our findings provide novel insight into the mechanisms by which DS treats cognitive dysfunction caused by CSD.

Altered synaptic currents, mitophagy, mitochondrial dynamics in Alzheimer's disease models and therapeutic potential of Dengzhan Shengmai capsules intervention

Emerging research suggests a potential association of progression of Alzheimer's disease (AD) with alterations in synaptic currents and mitochondrial dynamics. However, the specific associations between these pathological changes remain unclear. In this study, we utilized Aβ42-induced AD rats and primary neural cells as in vivo and in vitro models. The investigations included behavioural tests, brain magnetic resonance imaging (MRI), liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis, Nissl staining, thioflavin-S staining, enzyme-linked immunosorbent assay, Golgi-Cox staining, transmission electron microscopy (TEM), immunofluorescence staining, proteomics, adenosine triphosphate (ATP) detection, mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) assessment, mitochondrial morphology analysis, electrophysiological studies, Western blotting, and molecular docking. The results revealed changes in synaptic currents, mitophagy, and mitochondrial dynamics in the AD models. Remarkably, intervention with Dengzhan Shengmai (DZSM) capsules emerged as a pivotal element in this investigation. Aβ42-induced synaptic dysfunction was significantly mitigated by DZSM intervention, which notably amplified the frequency and amplitude of synaptic transmission. The cognitive impairment observed in AD rats was ameliorated and accompanied by robust protection against structural damage in key brain regions, including the hippocampal CA3, primary cingular cortex, prelimbic system, and dysgranular insular cortex. DZSM intervention led to increased IDE levels, augmented long-term potential (LTP) amplitude, and enhanced dendritic spine density and length. Moreover, DZSM intervention led to favourable changes in mitochondrial parameters, including ROS expression, MMP and ATP contents, and mitochondrial morphology. In conclusion, our findings delved into the realm of altered synaptic currents, mitophagy, and mitochondrial dynamics in AD, concurrently highlighting the therapeutic potential of DZSM intervention.

Research Progress on Natural Plant Molecules in Regulating the Blood-Brain Barrier in Alzheimer's Disease

Alzheimer's disease (AD) is a prevalent neurodegenerative disorder. With the aging population and the continuous development of risk factors associated with AD, it will impose a significant burden on individuals, families, and society. Currently, commonly used therapeutic drugs such as Cholinesterase inhibitors, N-methyl-D-aspartate antagonists, and multiple AD pathology removal drugs have been shown to have beneficial effects on certain pathological conditions of AD. However, their clinical efficacy is minimal and they are associated with certain adverse reactions. Furthermore, the underlying pathological mechanism of AD remains unclear, posing a challenge for drug development. In contrast, natural plant molecules, widely available, offer multiple targeting pathways and demonstrate inherent advantages in modifying the typical pathologic features of AD by influencing the blood-brain barrier (BBB). We provide a comprehensive review of recent in vivo and in vitro studies on natural plant molecules that impact the BBB in the treatment of AD. Additionally, we analyze their specific mechanisms to offer novel insights for the development of safe and effective targeted drugs as well as guidance for experimental research and the clinical application of drugs for the prevention and treatment of AD.

The Role of Traditional Chinese Medicine Natural Products in β-Amyloid Deposition and Tau Protein Hyperphosphorylation in Alzheimer's Disease

Alzheimer's disease is a prevalent form of dementia among elderly individuals and is characterized by irreversible neurodegeneration. Despite extensive research, the exact causes of this complex disease remain unclear. Currently available drugs for Alzheimer's disease treatment are limited in their effectiveness, often targeting a single aspect of the disease and causing significant adverse effects. Moreover, these medications are expensive, placing a heavy burden on patients' families and society as a whole. Natural compounds and extracts offer several advantages, including the ability to target multiple pathways and exhibit high efficiency with minimal toxicity. These attributes make them promising candidates for the prevention and treatment of Alzheimer's disease. In this paper, we provide a summary of the common natural products used in Chinese medicine for different pathogeneses of AD. Our aim is to offer new insights and ideas for the further development of natural products in Chinese medicine and the treatment of AD.

Effects and mechanisms of tanshinone IIA on PTSD-like symptoms

BACKGROUND

In recent years, Salvia miltiorrhiza and its active substances have remarkably progressed in treating central neurological disorders. Tanshinone IIA (TSA) is an active ingredient derived from the rhizome of Salvia miltiorrhiza that has been found to alleviate the symptoms of several psychiatric illnesses. Post-traumatic stress disorder (PTSD) is a mental disorder that results after experiencing a serious physical or psychological injury. The currently used drugs are not satisfactory for the treatment of PTSD. However, it has been reported that TSA can improve PTSD-like symptoms like learning and memory, cognitive disorder, and depression through multi-target regulation.

