Novel mechanistic insight on the neuroprotective effect of berberine: The role of PPARδ for antioxidant action

Substance basis and pharmacological mechanism of heat-clearing herbs in the treatment of ischaemic encephalopathy: a systematic review and network pharmacology

BACKGROUND AND OBJECTIVE

Ischaemic encephalopathy is a common cerebrovascular disease caused by insufficient blood supply to the cerebral vessels. The ischaemic encephalopathy is closely associated with the development of many chronic diseases such as obesity, hypertension and diabetes. Neurotrophic therapy has become the main therapeutic strategy for ischaemic encephalopathy. However, neurotrophic drugs only slightly recover the neurological function of patients, and their long-term efficacy is uncertain. Previous reports revealed that the active ingredients of natural medicines play important roles in the treatment of cerebral ischemia. In this study, we reviewed clearing herbs with anti-ischaemic encephalopathy functions using the data from quantitative statistical and network pharmacological exploration methods. We also discussed the different bioactive components and pharmacological effects of these herbs.

METHODS

First, we collected Chinese herbal prescriptions against ischaemic encephalopathy in four databases. Then, we statistically analysed the frequency of application of heat-clearing herbs to obtain the commonly used heat-clearing herbs against ischaemic encephalopathy, and classified them according to their efficacy according to the statistical results, to summarize the mechanism of anti-ischaemic effects of different bioactive components; Second, the network database was used to obtain the above components of heat-clearing Chinese medicines and their corresponding targets of action, disease targets of ischaemic stroke; Venny 2.1.0 was used to obtain component-disease target intersections; Cytoscape was used to construct the 'Drug-Active Ingredient-Target Network Graph '; DAVID was used for GO and KEGG enrichment analysis.

RESULTS

Literature and database screening involved 149 prescriptions, with a total of 269 flavours of Chinese medicines and 20 flavours of single-flavour heat-clearing Chinese medicines; The top nine in terms of frequency of use were Radix Paeoniae Rubra、Rehmanniae Radix Praeparata、Figwort Root、Cortex Moutan、Scutellariae Radix、Coptidis Rhizoma、Gardeniae Fructus、Cassiae Semen、Lonicerae Japonicae Flos. The common components obtained from network pharmacology were beta-sitosterol, quercetin, and stigmasterol, which mainly act on key targets such as RELA, AKT1, JUN, PRKACA, PTGS2, RAF1 and CHUK; and their active ingredients are mainly involved in signalling pathways such as Calcium, PI3K-Ak, MAPK, cAMP, IL-17, HIF-1, TNF, T-cell receptor, NF-kappa B and JAK-STAT.

CONCLUSIONS

Heat-clearing herbs are useful and promising for the protection against and prevention of ischemic encephalopathy. The results of the network pharmacological studies are similar to the mechanisms of anti-ischemic encephalopathy of the active ingredients of the purgative herbs we have listed; Thin either directly protects cerebrovascular tissues by improving vascular permeability and reducing the area of infarcted tissues, or produces protective effects through molecular signaling pathways. It can be seen that the components of heat-clearing Chinese medicines can exert cerebroprotective effects through multiple pathways, which provides us with a reference for further development and study of heat-clearing Chinese medicines in the treatment of ischemic cerebrovascular diseases.

