Effects of berberine on matrix accumulation and NF-kappa B signal pathway in alloxan-induced diabetic mice with renal injury

The Application of Berberine in Fibrosis and the Related Diseases

The formation of fibrotic tissue, characterized by the excessive accumulation of extracellular matrix (ECM) components such as collagen and fibronectin, is a normal and crucial stage of tissue repair in all organs. The over-synthesis, deposition, and remodeling of ECM components lead to organ dysfunction, posing a significant medical burden. Berberine, an isoquinoline alkaloid, is commonly used in the treatment of gastrointestinal diseases. With the deepening of scientific research, it has been gradually discovered that berberine also plays an important role in fibrotic diseases. In this review, we systematically introduce the effective role of berberine in fibrosis-related diseases. Specifically, this paper aims to provide a comprehensive review of the therapeutic role of berberine in treating fibrosis in organs such as the heart, liver, lungs, and kidneys. By summarizing its various pathways and mechanisms of action, including the inhibition of the transforming growth factor-[Formula: see text]/Smad signaling pathway, PI3K/Akt signaling pathway, MAPK signaling pathway, RhoA/ROCK signaling, and mTOR/p70S6K signaling pathway, as well as its activation of the Nrf2-ARE signaling pathway, AMPK signaling pathway, phosphorylated Smad 2/3 and Smad 7, and other signaling pathways, this review offers additional evidence to support the treatment of fibrotic diseases.

Berberine alleviates chlorpyrifos-induced nephrotoxicity in rats via modulation of Nrf2/HO-1 axis

Chlorpyrifos (CPS), an organophosphorus insecticide, is widely used for agricultural and non-agricultural purposes with hazardous health effects. Berberine (BBR) is a traditional Chinese medicine and a phytochemical with anti-inflammatory and anti-oxidative properties. The present study evaluated the effects of BBR against kidney damage induced by CPS and the underlying mechanisms. An initial study indicated that BBR 50 mg/kg was optimal under our experimental conditions. Then, 24 rats (6/group) were randomized into: control, BBR (50 mg/kg/day), CPS (10 mg/kg/day), and CPS + BBR. BBR was administration 1 h prior to CPS. Each treatment was delivered daily for a period of 28 consecutive days using a gastric gavage tube. Compared to CPS-alone treated rats, BBR effectively improved renal function by preventing the rise in serum urea, creatinine, and uric levels. The reno-protective effects of BBR were confirmed through a histological examination of kidney tissues. BBR restored oxidant-antioxidant balance in renal tissues mediated by Keap1/Nrf2/HO-1 axis modulation. In addition, BBR decreased nitric oxide (NO) and myeloperoxidase (MPO) activity. This was paralleled with the potent down-regulation of NF-κB. Furthermore, BBR exhibited anti-apoptotic activities supported by the upregulation of Bcl-2 and down-regulation of Bax and caspase-3 expression. In conclusion, our data suggest that BBR attenuates CPS-induced nephrotoxicity in rats by restoring oxidant-antioxidant balance and inhibiting inflammatory response and apoptosis in renal tissue. This is mediated, at least partly, by modulation of the Nrf2/HO-1 axis.

Natural products in traditional Chinese medicine: molecular mechanisms and therapeutic targets of renal fibrosis and state-of-the-art drug delivery systems

Renal fibrosis (RF) is the end stage of several chronic kidney diseases. Its series of changes include excessive accumulation of extracellular matrix, epithelial-mesenchymal transition (EMT) of renal tubular cells, fibroblast activation, immune cell infiltration, and renal cell apoptosis. RF can eventually lead to renal dysfunction or even renal failure. A large body of evidence suggests that natural products in traditional Chinese medicine (TCM) have great potential for treating RF. In this article, we first describe the recent advances in RF treatment by several natural products and clarify their mechanisms of action. They can ameliorate the RF disease phenotype, which includes apoptosis, endoplasmic reticulum stress, and EMT, by affecting relevant signaling pathways and molecular targets, thereby delaying or reversing fibrosis. We also present the roles of nanodrug delivery systems, which have been explored to address the drawback of low oral bioavailability of natural products. This may provide new ideas for using natural products for RF treatment. Finally, we provide new insights into the clinical prospects of herbal natural products.

