Astragaloside IV suppresses post-ischemic natural killer cell infiltration and activation in the brain: involvement of histone deacetylase inhibition

Electroacupuncture suppresses NK cell infiltration and activation in the ischemic mouse brain through STAT3 inhibition

AIMS

Electroacupuncture (EA) at Shuigou (GV26) and Baihui (GV20) has shown therapeutic benefits for stroke patients. Given that natural killer (NK) cell infiltration into the brain significantly contributes to the exacerbation of cerebral ischemic injury, this study investigated the impact of EA at Shuigou (GV26) and Baihui (GV20) on post-ischemic brain infiltration and activation of NK cells.

METHODS

Neurological deficit score, rotarod test, adhesive removal test, and TTC staining were used to evaluate the beneficial effects of EA in middle cerebral artery occlusion (MCAO) mice. The inhibitory effect of EA on STAT3 activation was assessed using Western blot. Flow cytometry was used to explore the impact of EA on post-ischemic brain infiltration of NK cells, as well as the activating receptor NKG2D expression and interferon-γ (IFN-γ) production by these infiltrated NK cells.

RESULTS

EA significantly alleviated neurological functional deficits and reduced brain infarction in MCAO mice. Abundant NK cells infiltrated into the ischemic hemisphere, but this infiltration was significantly suppressed by EA. Furthermore, EA attenuated NKG2D levels and reduced production of IFN-γ by NK cells in the ischemic brain. Notably, EA's inhibitory effect on post-ischemic NK cell brain infiltration and activation was comparable to that of STAT3 inhibition. The combination of EA and STAT3 inhibition did not result in further enhancement of the inhibitory effect. Moreover, the protective effects of EA against MCAO injury were abolished when STAT3 was activated.

CONCLUSION

Our findings suggest that EA at Shuigou (GV26) and Baihui (GV20) inhibits the post-ischemic brain infiltration and activation of NK cells through STAT3 inhibition, significantly contributing to its therapeutic effects against brain ischemia.

Chemical Composition and Therapeutic Effects of Several Astragalus Species (Fabaceae)

The review integrates information on the component composition and biological activity of some Astragalus L. (Fabaceae) species from studies reported over the past 5-7 years. The aerial and underground parts of 34 Astragalus species contain triterpene saponins, flavonoids, polysacharides, tannins, free organic acids, higher fatty acids, vitamins, trace elements, and other constituents. Among the Astragalus species, A. membranaceus (Fisch.) Bunge is the best studied in terms of component composition and biological activity. Anti-inflammatory, immunomodulatory, antioxidant, anticancer, cardioprotective, and hepathoprotective activities have been experimentally detected in total bioactive substances, fractions, and individual compounds extracted from various parts of A. membranaceus and A. membranaceus var. mongholicus in vitro and in vivo. The composition and biological effects of other Astragalus species are still poorly understood. The review summarizes the recent advances in studying new compounds extracted from Astragalus species and their biological activities.

Phytogenic feed additives as natural antibiotic alternatives in animal health and production: A review of the literature of the last decade

The use of antibiotics in animal production raises great public safety concerns; therefore, there is an urgent need for the development of substitutes for antibiotics. In recent decades, plant-derived feed additives have been widely investigated as antibiotic alternatives for use in animal health and production because they exert multiple biological functions and are less likely to induce resistance development. This review summarizes the research history and classification of phytogenic feed additives and their main functions, potential modes of action, influencing factors, and potential negative effects. Further, we highlight the challenges in developing sustainable, safe, and affordable plant-derived antibiotic alternatives for use in livestock production.

Astragaloside IV: A promising natural neuroprotective agent for neurological disorders

Neurological disorders are characterized by high morbidity, disability, and mortality rates, which seriously threaten human health. However, clinically satisfactory agents for treatment are still currently lacking. Therefore, finding neuroprotective agents with minimum side effects and better efficacy is a challenge. Chinese herbal medicine, particularly natural preparations extracted from herbs or plants, has become an unparalleled resource for discovering new agent candidates. Astragali Radix is an important Qi tonic drug in traditional Chinese medicine and has a long medicinal history. As a natural medicine, it has a good prevention and treatment effect on neurological disorders. Here, the role and mechanism of astragaloside IV in the treatment of neurological disorders were evaluated and discussed through previous research results. Related information from major scientific databases, such as PubMed, MEDLINE, Web of Science, ScienceDirect, Embase, BIOSIS Previews, and the Cochrane Central Register of Controlled Trials and Cochrane Library, covering between 2001 and 2021 was compiled, using "Astragaloside IV" and "Neurological disorders," "Astragaloside IV," and "Neurodegenerative diseases" as reference terms. By summarizing previous research results, we found that astragaloside IV may play a neuroprotective role through various mechanisms: anti-inflammatory, anti-oxidative, anti-apoptotic protection of nerve cells and regulation of nerve growth factor, as well as by inhibiting neurodegeneration and promoting nerve regeneration. Astragaloside IV is a promising natural neuroprotective agent. By determining its pharmacological mechanism, astragaloside IV may be a new candidate drug for the treatment of neurological disorders.