Neuroprotective effect and preparation methods of berberine

Berberine (BBR) is a natural alkaloid, which has played an important role in the field of medicine since its discovery in the late 19th century. However, the low availability of BBR in vivo prevents its full effect. In recent years, a large number of studies confirmed that BBR has a protective effect on the nervous system through various functions, yet the issue of the inability to systematically understand the protection of BBR on the nervous system remains a gap that needs to be addressed. Many existing literature introductions about berberine in neurodegenerative diseases, but the role of berberine in the nervous system goes far beyond these. Different from these literatures, this review is divided into three parts: preparation method, mechanism, and therapeutic effect. Various dosage forms of BBR and their preparation methods are added, in order to provide a reasonable choice of BBR, and help to solve the problem of low bioavailability in treatment. More importantly, we more comprehensively summarize the mechanism of BBR to protect the nervous system, in addition to the treatment of neurodegenerative diseases (anti-oxidative stress, anti-neuroinflammation, regulation of apoptosis), two extra mechanisms of berberine for the protection of the nervous system were also introduced: bidirectional regulation of autophagy and promote angiogenesis. Also, we have clarified the precise mechanism by which BBR has a therapeutic effect not only on neurodegenerative illnesses but also on multiple sclerosis, gliomas, epilepsy, and other neurological conditions. To sum up, we hope that these can evoke more efforts to comprehensively utilize of BBR nervous system, and to promote the application of BBR in nervous system protection.

Prepubertal Repeated Berberine Supplementation Enhances Cerebrocerebellar Functions by Modulating Neurochemical and Behavioural Changes in Wistar Rats

Antioxidant-rich supplementation plays an essential role in the function of mammals' central nervous system. However, no research has documented the effect of berberine (BER) supplementation on the cerebrocerebellar function of prepubertal rats. The present study was designed to investigate the impact of BER supplementation on neurochemical and behavioural changes in prepubertal male rats. Five groups (90 ± 5 g, n = 7 each) of experimental rats were orally treated with corn oil or different doses of BER (25, 50, 100, and 200 mg/kg bw) from the 28th at 68 post-natal days. On the 69 days of life, animals underwent behavioural assessment in the open field, hanging wire, and negative geotaxis tests. The result revealed that BER administration improved locomotive and motor behaviour by increasing distance travelled, line crossings, average speed, time mobile, and absolute turn angle in open field test and decrease in time to re-orient on an incline plane, a decrease in immobility time relative to the untreated control. Furthermore, BER supplementation increased (p < 0.05) antioxidant enzyme activities such as SOD, CAT, GPx, GSH, and TSH and prevented increases (p < 0.05) in oxidative and inflammatory levels as indicated by decreases in RONS, LPO, XO, carbonyl protein, NO, MPO, and TNF-α compared to the untreated control. BER-treated animals a lessened number of dark-stained Nissl cells compared to the untreated control rats. Our findings revealed that BER minimised neuronal degeneration and lesions, improved animal behaviour, and suppressed oxidative and inflammatory mediators, which may probably occur through its agonistic effect on PPAR-α, PPAR-δ, and PPAR-γ - essential proteins known to resolve inflammation and modulate redox signalling towards antioxidant function.

Effect of berberine on the hippocampal structure, biochemical factors, memory, and blood-brain barrier in rat model of transient global cerebral ischemia

Global cerebral ischemia (GCI) results in damage to the neurons and leads to cognitive impairments. Berberine (BBR) is known for its neuroprotective qualities. This study aimed to investigate the effects of BBR on memory, Blood-brain barrier (BBB) permeability, biochemical factors, and neuronal structure. Sixty-three adult male Wistar rats were divided randomly into Sham (21), GCI (21), and GCI + BBR (21) groups. The GCI + BBR group received 50 mg/kg of BBR for 7 days before and 6 h after 20 min of GCI induction. After 24 h, assessments included hippocampal neuronal structure, catalase (CAT), superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GPX) levels, memory performance, and BBB permeability. The GCI + BBR group reduced volume loss in the CA1 and its sublayers (oriens, pyramidal, and radiatum) compared to the GCI group (p < 0.0001, p < 0.001, p < 0.01 and p < 0.001, respectively). Additionally, the GCI + BBR group showed higher pyramidal neuron density (p < 0.0001) and number (p < 0.0001) compared to the GCI group. BBR also decreased MDA levels (p < 0.0001) and increased CAT activity (p < 0.0001) in the GCI + BBR group compared to the GCI group, with GPX and SOD activity approaching Sham levels (p < 0.0001, both). BBR demonstrated significant improvements in short and long-term memory compared to the GCI group (p < 0.01, p < 0.0001, respectively). Furthermore, BBB permeability in the GCI + BBR group was significantly reduced compared to the GCI group (p < 0.0001). These findings demonstrated BBR's potential to protect the neurons in the CA1 and BBB structures, enhance antioxidant activity, and alleviate GCI-induced memory impairments.