PURPOSE

This paper discusses the ameliorative effects of TSA on PTSD-like symptoms and the possible mechanisms of action in terms of inhibition of neuronal apoptosis, anti-neuroinflammation, and anti-oxidative stress. Based on the pathological changes and clinical observations of PTSD, we hope to provide some reference for the clinical transformation of Chinese medicine in treating PTSD.

METHODS

A large number of literatures on tanshinone in the treatment of neurological diseases and PTSD were retrieved from online electronic PubMed and Web of Science databases.

CONCLUSION

TSA is a widely studied natural active ingredient against mental illness. This review will contribute to the future development of TSA as a new clinical candidate drug for improving PTSD-like symptoms.

Therapeutic prospects of naturally occurring p38 MAPK inhibitors tanshinone IIA and pinocembrin for the treatment of SARS-CoV-2-induced CNS complications

P38 mitogen-activated protein kinase (p38 MAPK) signaling pathway is closely related to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) replication and hyperinflammatory responses in coronavirus disease 2019 (COVID-19). Therefore, blood-brain barrier-penetrating p38 MAPK inhibitors have good potential for the treatment of central nervous system (CNS) complications of COVID-19. The aim of the present study is the characterization of the therapeutic potential of tanshinone IIA and pinocembrin for the treatment of CNS complications of COVID-19. Studies published in high-quality journals indexed in databases Scopus, Web of Science, PubMed, and so forth were used to review the therapeutic capabilities of selected compounds. In continuation of our previous efforts to identify agents with favorable activity/toxicity profiles for the treatment of COVID-19, tanshinone IIA and pinocembrin were identified with a high ability to penetrate the CNS. Considering the nature of the study, no specific time frame was determined for the selection of studies, but the focus was strongly on studies published after the emergence of COVID-19. By describing the association of COVID-19-induced CNS disorders with p38 MAPK pathway disruption, this study concludes that tanshinone IIA and pinocembrin have great potential for better treatment of these complications. The inclusion of these compounds in the drug regimen of COVID-19 patients requires confirmation of their effectiveness through the conduction of high-quality clinical trials.

Tanshinone IIA changed the amniotic fluid volume and regulated expression of AQP1 and AQP3 in amniotic epithelium cells: a promising drug treating abnormal amniotic fluid volume

BACKGROUND

Many studies have confirmed the association of aquaporins (AQPs) with abnormal amniotic fluid volume (AFV). In our previous experiments, we found that Tanshinone IIA was able to regulate the expression of AQP1 and AQP3. However, the exact mechanism by which Tanshinone IIA regulates AQPs protein expression and its effect on AFV remains unclear. The purpose of this study was to investigate the effects of Tanshinone IIA on AFV and the possible molecular mechanism of regulation of AQP1 and AQP3.

METHODS

The expression of AQPs protein in the amniotic membranes was compared between pregnant women with normal pregnancy and those with isolated oligohydramnios. The AQP1 knockout (AQP1-KO) mice and wild-type (WT) mice were treated with saline or Tanshinone IIA (10 mg/kg) at 13.5GD and 16.5GD. Human amniotic epithelium cells (hAECs) from pregnant women with normal AFV and isolated oligohydramnios were incubated with 35 μmmol/L Tanshinone IIA or 25 mmol/L LiCl [inhibitor of glycogen synthetic kinase 3β (GSK-3β)]. The protein expressions of AQPs, GSK-3β, phospho-GSK-3β (Ser9) in fetal membranes of mice and human amniotic epithelium cells were detected by western blotting.

RESULTS

The expression of AQP1 protein in the amniotic membrane of isolated oligohydramnios was increased compared with normal pregnancy. The AFV in AQP1-KO mice is higher than that in WT mice. In wild-type mice, AFV in Tanshinone IIA group was significantly higher than that in control group, and AQP1 protein expression was significantly lower than that in control group, but in AQP1 knockout mice, Tanshinone IIA reduced amniotic fluid volume and AQP3 protein expression at 16.5GD. Tanshinone IIA reduced AQP1, AQP3 and p-GSK-3β (Ser9) protein expression in normal hAECs, and this effect was inhibited by LiCl. In hAECs with oligohydramnios, the down-regulation of AQP1 and up-regulation of AQP3 by Tanshinone IIA was independent of GSK-3β signaling pathway.