Berberine: A Multi-Target Natural PCSK9 Inhibitor with the Potential to Treat Diabetes, Alzheimer's, Cancer and Cardiovascular Disease

Berberine is a natural product with a wide range of pharmacological effects. It has antimicrobial, anti-cancer, anti-inflammatory, anti-hyperlipidemic, neuroprotective, and cholesterollowering properties, among others. It has been used in traditional Chinese and Ayurvedic medicine for 3000 years and is generally well-tolerated with few side effects. Its main drawback is low oral bioavailability, which has hindered widespread clinical use. However, recent interest has surged with the emergence of evidence that berberine is effective in treating cancer, diabetes, Alzheimer's disease, and cardiovascular disease via multiple mechanisms. It enhances insulin sensitivity and secretion by pancreatic β-cells in Type 2 Diabetes Mellitus in addition to reducing pro-inflammatory cytokines such as IL-6, IL-1β, TLR4 and TNF-α. These cytokines are elevated in Alzheimer's disease, cardiovascular disease, and diabetes. Reductions in pro-inflammatory cytokine levels are associated with positive outcomes such as improved cognition, reduced cardiovascular events, and improved glucose metabolism and insulin sensitivity. Berberine is a natural PCSK9 inhibitor, which contributes to its hypolipidemic effects. It also increases low-density lipoprotein receptor expression, reduces intestinal cholesterol absorption, and promotes cholesterol excretion from the liver to the bile. This translates into a notable decrease in LDL cholesterol levels. High LDL cholesterol levels are associated with increased cardiovascular disease risk. Novel synthetic berberine derivatives are currently being developed that optimize LDL reduction, bioavailability, and other pharmacokinetic properties.

A Mechanistic Review on How Berberine Use Combats Diabetes and Related Complications: Molecular, Cellular, and Metabolic Effects

Berberine (BBR) is an isoquinoline alkaloid that can be extracted from herbs such as Coptis, Phellodendron, and Berberis. BBR has been widely used as a folk medicine to treat various disorders. It is a multi-target drug with multiple mechanisms. Studies have shown that it has antioxidant and anti-inflammatory properties and can also adjust intestinal microbial flora. This review focused on the promising antidiabetic effects of BBR in several cellular, animal, and clinical studies. Based on previous research, BBR significantly reduced levels of fasting blood glucose, hemoglobin A1C, inflammatory cytokines, and oxidative stress markers. Furthermore, BBR stimulated insulin secretion and improved insulin resistance through different pathways, including up-regulation of protein expression of proliferator-activated receptor (PPAR)-γ, glucose transporter (GLUT) 4, PI3K/AKT, and AMP-activated protein kinase (AMPK) activation. Interestingly, it was demonstrated that BBR has protective effects against diabetes complications, such as diabetic-induced hepatic damage, cardiovascular disorders, nephropathy, and neuropathy. Furthermore, multiple clinical trial studies have emphasized the ameliorative effects of BBR in type 2 diabetic patients.

p-Synephrine ameliorates alloxan-induced diabetes mellitus through inhibiting oxidative stress and inflammation via suppressing the NF-kappa B and MAPK pathways

Oxidative stress and inflammation play important roles in the development of diabetes mellitus. p-Synephrine, the primary pharmacologically active protoalkaloid in Citrus species, has been popularly consumed as a dietary supplement for weight loss management. However, the effects of p-synephrine on diabetes mellitus and the action mechanisms have not been clearly elucidated. In this study, the in vitro antioxidant effects of p-synephrine were evaluated. The data showed that p-synephrine treatment exhibited significant scavenging effects against DPPH, ABTS and OH radicals and showed high reducing power. Diabetic mice were developed by alloxan injection, followed by p-synephrine administration to investigate its hypoglycemic effects in vivo. The results showed that p-synephrine intervention significantly prevented alloxan-induced alteration in body weight, organ indexes, serum uric acid content and serum creatinine content. Meanwhile, p-synephrine application significantly improved the lipid profiles, superoxide dismutase (SOD) and catalase (CAT) activities and glutathione (GSH) contents in the serum and kidneys of diabetic mice and reduced the malondialdehyde (MDA) content in the serum of diabetic mice. Further assays suggested that p-synephrine treatment improved alloxan-induced decreases of glucose tolerance and insulin sensitivity. Also, p-synephrine supplementation altered histopathological changes in the kidneys and interscapular brown adipose tissues in diabetic mice. In addition, p-synephrine administration inhibited renal inflammation through suppressing tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) gene expression levels, as well as CD45 expression levels. The anti-inflammatory effects were probably involved in the regulation of nuclear factor-κB (NF-κB) activation and mitogen-activated protein kinase (MAPK) phosphorylation. In conclusion, p-synephrine application significantly ameliorated alloxan-induced diabetes mellitus by inhibiting oxidative stress via suppressing the NF-κB and MAPK pathways.