Supersaturated Drug Delivery System of Oxyberberine Based on Cyclodextrin Nanoaggregates: Preparation, Characterization, and in vivo Application

Propose

Oxyberberine (OBB), one of the main metabolites of berberine derived from intestinal and erythrocyte metabolism, exhibits appreciable anti-hyperuricemic activity. However, the low water solubility and poor plasma concentration-effect relationship of OBB hamper its development and utilization. Therefore, an OBB-hydroxypropyl-β-cyclodextrin (HP-β-CD) supersaturated drug delivery system (SDDS) was prepared and characterized in this work.

Methods

OBB-HP-β-CD SDDS was prepared using the ultrasonic-solvent evaporation method and characterized. Additionally, the in vitro and in vivo release experiments were conducted to assess the release kinetics of OBB-HP-β-CD SDDS. Subsequently, the therapeutic efficacy of OBB-HP-β-CD SDDS on hyperuricemia (HUA) was investigated by means of histopathological examination and evaluation of relevant biomarkers.

Results

The results of FT-IR, DSC, PXRD, NMR and molecular modeling showed that the crystallized form of OBB was transformed into an amorphous OBB-HP-β-CD complex. Dynamic light scattering indicated that this system was relatively stable and maintained by formation of nanoaggregates with an average diameter of 23 nm. The dissolution rate of OBB-HP-β-CD SDDS was about 5 times higher than that of OBB raw material. Furthermore, the AUC0-t of OBB-HP-β-CD SDDS (10.882 μg/mL*h) was significantly higher than that of the raw OBB counterpart (0.701 μg/mL*h). The oral relative bioavailability of OBB-HP-β-CD SDDS was also enhanced by 16 times compared to that of the raw material. Finally, in vivo pharmacodynamic assay showed the anti-hyperuricemic potency of OBB-HP-β-CD SDDS was approximately 5-10 times higher than that of OBB raw material.

Conclusion

Based on our findings above, OBB-HP-β-CD SDDS proved to be an excellent drug delivery system for increasing the solubility, dissolution, bioavailability, and anti-hyperuricemic potency of OBB.

Isolation of a novel isoprenylated phenolic compound and neuroprotective evaluation of Dodonaea viscosa extract against cerebral ischaemia-reperfusion injury in rats

Dodonaea viscosa grows widely in Saudi Arabia, but studies evaluating its neuroprotective activity are lacking. Thus, this study aimed to isolate and identify the secondary metabolites and evaluate the neuroprotective effects of D. viscosa leaves. The isolation and identification of phytochemicals were performed using chromatographic and spectroscopic techniques. The neuroprotective potential of the extract was evaluated against focal cerebral ischaemia-reperfusion injury in rat model. Neurobehavioural deficits in the rats were evaluated, and their brains were harvested to measure infarct volume and oxidative biomarkers. Results revealed the presence of three compounds: a novel isoprenylated phenolic derivative that was elucidated as 4-hydroxy-3-(3'-methyl-2'-butenyl) phenyl 1-O-β-D-apiosyl-(1''' → 6'')- β-D-glucopyranoside (named Viscomarfadol) and two known compounds (isorhamnetin-3-O-rutinoside and epicatechin (4-8) catechin). Pre-treatment of the rats with the extract improved neurological outcomes. It significantly reduced neurological deficits and infarct volume; significantly reduced lipid peroxidation, as evidenced by decreased malondialdehyde levels; and significantly elevated antioxidant (superoxide dismutase, catalase, and glutathione) activities. These results indicate that D. viscosa is a promising source of bioactive compounds that can improve neurological status, decrease infarct volume, and enhance antioxidant activities in rats with cerebral ischaemic injury. Thus, D. viscosa could be developed into an adjuvant therapy for ischaemic stroke and other oxidative stress-related neurodegenerative disorders. Further investigations are warranted to explore other bioactive compounds in D. viscosa and evaluate their potential neuroprotective activities.