CONCLUSIONS

Tanshinone IIA may increase AFV in normal pregnancy by downregulating AQP1 protein expression in the fetal membranes, which may be associated with p-GSK-3β signaling pathway. But a larger AFV in AQP1-KO mice was significantly attenuated by Tanshinone IIA, which may be related to AQP3. Tanshinone IIA is a promising drug for the treatment of amniotic fluid abnormality.

The Interplay Between Cholesterol and Amyloid-β on HT22 Cell Viability, Morphology, and Receptor Tyrosine Kinase Signaling

BACKGROUND

There is a lack of understanding in the molecular and cellular mechanisms of Alzheimer's disease that has hindered progress on therapeutic development. The focus has been on targeting toxic amyloid-β (Aβ) pathology, but these therapeutics have generally failed in clinical trials. Aβ is an aggregation-prone protein that has been shown to disrupt cell membrane structure in molecular biophysics studies and interfere with membrane receptor signaling in cell and animal studies. Whether the lipid membrane or specific receptors are the primary target of attack has not been determined.

OBJECTIVE

This work elucidates some of the interplay between membrane cholesterol and Aβ42 on HT22 neuronal cell viability, morphology, and platelet-derived growth factor (PDGF) signaling pathways.

METHODS

The effects of cholesterol depletion by methyl-β-cyclodextrin followed by treatment with Aβ and/or PDGF-AA were assessed by MTT cell viability assays, western blot, optical and AFM microscopy.

RESULTS

Cell viability studies show that cholesterol depletion was mildly protective against Aβ toxicity. Together cholesterol reduction and Aβ42 treatment compounded the disruption of the PDGFα receptor activation. Phase contrast optical microscopy and live cell atomic force microscopy imaging revealed that cytotoxic levels of Aβ42 caused morphological changes including cell membrane damage, cytoskeletal disruption, and impaired cell adhesion; cell damage was ameliorated by cellular cholesterol depletion.

CONCLUSIONS

Cholesterol depletion impacted the effects of Aβ42 on HT22 cell viability, morphology, and receptor tyrosine kinase signaling.

Tanshinone IIA loaded chitosan nanoparticles decrease toxicity of β-amyloid peptide in a Caenorhabditis elegans model of Alzheimer's disease

Alzheimer's disease (AD) is one of the most common neurodegenerative diseases that characterized by the accumulation of β-amyloid peptide (Aβ). Overexpressions of Aβ could induce oxidative stress that might be a key insult to initiate the cascades of Aβ accumulation. As a result, anti-oxidative stress and attenuating Aβ accumulation might be one promising intervention for AD treatment. Tanshinone IIA (Tan IIA), a major component of lipophilic tanshinones in Danshen, is proven to be effective in several diseases, including AD. Due to the poor solubility in water, the clinical application of Tan IIA was limited. Therefore, a great number of nanoparticles were designed to overcome this issue. In the current study, we choose chitson as delivery carrier to load Tanshinone IIA (CS@Tan IIA) and explore the protective effects of CS@Tan IIA on the CL2006 strain, a transgenic C. elegans of AD model organism. Compared with Tan IIA monomer, CS@Tan IIA could significantly prolong the lifespan and attenuate the AD-like symptoms, including reducing paralysis and the Aβ deposition by inhibiting the oxidative stress. The mechanism study showed that the protection of CS@Tan IIA was attenuated by knockdown of daf-16 gene, but not skn-1. The results indicated that DAF-16/SOD-3 pathway was required in the protective effects of CS@Tan IIA. Besides DAF-16/SOD-3 pathway, the Tan IIA-loaded CS nanoparticles might protect the C. elegans against the AD insults via promoting autophagy. All the results consistently suggested that coating by chitosan could improve the solubility of Tan IIA and effectively enhance the protective effects of Tan IIA on AD, which might provide a potential drug loading approach for the hydrophobic drugs as Tan IIA.

Tanshinone IIA ameliorates chronic unpredictable mild stress-induced depression-like behavior and cognitive impairment in rats through the BDNF/TrkB/GAT1 signaling pathway

BACKGROUND

Depression is a common disorder with a complex pathogenesis. Tanshinone IIA (TAN IIA) is a botanical agent with neuroprotective and antidepressant properties.

OBJECTIVE

To examine the effects of TAN IIA on chronic unpredictable mild stress (CUMS)-induced depression-like behavior and cognitive impairment in rats.