The protective effect of Buzhong Yiqi decoction on ischemic stroke mice and the mechanism of gut microbiota

Buzhong Yiqi decoction (BZYQD) has been developed for preventing or reducing the recurrence of ischemic stroke for a long time in China. However, the mechanism of action of the BZYQD is not completely understood. Our research aims to determine whether the mechanism of action of BZYQD is by regulating gut microbiota using 16SR RNA and fecal microbiota transplantation. In a cerebral ischemia mouse model, the results showed that prophylactic administration of BZYQD could reduce brain infarct volume and improve neurological function and behavior. The prophylactic administration of BZYQD could regulate intestinal microbiota and increase the abundance of butyrate-producing Prevotellaceae_NK3B31_group and probiotic Akkermansia in mice 72 h after surgery. Transplanting BZYQD-administered bacterial flora into antibiotic-depleted mice could reproduce the therapeutic effects of BZYQD. Overall, our study provided molecular insights into the mechanism and impact of BZYQD in the prevention of cerebral ischemic damage and highlighted the potential of regulation of intestinal microbiota as a therapeutic approach for ischemic stroke.

A Review of Traditional Chinese Medicine, Buyang Huanwu Decoction for the Treatment of Cerebral Small Vessel Disease

Cerebral small vessel disease (CSVD) is often referred to as “collaterals disease” in traditional Chinese medicine (TCM), and commonly includes ischemic and hemorrhagic CSVD. TCM has a long history of treating CSVD and has demonstrated unique efficacy. Buyang Huanwu Decoction (BHD) is a classical TCM formula that has been used for the prevention and treatment of stroke for hundreds of years. BHD exerts its therapeutic effects on CSVD through a variety of mechanisms. In this review, the clinical and animal studies on BHD and CSVD were systematically introduced. In addition, the pharmacological mechanisms, active components, and clinical applications of BHD in the treatment of CSVD were reviewed. We believe that an in-depth understanding of BHD, its pharmacological mechanism, disease-drug interaction, and other aspects will help in laying the foundation for its development as a new therapeutic strategy for the treatment of CSVD.

A randomized controlled clinical trial of the effects of range of motion exercises and massage on muscle strength in critically ill patients

BACKGROUND

Atrophy and muscle weakness is a common problem in critically ill patients admitted to the intensive care unit (ICU). Muscle weakness in severe cases can lead to tetraplegia, reduced or lost tendon reflexes, delayed weaning from mechanical ventilation, physical disability, and increased mortality. The aim of this study was to compare the effects of range of motion exercises (ROM) and massage on muscle strength of the patients admitted to ICUs.

METHODS

This study was a single-blinded randomized controlled trial conducted in ICUs of Afzalipour hospital in Kerman, southeastern Iran. Ninety conscious ICU patients were randomly divided into three groups (massage, ROM exercises and control). The researcher/co-researcher massaged or did ROM exercises on the patients' extremities once a day for seven consecutive days. Using a hand-held dynamometer, the co-researcher, rated the muscle strength before, on the fourth and seventh days of intervention at 8 p.m.

RESULTS

The mean muscles strength of the right arm in the ROM exercise and massage groups increased by 0.63 kg, and 0.29 kg, respectively after the intervention compared with before the intervention. The muscle strength of the right arm in the control group reduced by 0.55 kg. The mean muscles strength of the left arm in the ROM exercise and massage groups increased by 0.61 kg and 0.28 kg after the intervention, respectively while it reduced by 0.56 kg in the control group. The mean muscles strength of the right leg in the ROM exercise and massage groups increased by 0.53 kg and 0.27 kg after the intervention compared with before the intervention while it reduced by 0.70 kg in the control group. The mean muscles strength of the left leg in the ROM exercise and massage groups increased by 0.54 kg and 0.26 kg after the intervention compared with before the intervention while it reduced by 0.71 kg in the control group.

CONCLUSION

The results of the present study showed that ROM exercises and massage were effective interventions in increasing muscle strength of the critically ill patients admitted to intensive care units.

