Sinomenine in Cardio-Cerebrovascular Diseases: Potential Therapeutic Effects and Pharmacological Evidences

Antioxidant Activity and the Therapeutic Effect of Sinomenine Hydrochloride-Loaded Liposomes-in-Hydrogel on Atopic Dermatitis

Sinomenine hydrochloride is an excellent drug with anti-inflammatory, antioxidant, immune-regulatory, and other functions. Atopic dermatitis is an inherited allergic inflammation that causes itchiness, redness, and swelling in the affected area, which can have a significant impact on the life of the patient. There are many therapeutic methods for atopic dermatitis, and sinomenine with immunomodulatory activity might be effective in the treatment of atopic dermatitis. In this study, the atopic dermatitis model was established in experimental mice, and physical experiments were carried out on the mice. In the experiment, sinomenine hydrochloride liposomes-in-hydrogel as a new preparation was selected for delivery. In this case, liposomes were dispersed in the colloidal hydrogel on a mesoscopic scale and could provide specific transfer properties. The results showed that the sinomenine hydrochloride-loaded liposomes-in-hydrogel system could effectively inhibit atopic dermatitis.

Investigating the therapeutic potential of sinomenine in rheumatoid arthritis: anti-inflammatory, antioxidant, and immunomodulatory mechanisms

An autoimmune disease, rheumatoid arthritis (RA) is characterized by the onset of inflammation and subsequent damage to the joints. Although several therapies are available for RA, none are effective, and many have undesirable side effects. The roots of Sinomenium acutum produce an alkaloid called Sinomenine (SIN), which has been used for centuries in Chinese medicine to treat arthritis due to its anti-inflammatory properties. This study aimed to explore the potential therapeutic benefits of SIN through oral administration following RA induction using Freund's complete adjuvant (FCA) injections. The study monitored changes in the arthritic index, hind paw volume, inflammation and oxidative stress markers. Results demonstrated that SIN effectively inhibited the activity of NF-κB and IKKβ in knee joint tissues, which led to a decrease in tissue levels of TNF-α, IL-6, IL-1β, and iNOS in RA-induced rats. The production of anti-inflammatory cytokines such as IL-10, Arg-1, and Fizz1 also increased. In rat knee joints, SIN elevated the expression of TIMP-1 and TIMP-3 and decreased the expression of MMP-2 and MMP-9. Additionally, SIN modulated the RANK/RANKL/OPG pathway in RA-induced rat knee joint tissues, reducing RANKL expression and increasing OPG. SIN also effectively decreased MDA, NO, and elevated antioxidant enzymes (SOD, CAT, GPx, and GSH) in RA-induced rats via Nrf2/Keap 1 signaling pathway activation. In conclusion, this study suggests that SIN possesses potential therapeutic benefits for treating RA by modulating the RANK/RANKL/OPG pathway, which may impact osteoclast activity, oxidative stress, and inflammation in knee joint tissues.

Natural L-type calcium channels antagonists from Chinese medicine

L-type calcium channels (LTCCs), the largest subfamily of voltage-gated calcium channels (VGCCs), are the main channels for Ca2+ influx during extracellular excitation. LTCCs are widely present in excitable cells, especially cardiac and cardiovascular smooth muscle cells, and participate in various Ca2+-dependent processes. LTCCs have been considered as worthy drug target for cardiovascular, neurological and psychological diseases for decades. Natural products from Traditional Chinese medicine (TCM) have shown the potential as new drugs for the treatment of LTCCs related diseases. In this review, the basic structure, function of LTCCs, and the related human diseases caused by structural or functional abnormalities of LTCCs, and the natural LTCCs antagonist and their potential usages were summarized.

Sinomenine Hydrochloride Protects IgA Nephropathy Through Regulating Cell Growth and Apoptosis of T and B Lymphocytes

Purpose

Sinomenine hydrochloride (SH) is used to treat chronic inflammatory diseases such as rheumatoid arthritis and may also be efficacious against Immunoglobulin A nephropathy (IgAN). However, no trial has investigated the molecular mechanism of SH on IgAN. Therefore, this study aims to investigate the effect and mechanism of SH on IgAN.

Methods

The pathological changes and IgA and C3 depositions in the kidney of an IgAN rat model were detected by periodic acid-Schiff (PAS) and direct immunofluorescence staining. After extracting T and B cells using immunomagnetic beads, we assessed their purity, cell cycle phase, and apoptosis stage through flow cytometry. Furthermore, we quantified cell cycle-related and apoptosis-associated proteins by Western blotting.