A Review of Fibraurea tinctoria and Its Component, Berberine, as an Antidiabetic and Antioxidant

Diabetes mellitus is a group of metabolic disorders characterized by hyperglycemia caused by resistance to insulin action, inadequate insulin secretion, or excessive glucagon production. Numerous studies have linked diabetes mellitus and oxidative stress. People with diabetes usually exhibit high oxidative stress due to persistent and chronic hyperglycemia, which impairs the activity of the antioxidant defense system and promotes the formation of free radicals. Recently, several studies have focused on exploring natural antioxidants to improve diabetes mellitus. Fibraurea tinctoria has long been known as the native Borneo used in traditional medicine to treat diabetes. Taxonomically, this plant is part of the Menispermaceae family, widely known for producing various alkaloids. Among them are protoberberine alkaloids such as berberine. Berberine is an isoquinoline alkaloid with many pharmacological activities. Berberine is receiving considerable interest because of its antidiabetic and antioxidant activities, which are based on many biochemical pathways. Therefore, this review explores the pharmacological effects of Fibraurea tinctoria and its active constituent, berberine, against oxidative stress and diabetes, emphasizing its mechanistic aspects. This review also summarizes the pharmacokinetics and toxicity of berberine and in silico studies of berberine in several diseases and its protein targets.

The mechanisms of Qizhu Tangshen formula in the treatment of diabetic kidney disease: Network pharmacology, machine learning, molecular docking and experimental assessment

BACKGROUND

Qizhu Tangshen Formula (QZTS) has been shown therapeutic effects on diabetic kidney disease (DKD). However, to date, the pharmacological mechanisms remain vague.

METHODS

To explore the underlying mechanisms of QZTS in treating DKD using network pharmacology, machine learning, molecular docking and experimental assessment.

RESULTS

First, we found that QZTS improved glycolipid metabolism disorder, decreased proteinuria and alleviated kidney tissue injury in DKD model KKAy mice. Then, by integrating multiple databases, a total of 96 targets of 74 active compounds in QZTS and 759 DKD-related genes were acquired. Next, we identified 13 hub targets of QZTS in DKD by three rank algorithms, including functional similarity, topological similarity and shortest path. Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses demonstrated that the pathways mainly centered on the processes of glycolipid metabolism disorder, inflammation and angiogenesis. Among them, VEGF signaling pathway was significantly enriched. Molecular docking showed that key active compounds of QZTS all had relatively good binding affinity with predicted hub targets. Finally, animal experiments found that QZTS significantly inhibited the secretion of plasma VEGF and downregulated the protein and mRNA expression levels of AKT, p38MAPK and VEGFR2.

CONCLUSION

Our results indicated that QZTS treated DKD via multiple targets and pathways and the VEGF signaling pathway may be highly involved in this process.

Exploring the Targets of Novel Corona Virus and Docking-based Screening of Potential Natural Inhibitors to Combat COVID-19

There is a need to explore natural compounds against COVID-19 due to their multitargeted actions against various targets of nCoV. They act on multiple sites rather than single targets against several diseases. Thus, there is a possibility that natural resources can be repurposed to combat COVID-19. However, the biochemical mechanisms of these inhibitors were not known. To reveal the mode of anti-nCoV action, structure-based docking plays a major role. The present study is an attempt to explore various potential targets of SARS-CoV-2 and the structure-based screening of various potential natural inhibitors to combat the novel coronavirus.

Berberine: An Important Emphasis on Its Anticancer Effects through Modulation of Various Cell Signaling Pathways

Cancer is the most commonly diagnosed type of disease and a major cause of death worldwide. Despite advancement in various treatment modules, there has been little improvement in survival rates and side effects associated with this disease. Medicinal plants or their bioactive compounds have been extensively studied for their anticancer potential. Novel drugs based on natural products are urgently needed to manage cancer through attenuation of different cell signaling pathways. In this regard, berberine is a bioactive alkaloid that is found in variety of plants, and an inverse association has been revealed between its consumption and cancer. Berberine exhibits an anticancer role through scavenging free radicals, induction of apoptosis, cell cycle arrest, inhibition of angiogenesis, inflammation, PI3K/AKT/mammalian target of rapamycin (mTOR), Wnt/β-catenin, and the MAPK/ERK signaling pathway. In addition, synergistic effects of berberine with anticancer drugs or natural compounds have been proven in several cancers. This review outlines the anticancer effects and mechanisms of action of berberine in different cancers through modulation of various cell signaling pathways. Moreover, the recent developments in the drug delivery systems and synergistic effect of berberine are explained.