METHODS

Rats were exposed to CUMS for 4 weeks, followed by the oral administration of TAN IIA, Deanxit (DEAN), or normal saline for an additional 4 weeks. The control rats were fed with regular chow and administered with normal saline for 4 weeks. Behavioral tests were performed to assess the effects of TAN IIA on depression-like behavior and cognitive impairment in rats with CUMS. The morphology of dendrites was analyzed by Golgi staining. Immunofluorescence staining was performed to determine protein localization.

RESULTS

TAN IIA treatment ameliorated CUMS-induced depression-like behavior and cognitive impairment in rats. TAN IIA treatment also reversed the effects of CUMS on dendritic complexity and the levels of gamma-aminobutyric acid (GABA) in the hippocampus and prefrontal cortex. Rats with CUMS showed decreased levels of brain-derived neurotrophic factor (BDNF) and phosphorylated tropomyosin receptor kinase B (TrkB), upregulated expression of GABA transporter 1 (GAT1), and reduced expression of synaptic proteins in the hippocampus, while TAN IIA treatment significantly diminished the effects of CUMS exposure. In addition, GAT1 was colocalized with N-methyl-D-aspartate receptor 2B.

CONCLUSION

TAN IIA ameliorates CUMS-induced depression-like behavior and cognitive impairment in rats by regulating the BDNF/TrkB/GAT1 signaling pathway, suggesting that TAN IIA may be a candidate drug for the treatment of depression.

Combination of indirect revascularization and endothelial progenitor cell transplantation improved cerebral perfusion and ameliorated tauopathy in a rat model of bilateral ICA ligation

Objective

Endothelial progenitor cells (EPCs) contribute to the recovery of neurological function after ischemic stroke. Indirect revascularization has exhibited promising effects in the treatment of cerebral ischemia related to moyamoya disease and intracranial atherosclerotic disease. The role of EPCs in augmenting the revascularization effect is not clear. In this study, we investigated the therapeutic effects of indirect revascularization combined with EPC transplantation in rats with chronic cerebral ischemia.

Methods

Chronic cerebral ischemia was induced by bilateral internal carotid artery ligation (BICAL) in rats, and indirect revascularization by encephalo-myo-synangiosis (EMS) was performed 1 week later. During the EMS procedure, intramuscular injection of EPCs and the addition of stromal cell-derived factor 1 (SDF-1), and AMD3100, an SDF-1 inhibitor, were undertaken, respectively, to investigate their effects on indirect revascularization. Two weeks later, the cortical microcirculation, neuronal damage, and functional outcome were evaluated according to the microvasculature density and partial pressure of brain tissue oxygen (PbtO2), regional blood flow, expression of phosphorylated Tau (pTau), TUNEL staining and the rotarod performance test, respectively.

Results

The cortical microcirculation, according to PbtO2 and regional blood flow, was impaired 3 weeks after BICAL. These impairments were improved by the EMS procedure. The regional blood flow was further increased by the addition of SDF-1 and decreased by the addition of AMD3100. Intramuscular injection of EPCs further increased the regional blood flow as compared with the EMS group. The rotarod test results showed that the functional outcome was best in the EMS combined with EPC injection group. Western blot analysis showed that the EMS combined with EPC treatment group had significantly decreased expressions of phosphorylated Tau and phosphorylated glycogen synthase kinase 3 beta (Y216 of GSK-3β). pTau and TUNEL-positive cells were markedly increased at 3 weeks after BICAL induction. Furthermore, the groups treated with EMS combined with SDF-1 or EPCs exhibited marked decreases in the pTau expression and TUNEL-positive cells, whereas AMD3100 treatment increased TUNEL-positive cells.

Conclusion

The results of this study suggested that indirect revascularization ameliorated the cerebral ischemic changes. EPCs played a key role in augmenting the effect of indirect revascularization in the treatment of chronic cerebral ischemia.

Neuroprotective Effects of an Edible Pigment Brilliant Blue FCF against Behavioral Abnormity in MCAO Rats

Ischemic stroke leads to hypoxia-induced neuronal death and behavioral abnormity, and is a major cause of death in the modern society. However, the treatments of this disease are limited. Brilliant Blue FCF (BBF) is an edible pigment used in the food industry that with multiple aromatic rings and sulfonic acid groups in its structure. BBF and its derivatives were proved to cross the blood-brain barrier and have advantages on the therapy of neuropsychiatric diseases. In this study, BBF, but not its derivatives, significantly ameliorated chemical hypoxia-induced cell death in HT22 hippocampal neuronal cell line. Moreover, protective effects of BBF were attributed to the inhibition of the extracellular regulated protein kinase (ERK) and glycogen synthase kinase-3β (GSK3β) pathways as evidenced by Western blotting analysis and specific inhibitors. Furthermore, BBF significantly reduced neurological and behavioral abnormity, and decreased brain infarct volume and cerebral edema induced by middle cerebral artery occlusion/reperfusion (MCAO) in rats. MCAO-induced increase of p-ERK in ischemic penumbra was reduced by BBF in rats. These results suggested that BBF prevented chemical hypoxia-induced otoxicity and MCAO-induced behavioral abnormity via the inhibition of the ERK and GSK3β pathways, indicating the potential use of BBF for treating ischemic stroke