Results

SH reduced IgA and C3 depositions in stage 4 IgAN, thereby decreasing inflammatory cellular infiltration and mesangial injury in an IgAN model induced using heteroproteins. Furthermore, SH arrested the cell cycle of lymphocytes T and B from the spleen of IgAN rats. Regarding the mechanism, our results demonstrated that SH regulated the Cyclin D1 and Cyclin E1 protein levels for arresting the cell cycle and it also regulated Bax and Bcl-2 protein levels, thus increasing Cleaved caspase-3 protein levels in Jurkat T and Ramos B cells.

Conclusion

SH exerts a dual regulation on the cell cycle and apoptosis of T and B cells by controlling cell cycle-related and apoptosis-associated proteins; it also reduces inflammatory cellular infiltration and mesangial proliferation. These are the major mechanisms of SH in IgAN.

Sinomenine attenuates bleomycin-induced pulmonary fibrosis, inflammation, and oxidative stress by inhibiting TLR4/NLRP3/TGFβ signaling

OBJECTIVE

The present work concentrated on validating whether sinomenine alleviates bleomycin (BLM)-induced pulmonary fibrosis, inflammation, and oxidative stress.

METHODS

A rat model of pulmonary fibrosis was constructed through intratracheal injection with 5 mg/kg BLM, and the effects of 30 mg/kg sinomenine on pulmonary inflammation, fibrosis, apoptosis, and 4-hydroxynonenal density were evaluated by hematoxylin and eosin staining, Masson's trichrome staining, TUNEL staining, and immunohistochemistry. Hydroxyproline content and concentrations of inflammatory cytokines and oxidative stress markers were detected using corresponding kits. MRC-5 cells were treated with 10 ng/ml PDGF, and the effects of 1 mM sinomenine on cell proliferation were assessed by EdU assays. The mRNA expression of inflammatory cytokines and the protein levels of collagens, fibrosis markers, and key markers involved in the TLR4/NLRP3/TGFβ signaling were tested with RT-qPCR and immunoblotting analysis.

RESULTS

Sinomenine attenuated pulmonary fibrosis and inflammation while reducing hydroxyproline content and the protein expression of collagens and fibrosis markers in BLM-induced pulmonary fibrosis rats. Sinomenine reduced apoptosis in lung samples of BLM-challenged rats by increasing Bcl-2 and reducing Bax and cleaved caspase-3 protein expression. In addition, sinomenine alleviated inflammatory response and oxidative stress in rats with pulmonary fibrosis induced by BLM. Moreover, sinomenine inhibited the TLR4/NLRP3/TGFβ signaling pathway in lung tissues of BLM-stimulated rats. Furthermore, TLR4 inhibitor, TAK-242, attenuated PDGF-induced fibroblast proliferation and collagen synthesis in MRC-5 cells.

CONCLUSION

Sinomenine attenuates BLM-caused pulmonary fibrosis, inflammation, and oxidative stress by inhibiting the TLR4/NLRP3/TGFβ signaling, indicating that sinomenine might become a therapeutic candidate to treat pulmonary fibrosis.

Bioactivities and Mechanisms of Action of Sinomenine and Its Derivatives: A Comprehensive Review

Sinomenine, an isoquinoline alkaloid extracted from the roots and stems of Sinomenium acutum, has been extensively studied for its derivatives as bioactive agents. This review concentrates on the research advancements in the biological activities and action mechanisms of sinomenine-related compounds until November 2023. The findings indicate a broad spectrum of pharmacological effects, including antitumor, anti-inflammation, neuroprotection, and immunosuppressive properties. These compounds are notably effective against breast, lung, liver, and prostate cancers, exhibiting IC50 values of approximately 121.4 nM against PC-3 and DU-145 cells, primarily through the PI3K/Akt/mTOR, NF-κB, MAPK, and JAK/STAT signaling pathways. Additionally, they manifest anti-inflammatory and analgesic effects predominantly via the NF-κB, MAPK, and Nrf2 signaling pathways. Utilized in treating rheumatic arthritis, these alkaloids also play a significant role in cardiovascular and cerebrovascular protection, as well as organ protection through the NF-κB, Nrf2, MAPK, and PI3K/Akt/mTOR signaling pathways. This review concludes with perspectives and insights on this topic, highlighting the potential of sinomenine-related compounds in clinical applications and the development of medications derived from natural products.