Peri-ampullary diverticulum was associated with a higher rate of acute cholangitis among patients with choledocholithiasis

BACKGROUND

Choledocholithiasis is a commonly encountered disease that is associated with various clinical presentations ranging from mild form of biliary colic to severe life-threatening acute cholangitis. Recently, peri-ampullary diverticulum (PAD) has been linked to the development of biliary diseases; however, data regarding its association with the development of acute cholangitis in the setting of choledocholithiasis are scarce.

AIMS

We aimed to identify predictors, specifically PAD, for the development of acute cholangitis in patients with choledocholithiasis.

METHODS

We performed a retrospective cross-sectional study of all patients admitted to Galilee Medical Center from 1 January 2010 to 31 December 2019 with different clinical presentations of documented choledocholithiasis including cholangitis, biliary pancreatitis, and biliary colic with abnormal liver enzymes.

RESULTS

Overall, 651 patients were included in the final analysis. Among them, 88 patients (13.5%) had choledocholithiasis associated with acute cholangitis (group A), as compared to 563 patients (86.5%) without acute cholangitis (group B). The average ages in groups A and B were 77.8 ± 13.6 and 62.4 ± 20.4 years, respectively (P < 0.0001). The rate of PAD was significantly higher in group A as compared to group B (35.2% vs. 19%, P = 0.0002). However, the rate of smoking, chronic liver diseases, hemolytic anemia, and post-cholecystectomy status were not different between the groups (P = 0.3, P = 0.3, P = 0.2, and P = 0.3), respectively. On univariate analysis, age (OR 1.05, P < 0.0001) and PAD (OR 2.32, P = 0.0006) were significantly associated with acute cholangitis. On multivariate logistic regression analysis, the effects of age and PAD were preserved (OR 1.05, 95% CI 1.03-1.07, P < 0.0001 and OR 1.64, 95% CI 1.02-2.72, P = 0.049), respectively.

CONCLUSION

PAD showed a significant association with the development of acute cholangitis among patients with choledocholithiasis. Identification of gallbladder and biliary stones in patients with PAD is of paramount importance since early diagnosis and treatment might prevent further life-threatening complications.

Biological active ingredients of Astragali Radix and its mechanisms in treating cardiovascular and cerebrovascular diseases

BACKGROUND

With the rising age of the global population, the incidence rate of cardiovascular and cerebrovascular diseases (CCVDs) is increasing, which causes serious public health burden. The efforts for new therapeutic approaches are still being sought since the treatment effects of existing therapies are not quite satisfactory. Chinese traditional medicine proved to be very efficient in the treatment of CCVDs. Well described and established in Chinese medicine, Astragali Radix, has been commonly administered in the prophylaxis and cure of CCVDs for thousands of years.

PURPOSE

This review summarized the action mode and mechanisms of Astragali Radix phytochemicals on CCVDs, hoping to provide valuable information for the future application, development and improvement of Astragali Radix as well as CCVDs treatment.

METHODS

A plenty of literature on biological active ingredients of Astragali Radix used for CCVDs treatment were retrieved from online electronic PubMed and Web of Science databases.

RESULTS

This review highlighted the effects of five main active components in Astragali Radix including astragaloside Ⅳ, cycloastragenol, astragalus polysaccharide, calycosin-7-O-β-d-glucoside, and calycosin on CCVDs. The mechanisms mainly involved anti-oxidative damage, anti-inflammatory, and antiapoptotic through signaling pathways such as PI3K/Akt, Nrf2/HO-1, and TLR4/NF-κB pathway. In addition, the majority active constituents in AR have no obvious toxic side effects.

CONCLUSION

The main active components of Astragali Radix, especially AS-IV, have been extensively summarized. It has been proved that Astragali Radix has obvious therapeutic effects on various CCVDs, including myocardial and cerebral ischemia, hypertension, atherosclerosis, cardiac hypertrophy, chronic heart failure. CAG possesses anti-ischemia activity without toxicity, indicating a worthy of further development. However, high-quality clinical and pharmacokinetic studies are required to validate the current studies.