Tanshinone IIA increased amniotic fluid volume through down-regulating placental AQPs expression via inhibiting the activity of GSK-3β

The mechanism of idiopathic oligohydramnios is still uncertain, and there is no effective and targeted treatment for it. Placental aquaporins (AQPs) were associated with idiopathic oligohydramnios. This study aimed to investigate the effect of tanshinone IIA on amniotic fluid volume (AFV) and its underlying molecular mechanisms related to placental AQPs (AQP1, AQP3, AQP8, AQP9). Results showed that compared with the women with normal AFV, placental AQP1, AQP3, AQP8, and AQP9 protein expressions were decreased in women with idiopathic oligohydramnios. Immunohistochemistry revealed localization of AQP1, AQP3, AQP8, and AQP9 mainly in trophoblast cells within labyrinth zone of mouse placenta. Also, AQP1 was located in fetal vascular endothelial cells. Pregnant mice were administered with tanshinone IIA (10 mg/kg or 50 mg/kg, n = 8, respectively) or vehicle (n = 8) from 9.5 to 18.5 gestational day (GD). Tanshinone IIA markedly increased the AFV in pregnant mice, without the effects on embryo numbers per litter, atrophic embryo rate, fetal weight, and placental weight, as well as increased the expressions of AQPs and inhibited the activity of GSK-3β in mice placenta. In JEG-3 cells, tanshinone IIA downregulated AQP1, AQP3, AQP8, AQP9 expressions and inhibited the activity of GSK-3β. Activating GSK-3β with MK-2206 eliminated these alterations. Thus, tanshinone IIA could increase AFV in pregnant mice, possibly through downregulating placental AQP1, AQP3, AQP8, and AQP9 expression via inhibiting the activity of GSK-3β. Tanshinone IIA may be optional for the treatment of idiopathic oligohydramnios.

Recent Research Progress (2015-2021) and Perspectives on the Pharmacological Effects and Mechanisms of Tanshinone IIA

Tanshinone IIA (Tan IIA) is an important characteristic component and active ingredient in Salvia miltiorrhiza, and its various aspects of research are constantly being updated to explore its potential application. In this paper, we review the recent progress on pharmacological activities and the therapeutic mechanisms of Tan IIA according to literature during the years 2015-2021. Tan IIA shows multiple pharmacological effects, including anticarcinogenic, cardiovascular, nervous, respiratory, urinary, digestive, and motor systems activities. Tan IIA modulates multi-targets referring to Nrf2, AMPK, GSK-3β, EGFR, CD36, HO-1, NOX4, Beclin-1, TLR4, TNF-α, STAT3, Caspase-3, and bcl-2 proteins and multi-pathways including NF-κB, SIRT1/PGC1α, MAPK, SREBP-2/Pcsk9, Wnt, PI3K/Akt/mTOR pathways, TGF-β/Smad and Hippo/YAP pathways, etc., which directly or indirectly influence disease course. Further, with the reported targets, the potential effects and possible mechanisms of Tan IIA against diseases were predicted by bioinformatic analysis. This paper provides new insights into the therapeutic effects and mechanisms of Tan IIA against diseases.

Bushen-Huatan-Yizhi formula reduces spatial learning and memory challenges through inhibition of the GSK-3β/CREB pathway in AD-like model rats

BACKGROUND

There is an increase in cases of Alzheimer's disease (AD) stemming from a globally ageing population demographic. Although substantial research efforts were performed for the scope of prophylaxis and therapeutic measure development against AD, based on its pathogenesis, most were unsuccessful. Bushen-Huatan-Yizhi formula (BSHTYZ) is extensively implemented to manage dementia. However, few studies have been carried out to understand how BSHTYZ enhances recovery of spatial learning and memory and how it modulates relevant molecular interplays in order to achieve this.

PURPOSE

To investigate neuroprotective function, ameliorating learning/memory capacity of BSHTYZ via GSK-3β / CREB signaling pathway in rat AD models influenced through Aβ1-42.