Simultaneous determination of sinomenine and its metabolites desmethyl-sinomenine and sinomenine N-oxide in rat plasma by liquid chromatography tandem mass spectrometry

Sinomenine is an active ingredient extracted from herb medicine, which has been prescribed to treat rheumatoid arthritis in clinics. The present work was to develop a simple method to simultaneously determine sinomenine and its metabolites desmethyl sinomenine and sinomenine N-oxide in rat plasma by liquid chromatography tandem mass spectrometry. Precursor-to-product transitions for detection were m/z 330.2 > 239.1 for sinomenine, m/z 316.2 > 239.1 for desmethyl-sinomenine, m/z 346.2 > 314.1 for sinomenine N-oxide and m/z 286.2 > 153.2 for morphine (internal standard), respectively. During the validation and sample quantification, an excellent linear calibration range was observed for all the analytes with correlation coefficients more than 0.999 (r > 0.99). The extraction recovery was more than 85%. No significant matrix effect and carryover were observed. The precision was less than 6.45%, whereas accuracy ranged from -4.10% to 7.23%. The validated method has been successfully applied to the pharmacokinetic study of sinomenine, desmethyl sinomenine, and sinomenine N-oxide in rat plasma after oral administration of sinomenine at a single dose of 5 mg/kg. The results suggested that sinomenine was rapidly metabolized into its metabolite desmethyl sinomenine and sinomenine N-oxide.

Sinomenine improves renal fibrosis by regulating mesenchymal stem cell-derived exosomes and affecting autophagy levels

BACKGROUND

This study attempts to investigate the therapeutic effect of sinomenine on renal fibrosis and its mechanism.

METHODS

The 8-week-old C57BL/6 male mice were randomly divided into sham group, UUO model group, UUO sinomenine group (UUO + Sino 50), UUO + sinomenine group (UUO + Sino 100), UUO + exosome group (exo), and UUO + exo-inhibitor. The pathological changes of kidney were observed by H&E staining, the degree of renal interstitial fibrosis was detected by MASSON and Sirius red staining, and the expressions of fibrosis and autophagy markers were detected by real-time fluorescence quantitative PCR and WB. NTA and electron microscopy were used to analyze exo secretion after sinomenine treatment.

RESULTS

Sinomenine could improve the progression of renal fibrosis without causing tissue damage including heart, lungs and liver. Sinomenine could promote autophagosome formation. It could promote the secretion of exosomes from bone marrow mesenchymal stem cells (BMSCs). Sinomine regulates the PI3K-AKT pathway through BMSC-exo carrying miR-204-5p, affecting autophagy level and alleviating the process of renal fibrosis.

CONCLUSION

Our study suggests that sinomine could improve the progression of renal fibrosis by influencing the expression of miR-204-5p in BMSC-exo and regulating the PI3K-AKT pathway.

Functional Biomaterials for Local Control of Orthodontic Tooth Movement

Orthodontic tooth movement (OTM) occurs with the application of a controlled mechanical force and results in coordinated tissue resorption and formation in the surrounding bone and periodontal ligament. The turnover processes of the periodontal and bone tissue are associated with specific signaling factors, such as Receptor Activator of Nuclear factor Kappa-β Ligand (RANKL), osteoprotegerin, runt-related transcription factor 2 (RUNX2), etc., which can be regulated by different biomaterials, promoting or inhibiting bone remodeling during OTM. Different bone substitutes or bone regeneration materials have also been applied to repair alveolar bone defects followed by orthodontic treatment. Those bioengineered bone graft materials also change the local environment that may or may not affect OTM. This article aims to review functional biomaterials that were applied locally to accelerate OTM for a shorter duration of orthodontic treatment or impede OTM for retention purposes, as well as various alveolar bone graft materials which may affect OTM. This review article summarizes various types of biomaterials that can be locally applied to affect the process of OTM, along with their potential mechanisms of action and side effects. The functionalization of biomaterials can improve the solubility or intake of biomolecules, leading to better outcomes in terms of increasing or decreasing the speed of OTM. The ideal timing for initiating OTM is generally considered to be 8 weeks post-grafting. However, more evidence is needed from human studies to fully understand the effects of these biomaterials, including any potential adverse effects.