The Role of CCL2/CCR2 Axis in Cerebral Ischemia-Reperfusion Injury and Treatment: From Animal Experiments to Clinical Trials

C-C motif chemokine ligand 2 (CCL2) is a member of the monocyte chemokine protein family, which binds to its receptor CCR2 to induce monocyte infiltration and mediate inflammation. The CCL2/CCR2 signaling pathway participates in the transduction of neuroinflammatory information between all types of cells in the central nervous system. Animal studies and clinical trials have shown that CCL2/CCR2 mediate the pathological process of ischemic stroke, and a higher CCL2 level in serum is associated with a higher risk of any form of stroke. In the acute phase of cerebral ischemia-reperfusion, the expression of CCL2/CCR2 is increased in the ischemic penumbra, which promotes neuroinflammation and enhances brain injury. In the later phase, it participates in the migration of neuroblasts to the ischemic area and promotes the recovery of neurological function. CCL2/CCR2 gene knockout or activity inhibition can reduce the nerve inflammation and brain injury induced by cerebral ischemia-reperfusion, suggesting that the development of drugs regulating the activity of the CCL2/CCR2 signaling pathway could be used to prevent and treat the cell injury in the acute phase and promote the recovery of neurological function in the chronic phase in ischemic stroke patients.

Suppressing NK Cells by Astragaloside IV Protects Against Acute Ischemic Stroke in Mice Via Inhibiting STAT3

Natural killer (NK) cells, a key member of innate lymphocytes, are a promising immunotherapeutic target for ischemic stroke. Astragaloside IV (ASIV) is isolated from Astragalus mongholicus Bunge (Fabaceae), a herbal medicine possessing immunomodulatory ability. This study investigated the effect of ASIV on NK cells during the acute stage of brain ischemic injury in a mouse model of middle cerebral artery occlusion (MCAO). MCAO mice treated with ASIV had better functional outcomes, smaller brain infarction and less NK cell brain infiltration. NK cell depletion echoed the protective effect of ASIV. Notably, ASIV did not enhance the protective effect of NK cell depletion against brain ischemic injury. ASIV inhibited glial cell-derived CCL2-mediated chemotaxis to prevent post-ischemic NK cell brain recruitment. Meanwhile, ASIV also abrogated NK cell-mediated cytolytic killing of neurons subjected to oxygen-glucose deprivation and suppressed NK cell-derived IFN-γ and NKG2D expression in the ischemic brain. The inhibitory effect of ASIV on NK cell brain infiltration and activation was mimicked by cryptotanshinone, a STAT3 inhibitor. There was no additive effect when ASIV and cryptotanshinone were used together. In conclusion, ASIV inhibits post-ischemic brain infiltration and activation of NK cells through STAT3 suppression, and this inhibitory effect of ASIV on NK cells plays a key role in its protection against acute ischemic brain injury. Our findings suggest that ASIV is a promising therapeutic candidate in NK cell-based immunotherapy for the treatment of acute ischemic stroke and pave the way for potential clinical trials.

Construction of a ceRNA immunoregulatory network related to the development of vascular dementia through a weighted gene coexpression network analysis

Background

To date, vascular dementia (VaD) lacks effective treatment in clinical practice. There is also growing evidence that VaD may be closely related to the immune response. The development of high-throughput technology, and the recently discovered group of new mediators called competitive endogenous RNAs (ceRNA), provides a unique opportunity to study the immunomodulation of VaD.

Methods

In this study, we used gene expression profiles in the Gene Expression Omnibus (GEO) database to obtain immune-related gene coexpression modules through a weighted gene coexpression network analysis (WGCNA) and gene enrichment analysis. We extracted and merged long non-coding RNA (lncRNA) and microRNA (miRNA) expressions from the GEO database and mapped them with related databases. Subsequently, we used Cytoscape to construct a lncRNA-miRNA-mRNA network, and then we performed an enrichment analysis on the mRNAs in the network to determine their regulatory function. Subsequently, we used an ImmuCellAI immune infiltration analysis and constructed a ceRNA sub-network of related immune cells. Finally, we conducted a gene set enrichment analysis (GSEA) to determine the potential regulatory pathways of the key factors.

Results

As a result, we identified the blue module as the key module of immunity and constructed the related CeRNA network. Immune infiltration analysis showed that natural killer T (NKT) cells may be the key immune cells of VaD. Using a Pearson correlation analysis, we identified that B4GALT1, PPP1R3B, MICB, HHAT, DSC2, DNA2, SCARA3, and lncRNA NEAT1 may be the key factors of VaD. Our subsequent GSEA analysis showed that lncRNA NEAT1 may be regulated by NK cells and toll-like receptors.

Conclusions

Our research provides new therapeutic targets for vascular dementia from the immunological perspective for the first time, including B4GALT1, PPP1R3B, MICB, HHAT, DSC2, DNA2, SCARA3, and lncRNA NEAT1, and our research hopes to provide new treatment options for VaD.