METHODS

A total of 60 male SD rats (3 months old) were randomized into six groups and treated with 2.6 μg/μl Aβ1-42 (5 μl) into the lateral ventricle, though the control group (Con) was administered an equivalent volume of vehicle. Consequently, the rat cohorts were administered either BSHTYZ or donepezil hydrochloride or normal saline, by intragastric administration, for four weeks. Spatial learning / memory were detected through the Morris water maze, and possible mechanisms detected by histomorphological examination and Western blot in the rat AD models induced by Aβ1-42.

RESULTS

Spatial learning/memory issues were monitored after Aβ1-42 infusion in rats. Simultaneously, neuron loss in cornuammonis1 (CA1) / dentate gyrus (DG) within hippocampus region were identified, together with enhanced black granule staining within the hippocampus and hyperphosphorylated tau within Ser202 and Ser396 sites. It was also elucidated that Aβ1-42 had the capacity to up-regulate glycogen synthase kinase-3β (GSK-3β) and down-regulate cAMP response element binding protein (CREB). BSHTYZ was found to reverse such molecular interplays.

CONCLUSION

The study suggested BSHTYZ could possibly provide neuroprotective role against learning / memory impairment, which provided a potential therapeutic tool delaying the progression of AD molecular interplays that includes the GSK-3β / CREB signaling pathway.

Natural Compounds as Medical Strategies in the Prevention and Treatment of Psychiatric Disorders Seen in Neurological Diseases

Psychiatric disorders are frequently encountered in many neurological disorders, such as Alzheimer’s and Parkinson diseases along with epilepsy, migraine, essential tremors, and stroke. The most common comorbid diagnoses in neurological diseases are depression and anxiety disorders along with cognitive impairment. Whether the underlying reason is due to common neurochemical mechanisms or loss of previous functioning level, comorbidities are often overlooked. Various treatment options are available, such as pharmacological treatments, cognitive-behavioral therapy, somatic interventions, or electroconvulsive therapy. However oral antidepressant therapy may have some disadvantages, such as interaction with other medications, low tolerability due to side effects, and low efficiency. Natural compounds of plant origin are extensively researched to find a better and safer alternative treatment. Experimental studies have shown that phytochemicals such as alkaloids, terpenes, flavonoids, phenolic acids as well as lipids have significant potential in in vitro and in vivo models of psychiatric disorders. In this review, various efficacy of natural products in in vitro and in vivo studies on neuroprotective and their roles in psychiatric disorders are examined and their neuro-therapeutic potentials are shed light.

Tanshinone IIA: A phytochemical as a promising drug candidate for neurodegenerative diseases

Tanshinones, lipophilic diterpenes isolated from the rhizome of Salvia miltiorrhiza, have diverse pharmacological activities against human ailments including neurological diseases. In fact, tanshinones have been used to treat heart diseases, stroke, and vascular diseases in traditional Chinese medicine. During the last decade, tanshinones have been the most widely studied phytochemicals for their neuroprotective effects against experimental models of cerebral ischemia and Alzheimer's diseases. Importantly, tanshinone IIA, mostly studied tanshinone for biological activities, is recently reported to attenuate blood-brain barrier permeability among stroke patients, suggesting tanshinone IIA as an appealing therapeutic candidate for neurological diseases. Tanshinone I and IIA are also effective in experimental models of Parkinson's disease, Multiple sclerosis, and other neuroinflammatory diseases. In addition, several experimental studies suggested the pleiotropic neuroprotective effects of tanshinones such as anti-inflammatory, antioxidant, anti-apoptotic, and BBB protectant further value aiding to tanshinone as an appealing therapeutic strategy in neurological diseases. Therefore, in this review, we aimed to compile the recent updates and cellular and molecular mechanisms of neuroprotection of tanshinone IIA in diverse neurological diseases.

Suan-Zao-Ren Decoction ameliorates synaptic plasticity through inhibition of the Aβ deposition and JAK2/STAT3 signaling pathway in AD model of APP/PS1 transgenic mice

Background

Suan-Zao-Ren Decoction (SZRD) has been widely used to treat neurological illnesses, including dementia, insomnia and depression. However, the mechanisms underlying SZRD’s improvement in cognitive function remain unclear. In this study, we examined SZRD’s effect on APP/PS1 transgenic mice and mechanisms associated with SZRD’s action in alleviating neuroinflammation and improving synaptic plasticity.