Full-length transcriptome and metabolite analysis reveal reticuline epimerase-independent pathways for benzylisoquinoline alkaloids biosynthesis in Sinomenium acutum

Benzylisoquinoline alkaloids (BIAs) are a large family of plant natural products with important pharmaceutical applications. Sinomenium acutum is a medicinal plant from the Menispermaceae family and has been used to treat rheumatoid arthritis for hundreds of years. Sinomenium acutum contains more than 50 BIAs, and sinomenine is a representative BIA from this plant. Sinomenine was found to have preventive and curative effects on opioid dependence. Despite the broad applications of S. acutum, investigation on the biosynthetic pathways of BIAs from S. acutum is limited. In this study, we comprehensively analyzed the transcriptome data and BIAs in the root, stem, leaf, and seed of S. acutum. Metabolic analysis showed a noticeable difference in BIA contents in different tissues. Based on the study of the full-length transcriptome, differentially expressed genes, and weighted gene co-expression network, we proposed the biosynthetic pathways for a few BIAs from S. acutum, such as sinomenine, magnoflorine, and tetrahydropalmatine, and screened candidate genes involved in these biosynthesis processes. Notably, the reticuline epimerase (REPI/STORR), which converts (S)-reticuline to (R)-reticuline and plays an essential role in morphine and codeine biosynthesis, was not found in the transcriptome data of S. acutum. Our results shed light on the biogenesis of the BIAs in S. acutum and may pave the way for the future development of this important medicinal plant.

Towards Better Sinomenine-Type Drugs to Treat Rheumatoid Arthritis: Molecular Mechanisms and Structural Modification

Sinomenine is the main component of the vine Sinomenium acutum. It was first isolated in the early 1920s and has since attracted special interest as a potential anti-rheumatoid arthritis (RA) agent, owing to its successful application in traditional Chinese medicine for the treatment of neuralgia and rheumatoid diseases. In the past few decades, significant advances have broadened our understanding of the molecular mechanisms through which sinomenine treats RA, as well as the structural modifications necessary for improved pharmacological activity. In this review, we summarize up-to-date reports on the pharmacological properties of sinomenine in RA treatment, document their underlying mechanisms, and provide an overview of promising sinomenine derivatives as potential RA drug therapies.

In vitro and Ex vivo Antioxidant Activity and Sustained Release Properties of Sinomenine-Loaded Liposomes-in-Hydrogel Biomaterials Simulating Cells-in-Extracellular Matrix

Sinomenine (SIN), a natural product, has been used to treat rheumatoid arthritis (RA) in China for thousands of years. SIN has been developed for the treatment of RA by way of tablets and injections, but both dosage forms have been associated with severe adverse reactions. Making SIN into liposomes-in-hydrogel biomaterials for external use has a good slow-release effect and can play an important role in avoiding the first-pass effect, gastrointestinal reaction, and increasing the local action time of drugs. SIN-loaded liposomes were formed by the thin-film dispersion method, then SIN-loaded liposomes-in-hydrogels were prepared by combining the SIN-L with hyaluronic acid (HA) hydrogels. In this paper, the basic characteristics, In vitro and Ex vivo release, and antioxidant activity of SIN-loaded liposomes-in-hydrogels were studied. The results showed that SIN-loaded liposomes-in-hydrogels have good sustained-release and antioxidant effects, and the preparation is expected to be a good biomaterial.

Potential therapeutic effects and pharmacological evidence of sinomenine in central nervous system disorders