Investigation of Antioxidant and Anti-inflammatory Properties of Berberine Nanomicelles: In vitro and In vivo Studies

INTRODUCTION

In the present study, neuroprotective effects of berberine (BBR) and berberine nanomicelle (BBR-NM) against lipopolysaccharides (LPS)-induced stress oxidative were investigated, and compared by evaluating their antioxidant and anti-inflammatory activities in PC12 cells, and rat brains. A fast, green, and simple synthesis method was used to prepare BBR-NMs.

METHOD

The prepared BBR-NMs were then characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). In vitro experiments were carried out on the LPS-treated PC12 cell lines to investigate the anti-cytotoxic and antioxidant properties of BBR-NM and BBR. The results showed that BBR-NMs with a diameter of ~100 nm had higher protective effects against ROS production and cytotoxicity induced by LPS in PC12 cells in comparison with free BBR.

RESULTS

Moreover, in vivo experiments indicated that the activity levels of antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), increased in the brain of LPS-treated rats administrated with BBR-NM at the optimum dose of 100 mg.kg-1. BBR-NM administration also resulted in decreased concentration of lipid peroxidation (MDA) and pro-inflammatory cytokines, such as Serum interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α).

CONCLUSION

Overall, BBR-NM demonstrated higher neuroprotective effects than free BBR, making it a promising treatment for improving many diseases caused by oxidative stress and inflammation.

Neuroprotective Properties of Berberine: Molecular Mechanisms and Clinical Implications

Berberine (BBR), an isoquinoline alkaloid natural product, is isolated primarily from Coptis chinensis and other Berberis plants. BBR possesses various bioactivities, including antioxidant, anti-inflammation, anticancer, immune-regulation, and antimicrobial activities. Growing scientific evidence underscores BBR's substantial neuroprotective potential, prompting increased interest and scrutiny. In this comprehensive review, we elucidate the neuroprotective attributes of BBR, delineate the underlying molecular mechanisms, and assess its clinical safety and efficacy. The multifaceted molecular mechanisms responsible for BBR's neuroprotection encompass the attenuation of oxidative stress, mitigation of inflammatory responses, inhibition of apoptotic pathways, facilitation of autophagic processes, and modulation of CYP450 enzyme activities, neurotransmitter levels, and gut microbiota composition. Furthermore, BBR engages numerous signaling pathways, including the PI3K/Akt, NF-κB, AMPK, CREB, Nrf2, and MAPK pathways, to confer its neuroprotective effects. This comprehensive review aims to provide a substantial knowledge base, stimulate broader scientific discourse, and facilitate advancements in the application of BBR for neuroprotection.

Role of traditional Chinese medicine monomers in cerebral ischemia/reperfusion injury:a review of the mechanism

Ischemia/reperfusion (I/R) injury is a pathological process wherein reperfusion of an ischemic organ or tissue exacerbates the injury, posing a significant health threat and economic burden to patients and their families. I/R triggers a multitude of physiological and pathological events, such as inflammatory responses, oxidative stress, neuronal cell death, and disruption of the blood-brain barrier (BBB). Hence, the development of effective therapeutic strategies targeting the pathological processes resulting from I/R is crucial for the rehabilitation and long-term enhancement of the quality of life in patients with cerebral ischemia/reperfusion injury (CIRI). Traditional Chinese medicine (TCM) monomers refer to bioactive compounds extracted from Chinese herbal medicine, possessing anti-inflammatory and antioxidative effects, and the ability to modulate programmed cell death (PCD). TCM monomers have emerged as promising candidates for the treatment of CIRI and its subsequent complications. Preclinical studies have demonstrated that TCM monomers can enhance the recovery of neurological function following CIRI by mitigating oxidative stress, suppressing inflammatory responses, reducing neuronal cell death and functional impairment, as well as minimizing cerebral infarction volume. The neuroprotective effects of TCM monomers on CIRI have been extensively investigated, and a comprehensive understanding of their mechanisms can pave the way for novel approaches to I/R treatment. This review aims to update and summarize evidence of the protective effects of TCMs in CIRI, with a focus on their role in modulating oxidative stress, inflammation, PCD, glutamate excitotoxicity, Ca2+ overload, as well as promoting blood-brain barrier repairment and angiogenesis. The main objective is to underscore the significant contribution of TCM monomers in alleviating CIRI.