Methods

The APP/PS1 mice were treated with different dosages of SZRD (12.96 and 25.92 g/kg/day, in L-SZRD and H-SZRD groups, respectively) for 4 weeks. Morris water maze was conducted to determine changes in behaviors of the mice after the treatment. Meanwhile, in the samples of the hippocampus, Nissl staining and Golgi-Cox staining were used to detect synaptic plasticity. ELISA was applied to assess the expression levels of Aβ₁₋₄₀ and Aβ₁₋₄₂ in the hippocampus of mice. Western blot (WB) was employed to test the protein expression level of Aβ₁₋₄₂, APP, ADAM10, BACE1, PS1, IDE, IBA1, GFAP, PSD95 and SYN, as well as the expressions of JAK2, STAT3 and their phosphorylation patterns to detect the involvement of JAK2/STAT3 pathway. Besides, we examined the serum and hippocampal contents of IL-1β, IL-6 and TNF-α through ELISA.

Results

Compared to the APP/PS1 mice without any treatment, SZRD, especially the L-SZRD, significantly ameliorated cognitive impairment of the APP/PS1 mice with decreases in the loss of neurons and Aβ plaque deposition as well as improvement of synaptic plasticity in the hippocampus (P < 0.05 or 0.01). Also, SZRD, in particular, the L-SZRD markedly inhibited the serum and hippocampal concentrations of IL-6, IL-1β and TNF-α, while reducing the expression of p-JAK2-Tyr1007 and p-STAT3-Tyr705 in the hippocampus of the APP/PS1 mice (P < 0.05 or 0.01).

Conclusions

The SZRD, especially the L-SZRD, may improve the cognitive impairment and ameliorate the neural degeneration in APP/PS1 transgenic mice through inhibiting Aβ accumulation and neuroinflammation via the JAK2/STAT3 pathway.

Tanshinone IIA: A Review of its Anticancer Effects

Tanshinone IIA (Tan IIA) is a pharmacologically lipophilic active constituent isolated from the roots and rhizomes of the Chinese medicinal herb Salvia miltiorrhiza Bunge (Danshen). Tan IIA is currently used in China and other neighboring countries to treat patients with cardiovascular system, diabetes, apoplexy, arthritis, sepsis, and other diseases. Recently, it was reported that tan IIA could have a wide range of antitumor effects on several human tumor cell lines, but the research of the mechanism of tan IIA is relatively scattered in cancer. This review aimed to summarize the recent advances in the anticancer effects of tan IIA and to provide a novel perspective on clinical use of tan IIA.

Apolipoprotein J in Alzheimer's Disease: Shedding Light on Its Role with Cell Signaling Pathway Perspective and Possible Therapeutic Approaches

Apolipoprotein J (ApoJ), or clusterin, is one of the main apolipoproteins in the brain. It is synthesized and released from astrocytes in a healthy brain, and its expression increases in neurodegenerative disorders. Genetic evidence has suggested an association between ApoJ polymorphism and the risk of Alzheimer's disease (AD)-it is now considered the third main genetic risk factor for late-onset AD. However, the role of ApoJ overexpression in the state of disorder, toxicity, or protection is not yet clear. Since ApoJ plays different roles in AD, we review the function of ApoJ using different cell signaling pathways in AD and outline its paradoxical roles in AD. ApoJ helps in amyloid-beta (Aβ) clearance. Vice versa, ApoJ gene knock-out causes fibrillary Aβ reduction and prevents Aβ-induced neuron cell death. Understanding ApoJ, through various cellular signaling pathways, creates a new perspective on AD's cellular principles. The overall message is that ApoJ can be a valuable tool in controlling AD.

Prospective therapeutic potential of Tanshinone IIA: An updated overview

In the past decades, the branch of complementary and alternative medicine based therapeutics has gained considerable attention worldwide. Pharmacological efficacy of various traditional medicinal plants, their products and/or product derivatives have been explored on an increasing scale. Tanshinone IIA (Tan IIA) is a pharmacologically active lipophilic component of Salvia miltiorrhiza extract. Tan IIA shares a history of high repute in Traditional Chinese Medicine. Reckoning with these, the present review collates the pharmacological properties of Tan IIA with a special emphasis on its therapeutic potential against diverse diseases including cardiovascular diseases, cerebrovascular diseases, cancer, diabetes, obesity and neurogenerative diseases. Further, possible applications of various therapeutic preparations of Tan IIA were discussed with special emphasis on nano-based drug delivery formulations. Considering the tremendous advancement in the field of nanomedicine and the therapeutic potential of Tan IIA, the convergence of these two aspects can be foreseen with great promise in clinical application.