Sinomenine is a natural compound extracted from the medicinal plant Sinomenium acutum. Its supplementation has been shown to present benefits in a variety of animal models of central nervous system (CNS) disorders, such as cerebral ischemia, intracerebral hemorrhage, traumatic brain injury (TBI), Alzheimer’s disease (AD), Parkinson’s disease (PD), epilepsy, depression, multiple sclerosis, morphine tolerance, and glioma. Therefore, sinomenine is now considered a potential agent for the prevention and/or treatment of CNS disorders. Mechanistic studies have shown that inhibition of oxidative stress, microglia- or astrocyte-mediated neuroinflammation, and neuronal apoptosis are common mechanisms for the neuroprotective effects of sinomenine. Other mechanisms, including activation of nuclear factor E2-related factor 2 (Nrf2), induction of autophagy in response to inhibition of protein kinase B (Akt)-mammalian target of rapamycin (mTOR), and activation of cyclic adenosine monophosphate-response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF), may also mediate the anti-glioma and neuroprotective effects of sinomenine. Sinomenine treatment has also been shown to enhance dopamine receptor D2 (DRD2)-mediated nuclear translocation of αB-crystallin (CRYAB) in astrocytes, thereby suppressing neuroinflammation via inhibition of Signal Transducer and Activator of Transcription 3 (STAT3). In addition, sinomenine supplementation can suppress N-methyl-D-aspartate (NMDA) receptor-mediated Ca²⁺ influx and induce γ-aminobutyric acid type A (GABA_A) receptor-mediated Cl⁻ influx, each of which contributes to the improvement of morphine dependence and sleep disturbance. In this review, we outline the pharmacological effects and possible mechanisms of sinomenine in CNS disorders to advance the development of sinomenine as a new drug for the treatment of CNS disorders.

Sinomenine Inhibits Orthodontic Tooth Movement and Root Resorption in Rats and Enhances Osteogenic Differentiation of PDLSCs

Purpose

To investigate the effects of sinomenine on orthodontic tooth movement and root resorption in rats, as well as the effect of sinomenine on the osteogenesis of periodontal ligament stem cells (PDLSCs).

Methods

Fifty-four male Wistar rats were randomly divided into 3 groups: control group, 20 mg/kg sinomenine group and 40 mg/kg sinomenine group. Fifty-gram orthodontic force was applied to all groups. Each group was injected intraperitoneally with corresponding concentration of sinomenine every day. After 14 days, all rats were sacrificed. Micro-computed tomography (micro-CT) scan was used to analyze tooth movement, root resorption and alveolar bone changes. The effect on periodontal tissue was analyzed by Masson, tartrate-resistant acid phosphatase (TRAP) and immunohistochemical staining. In vitro, PDLSCs were extracted and identified. The effect of sinomenine on proliferation was determined by cell-counting kit-8. The effect of sinomenine on osteogenesis was investigated by alkaline phosphatase (ALP) activity and alizarin red staining. qPCR and Western blotting were performed to explore the effects of sinomenine on the expression levels of ALP, runt-related transcription factor 2 (RUNX2), receptor activator of nuclear factor kappaB ligand (RANKL) and osteoprotegerin (OPG).

Results

The tooth movement and root resorption of sinomenine groups were reduced. Sinomenine decreased trabecular spacing on compression side and increased alveolar bone volume and trabecular thickness on tension side. TRAP-positive cells in sinomenine groups decreased significantly. The expressions of TNF-α and RANKL were decreased, while the expressions of OPG, RUNX2 and osteocalcin were up-regulated. In vitro, 0.1 M and 0.5 M sinomenine enhanced ALP activity, mineral deposition and the expression of ALP, RUNX2 and OPG, and reduced the expression of RANKL.

Conclusion

Sinomenine could inhibit tooth movement, reduce root resorption, and exert a positive effect on bone formation in rats. Moreover, sinomenine promoted the osteogenesis of PDLSCs.

Evaluating the cardioprotective effect of metformin on myocardial ischemia-reperfusion injury using dynamic 18F-FDG micro-PET/CT imaging

BACKGROUND

The molecular mechanisms of protective effect of metformin (Met) on ischemic myocardium have not been fully understood. This study aims to evaluate the cardioprotective effect of metformin on myocardial ischemia-reperfusion injury (MIRI) in rat models at different time points using dynamic 18F-FDG micro-PET/CT imaging.

METHODS

The I/R injury model in SD rats was established by ligation of left anterior descending coronary artery near the pulmonary arch root for 30 min. SD rats (n = 12) were randomly divided into 2 groups: Control group (n = 6) without any intervention and Met group (n = 6) with oral administration of metformin (50 mg/kg) twice a day. Gated 18F-FDG (40Mbq) micro-PET/CT imaging was performed for 10 min at different time points (day 1st, day 7th, day 14th and day 30th after operation). Volumes of interest were drawn to identify different myocardium regions (ischemia center, peri-ischemia area and remote area). Standardized uptake values (SUVs) (SUVmean and SUVmax) were analyzed to evaluate the FDG uptake activity, and then the center/remote ratio was calculated. In addition, the left ventricular (LV) end-diastolic volume (EDV), end-systolic volume (ESV) and LV ejection fraction (LVEF) were obtained. On the 30th day, all rats were scarified and myocardial ischemia was analyzed by HE staining and confirmed by pathology.