Berberine Reduces Lipid Accumulation in Obesity via Mediating Transcriptional Function of PPARδ

Obesity is defined as a dampness-heat syndrome in traditional Chinese medicine. Coptidis Rhizoma is an herb used to clear heat and eliminate dampness in obesity and its complications. Berberine (BBR), the main active compound in Coptidis Rhizoma, shows anti-obesity effects. Peroxisome proliferator-activated receptors (PPARs) are a group of nuclear receptor proteins that regulate the expression of genes involved in energy metabolism, lipid metabolism, inflammation, and adipogenesis. However, whether PPARs are involved in the anti-obesity effect of BBR remains unclear. As such, the aim of this study was to elucidate the role of PPARs in BBR treatment on obesity and the underlying molecular mechanisms. Our data showed that BBR produced a dose-dependent regulation of the levels of PPARγ and PPARδ but not PPARα. The results of gene silencing and specific antagonist treatment demonstrated that PPARδ is key to the effect of BBR. In 3T3L1 preadipocytes, BBR reduced lipid accumulation; in high-fat-diet (HFD)-induced obese mice, BBR reduced weight gain and white adipose tissue mass and corrected the disturbed biochemical parameters, including lipid levels and inflammatory and oxidative markers. Both the in vitro and in vivo efficacies of BBR were reversed by the presence of a specific antagonist of PPARδ. The results of a mechanistic study revealed that BBR could activate PPARδ in both 3T3L1 cells and HFD mice, as evidenced by the significant upregulation of PPARδ endogenous downstream genes. After activating by BBR, the transcriptional functions of PPARδ were invoked, exhibiting negative regulation of CCAAT/enhancer-binding protein α (Cebpα) and Pparγ promoters and positive mediation of heme oxygenase-1 (Ho-1) promoter. In summary, this is the first report of a novel anti-obesity mechanism of BBR, which was achieved through the PPARδ-dependent reduction in lipid accumulation.

Astrocytes-derived exosomes pre-treated by berberine inhibit neuroinflammation after stroke via miR-182-5p/Rac1 pathway

BACKGROUND

Our previous studies have shown that berberine can improve the nerve function deficits in ischemic stroke by inhibiting inflammation. The cellular communication between astrocytes and neurons via exosomes might affect neurological function after ischemic stroke, which plays a vital role in the therapy of ischemic stroke.

OBJECTIVE

The present study focused on the effects of exosomes released from astrocytes induced by the glucose and oxygen deprivation model with berberine pretreatment (BBR-exos) treatment for ischemic stroke and its regulatory mechanism.

METHODS

Oxygen-glucose-deprivation/Reoxygenation (OGD/R)-treated primary cells were used to mimic cerebral ischemia/reperfusion conditions in vitro. With the treatment of BBR-exos and exosomes released from primary astrocytes induced by the glucose and oxygen deprivation model (OGD/R-exos), the cell viability was detected. C57BL/6J mice were used to establish middle cerebral artery occlusion/reperfusion (MCAO/R) model. The anti-neuroinflammation effects of BBR-exos and OGD/R-exos were evaluated. Subsequently, the key miRNA in BBR-exos was identified by exosomal miRNA sequencing and cell validation. miR-182-5p mimic and inhibitors were provided to verify the effects in inflammation. Finally, the binding sites between miR-182-5p and Rac1 were predicted online and verified by using a dual-luciferase reporter assay.