Pharmacological Activity and Mechanism of Tanshinone IIA in Related Diseases

Salvia miltiorrhiza: (Danshen) is a significant (traditional Chinese medication) natural remedy, enhancing blood circulation and clear blood stasis. In this view, it is widely used against several heart diseases, eg, cardiomyopathy, arrhythmia, and congenital heart defects. Tanshinone IIA (tan-IIA) is the main fat-soluble component of Salvia miltiorrhiza. Modern pharmacological study shows that tan-IIA has anti-inflammatory and anti-oxidant activities. Tan-IIA induces remarkable cardioprotective effects via enhancing angiogenesis which may serve as an effective treatment against cardiovascular diseases (CVD). There is also evidence that tan-IIA has extensive immunomodulatory effects and plays a significant role in the development and function of immune cells. Tan-IIA reduces the production of inflammatory mediators and restores abnormal signaling pathways via regulating the function and activation of immune cells. It can also regulate signal transduction pathways, ie, TLR/NF-κB pathway and MAPKs/NF-κB pathway, thereby tan-IIA has an anti-inflammatory, anticoagulant, antithrombotic and neuroprotective role. It plays a protective role in the pathogenesis of cardiovascular disorders (ie, atherosclerosis, hypertension) and Alzheimer’s disease. It has also been revealed that tan-IIA has an anti-tumor role by killing various tumor cells, inducing differentiation and apoptosis, and has potential activity against carcinoma progression. In the review of this fact, the tan-IIA role in different diseases and its mechanism have been summarized while its clinical applications are also explored to provide a new perspective of Salvia miltiorrhiza. An extensive study on the mechanism of action of tan-IIA is of great significance for the effective use of Chinese herbal medicine and the promotion of its status and influence on the world.

Specific Degradation of Endogenous Tau Protein and Inhibition of Tau Fibrillation by Tanshinone IIA through the Ubiquitin-Proteasome Pathway

Alzheimer's disease (AD) is a common neurodegenerative disease which is partly characterized by the aggregation of hyperphosphorylated Tau proteins forming neurofibrillary tangles that promote AD pathogenesis. In this study, we investigated the effects of tanshinone IIA (Tan IIA) isolated from Salvia miltiorrhiza on Tau degradation in the treatment of AD. The results showed that Tan IIA reduced the Tau expression and attenuated Tau phosphorylation in N2a cells, Tau-overexpressing cells, and 3×Tg-AD mouse primary neuron cells. Moreover, Tan IIA increased polyubiquitinated Tau accumulation and induced proteasomal degradation of the Tau protein. Additionally, Tan IIA became bound to the Tau protein and inhibited the formation of heparin-induced Tau fibrils. In summary, Tan IIA can increase polyubiquitinated Tau accumulation and induce the proteasomal degradation of the Tau protein and the binding of Tan IIA to the Tau protein, inhibiting the formation of Tau fibrils. Tan IIA may be further explored as a potential candidate for AD treatment.

Rapid Identification of Tanshinone IIA Metabolites in an Amyloid-β1-42 Induced Alzherimer's Disease Rat Model using UHPLC-Q-Exactive Qrbitrap Mass Spectrometry

Alzheimer’s disease (AD) is a neurodegenerative disorder that damages health and welfare of the elderly, and there has been no effective therapy for AD until now. It has been proved that tanshinone IIA (tan IIA) could alleviate pathological symptoms of AD via improving non-amyloidogenic cleavage of amyloid precursor protein, decreasing the accumulations of p-tau and amyloid-β_1–42 (Aβ_1–42), and so forth. However, the further biochemical mechanisms of tan IIA are not clear. The experiment was undertaken to explore metabolites of tan IIA in AD rats induced by microinjecting Aβ_1-42 in the CA1 region of hippocampus. AD rats were orally administrated with tan IIA at 100 mg/kg weight, and plasma, urine, faeces, kidney, liver and brain were then collected for metabolites analysis by UHPLC-Q-Exactive Qrbitrap mass spectrometry. Consequently, a total of 37 metabolites were positively or putatively identified on the basis of mass fragmentation behavior, accurate mass measurements and retention times. As a result, methylation, hydroxylation, dehydration, decarbonylation, reduction reaction, glucuronidation, glycine linking and their composite reactions were characterized to illuminate metabolic pathways of tan IIA in vivo. Several metabolites presented differences in the distribution of tan IIA between the sham control and the AD model group. Overall, these results provided valuable references for research on metabolites of tan IIA in vivo and its probable active structure for exerting neuroprotection.