RESULTS

In the Control group, the center/remote ratio showed no obvious change trend at each time point after reperfusion, while the LV EDV increased gradually over time, and they were significantly negatively correlated (r = - 0.507, p < 0.05). In the Met group, the center/remote ratio gradually increased with time, there was no significant correlation between center/remote ratio and LV EDV (r = - 0.078, p > 0.05). On the 30th day, the center/remote ratio of the Met group was significantly higher than that of the Control group (0.81 ± 0.06 vs. 0.65 ± 0.09, p < 0.05), while LV EDV in Met group was significantly lower than in Control group (358.21 ± 22.62 vs. 457.53 ± 29.91, p < 0.05). There was no significant difference of LVEF between Met group and Control group at different time points after reperfusion (p < 0.05). HE staining showed that the myocardial infarction and fibrosis in ischemic center area of the Control group was more serious than that of the Met group.

CONCLUSIONS

Met could attenuate the severity of MIRI, delay and prevent the progress of LV remodeling. The cardioprotective progress could be dynamically assessed by 18F-FDG micro-PET/CT imaging.

Sinomenine Confers Protection Against Myocardial Ischemia Reperfusion Injury by Preventing Oxidative Stress, Cellular Apoptosis, and Inflammation

Sinomenine (SIN), an alkaloid extracted from the root of S. acutum. sinomenine, has been shown to have antiarrhythmic, antioxidant, and anti-inflammatory effects in myocardial ischemia-reperfusion injury (MIRI) ex vivo. In this study, we investigated the cardioprotective effects of SIN in an in vivo mouse model of MIRI. Adult male C57BL/6J mice received SIN (80 mg/kg) for 5 days and underwent 30 min of percutaneous occlusion of the left anterior descending artery (LAD) followed by 24 h of reperfusion. Results showed that pretreatment with SIN significantly reduced myocardial infarct size and concentrations of markers of cardiac injury and improved left ventricular ejection fraction (EF) and shortening fraction (FS) in MIRI mice. The SIN pretreatment prevented the MIRI-induced decrease in the expression levels of Bcl-2, increase in the expression levels of caspase-3, caspase-9, and Bax, and increase in the number of TUNEL-positive cells in ischemic heart tissue. It was also found that pretreatment with SIN prevented the MIRI-induced oxidative stress imbalance in ischemic heart tissue, as shown by the increase in total antioxidant capacity (T-AOC) and glutathione (GSH) and the decrease in malondialdehyde (MDA), reactive oxygen species (ROS), and dihydroethidium (DHE) density. Further studies showed that the stimulus of cardiac ischemia/reperfusion caused a remarkable increase in the expression levels of interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) mRNA in ischemic heart tissue, which was effectively prevented by pretreatment with SIN. These results demonstrate that SIN can attenuate MIRI-induced cardiac injury in vivo by preventing oxidative stress, inflammation, and apoptosis.

The mechanism of microglia-mediated immune inflammation in ischemic stroke and the role of natural botanical components in regulating microglia: A review

Ischemic stroke (IS) is one of the most fatal diseases. Neuroimmunity, inflammation, and oxidative stress play important roles in various complex mechanisms of IS. In particular, the early proinflammatory response resulting from the overactivation of resident microglia and the infiltration of circulating monocytes and macrophages in the brain after cerebral ischemia leads to secondary brain injury. Microglia are innate immune cells in the brain that constantly monitor the brain microenvironment under normal conditions. Once ischemia occurs, microglia are activated to produce dual effects of neurotoxicity and neuroprotection, and the balance of the two effects determines the fate of damaged neurons. The activation of microglia is defined as the classical activation (M1 type) or alternative activation (M2 type). M1 type microglia secrete pro-inflammatory cytokines and neurotoxic mediators to exacerbate neuronal damage, while M2 type microglia promote a repairing anti-inflammatory response. Fine regulation of M1/M2 microglial activation to minimize damage and maximize protection has important therapeutic value. This review focuses on the interaction between M1/M2 microglia and other immune cells involved in the regulation of IS phenotypic characteristics, and the mechanism of natural plant components regulating microglia after IS, providing novel candidate drugs for regulating microglial balance and IS drug development.