RESULTS

BBR-exos and OGD/R-exos both improved the decreased activity of OGD/R-induced neurons, and decreased the expression of IL-1β, IL-6 and TNF-α (all P ＜ 0.05), which reduced neuronal injury and inhibited neuroinflammation in Vitro. And BBR-exos showed better effects (P ＜ 0.05). The same effect has been verified in vivo experiments: BBR-exos and OGD/R-exos both reduced cerebral ischemic injury and inhibited neuroinflammation in MCAO/R mice (all P ＜ 0.05). Likewise, BBR-exos showed better effects (P ＜ 0.05). The exosomal miRNA sequencing results showed that miR-182-5p was highly expressed in BBR-exos and inhibited neuroinflammation by targeting Rac1 (P ＜ 0.05).

CONCLUSION

BBR-exos can carry miR-182-5p to injured neurons and inhibit the expression of Rac1, which could inhibit neuroinflammation and improved brain injury after ischemic stroke.

Berberine activates PPARδ and promotes gut microbiota-derived butyric acid to suppress hepatocellular carcinoma

BACKGROUND

Peroxisome proliferator-activated receptors (PPARs) are a family of ligand-inducible transcription factors that govern various essential metabolic activities in the liver and other organs. Recently, berberine (BBR) has been characterized as a modulator of PPARs; however, the matter of whether PPARs are involved in the inhibitory effect of BBR on hepatocellular carcinoma (HCC) is not well understood.

PURPOSE

This study aimed to investigate the role of PPARs in the suppressive effect of BBR on HCC and to elucidate the relative mechanism.

METHODS

We studied the role of PPARs in the anti-HCC effects of BBR both in vitro and in vivo. The mechanism whereby BBR regulated PPARs was studied using real-time PCR, immunoblotting, immunostaining, luciferase, and a chromatin immunoprecipitation coupled PCR assay. Additionally, we used adeno-associated virus (AAV)-mediated gene knockdown to address the effect of BBR more effectively.

RESULTS

We demonstrated that PPARδ played an active role in the anti-HCC effect of BBR, rather than PPARα or PPARγ. Following a PPARδ-dependent manner, BBR increased BAX, cleaved Caspase 3, and decreased BCL2 expression to trigger apoptotic death, thereby suppressing HCC development both in vitro and in vivo. It was noted that the interactions between PPARδ and the apoptotic pathway resulted from the BBR-induced upregulation of the PPARδ transcriptional function; that is, the BBR-induced activation of PPARδ could mediate the binding with the promoters of apoptotic genes such as Caspase 3, BAX, and BCL2. Moreover, gut microbiota also contributed to the suppressive effect of BBR on HCC. We found that BBR treatment restored the dysregulated gut microbiota induced by the liver tumor burden, and a functional gut microbial metabolite, butyric acid (BA), acted as a messenger in the gut microbiota-liver axis. Unlike BBR, the effects of BA suppressing HCC and activating PPARδ were not potent. However, BA was able to enhance the efficacy of BBR by reducing PPARδ degradation through a mechanism to inhibit the proteasome ubiquitin system. Additionally, we found that the anti-HCC effect of BBR or a combination of BBR and BA was much weaker in mice with AAV-mediated PPARδ knockdown than those in the control mice, suggesting the critical role of PPARδ.

CONCLUSION

In summary, this study is the first to report that a liver-gut microbiota-PPARδ trilogy contributes to the anti-HCC effect of BBR. BBR not only directly activated PPARδ to trigger apoptotic death but also promoted gut microbiota-derived BA production, which could reduce PPARδ degradation to enhance the efficacy of BBR.

Advances of berberine against metabolic syndrome-associated kidney disease: Regarding effect and mechanism

The prevalence of metabolic syndrome (MetS) is drastically growing worldwide, resulting in MetS-associated kidney disease. According to traditional theories, preventing blood pressure, lipid, glycose, and obesity and improving insulin resistance (IR), a couple of medications are required for MetS. It not only lowers patients' compliance but also elevates adverse reactions. Accordingly, we attempted to seek answers from complementary and alternative medicine. Ultimately, berberine (BBR) was chosen due to its efficacy and safety on MetS through multi-pathways and multi-targets. The effects and mechanisms of BBR on obesity, IR, diabetic nephropathy, hypertension, hyperlipidemia, and hyperuricemia were elaborated. In addition, the overall properties of BBR and interventions for various kidney diseases were also collected. However, more clinical trials are expected to further identify the beneficial effects of BBR.

Pharmacokinetic of berberine, the main constituent of Berberis vulgaris L.: A comprehensive review

Barberry (Berberis vulgaris L.) is a medicinal plant and its main constituent is an isoquinoline alkaloid named berberine that has multiple pharmacological effects such as antioxidant, anti-microbial, antiinflammatory, anticancer, anti-diabetes, anti-dyslipidemia, and anti-obesity. However, it has restricted clinical uses due to its very poor solubility and bioavailability (less than 1%). It undergoes demethylenation, reduction, and cleavage of the dioxymethylene group in the first phase of metabolism. Its phase two reactions include glucuronidation, sulfation, and methylation. The liver is the main site for berberine distribution. Berberine could excrete in feces, urine, and bile. Fecal excretion of berberine (11-23%) is higher than urinary and biliary excretion routes. However, a major berberine metabolite is excreted in urine greater than in feces. Concomitant administration of berberine with other drugs such as metformin, cyclosporine A, digoxin, etc. may result in important interactions. Thus, in this review, we gathered and dissected any related animal and human research articles regarding the pharmacokinetic parameters of berberine including bioavailability, metabolism, distribution, excretion, and drug-drug interactions. Also, we discussed and gathered various animal and human studies regarding the developed products of berberine with better bioavailability and consequently, better therapeutic effects.

The Role of Concomitant Nrf2 Targeting and Stem Cell Therapy in Cerebrovascular Disease

Despite the reality that a death from cerebrovascular accident occurs every 3.5 min in the United States, there are few therapeutic options which are typically limited to a narrow window of opportunity in time for damage mitigation and recovery. Novel therapies have targeted pathological processes secondary to the initial insult, such as oxidative damage and peripheral inflammation. One of the greatest challenges to therapy is the frequently permanent damage within the CNS, attributed to a lack of sufficient neurogenesis. Thus, recent use of cell-based therapies for stroke have shown promising results. Unfortunately, stroke-induced inflammatory and oxidative damage limit the therapeutic potential of these stem cells. Nuclear factor erythroid 2-related factor 2 (Nrf2) has been implicated in endogenous antioxidant and anti-inflammatory activity, thus presenting an attractive target for novel therapeutics to enhance stem cell therapy and promote neurogenesis. This review assesses the current literature on the concomitant use of stem cell therapy and Nrf2 targeting via pharmaceutical and natural agents, highlighting the need to elucidate both upstream and downstream pathways in optimizing Nrf2 treatments in the setting of cerebrovascular disease.

Therapeutic Efficacies of Berberine against Neurological Disorders: An Update of Pharmacological Effects and Mechanisms

Neurological disorders are ranked as the leading cause of disability and the second leading cause of death worldwide, underscoring an urgent necessity to develop novel pharmacotherapies. Berberine (BBR) is a well-known phytochemical isolated from a number of medicinal herbs. BBR has attracted much interest for its broad range of pharmacological actions in treating and/or managing neurological disorders. The discoveries in basic and clinical studies of the effects of BBR on neurological disorders in the last decade have provided novel evidence to support the potential therapeutical efficacies of BBR in treating neurological diseases. In this review, we summarized the pharmacological properties and therapeutic applications of BBR against neurological disorders in the last decade. We also emphasized the major pathways modulated by BBR, which provides firm evidence for BBR as a promising drug candidate for neurological disorders.