Berberine: A Review of its Pharmacokinetics Properties and Therapeutic Potentials in Diverse Vascular Diseases

Traditional Chinese medicine plays a significant role in the treatment of various diseases and has attracted increasing attention for clinical applications. Vascular diseases affecting vasculature in the heart, cerebrovascular disease, atherosclerosis, and diabetic complications have compromised quality of life for affected individuals and increase the burden on health care services. Berberine, a naturally occurring isoquinoline alkaloid form Rhizoma coptidis, is widely used in China as a folk medicine for its antibacterial and anti-inflammatory properties. Promisingly, an increasing number of studies have identified several cellular and molecular targets for berberine, indicating its potential as an alternative therapeutic strategy for vascular diseases, as well as providing novel evidence that supports the therapeutic potential of berberine to combat vascular diseases. The purpose of this review is to comprehensively and systematically describe the evidence for berberine as a therapeutic agent in vascular diseases, including its pharmacological effects, molecular mechanisms, and pharmacokinetics. According to data published so far, berberine shows remarkable anti-inflammatory, antioxidant, antiapoptotic, and antiautophagic activity via the regulation of multiple signaling pathways, including AMP-activated protein kinase (AMPK), nuclear factor κB (NF-κB), mitogen-activated protein kinase silent information regulator 1 (SIRT-1), hypoxia-inducible factor 1α (HIF-1α), vascular endothelial growth factor phosphoinositide 3-kinase (PI3K), protein kinase B (Akt), janus kinase 2 (JAK-2), Ca²⁺ channels, and endoplasmic reticulum stress. Moreover, we discuss the existing limitations of berberine in the treatment of vascular diseases, and give corresponding measures. In addition, we propose some research perspectives and challenges, and provide a solid evidence base from which further studies can excavate novel effective drugs from Chinese medicine monomers.

Natural Products as Potential Lead Compounds for Drug Discovery Against SARS-CoV-2

For the past 2 years, the coronavirus responsible for the COVID-19 infection has become a world pandemic, ruining the lives and economies of several nations in the world. This has scaled up research on the virus and the resulting infection with the goal of developing new vaccines and therapies. Natural products are known to be a rich source of lead compounds for drug discovery, including against infectious diseases caused by microbes (viruses, bacteria and fungi). In this review article, we conducted a literature survey aimed at identifying natural products with inhibitory concentrations against the coronaviruses or their target proteins, which lie below 10 µM. This led to the identification of 42 compounds belonging to the alkaloid, flavonoid, terpenoid, phenolic, xanthone and saponin classes. The cut off concentration of 10 µM was to limit the study to the most potent chemical entities, which could be developed into therapies against the viral infection to make a contribution towards limiting the spread of the disease.

Molecular Insights of SARS-CoV-2 Infection and Molecular Treatments

The coronavirus disease emerged in December 2019 (COVID-19) caused by Severe Acute Respiratory Syndrome-related coronavirus 2 (SARS-CoV-2) and its rapid global spread has brought an international health emergency and urgent responses for seeking efficient prevention and therapeutic treatment. This has led to imperative needs for illustration of the molecular pathogenesis of SARS-CoV-2, identification of molecular targets or receptors, and development of antiviral drugs, antibodies, and vaccines. In this study, we investigated the current research progress in combating SARS-CoV-2 infection. Based on the published research findings, we first elucidated, at the molecular level, SARS-CoV-2 viral structures, potential viral host-cell-invasion and pathogenic mechanisms, main virus-induced immune responses, and emerging SARS-CoV-2 variants. We then focused on the main virus- and host-based potential targets, summarized and categorized effective inhibitory molecules based on drug development strategies for COVID-19, that can guide efforts for the identification of new drugs and treatment for this problematic disease. Current research and development of antibodies and vaccines were also introduced and discussed. We concluded that the main virus entry route- SARS-CoV-2 spike protein interaction with ACE2 receptors has played a key role in guiding the development of therapeutic treatments against COVID-19, four main therapeutic strategies may be considered in developing molecular therapeutics, and drug repurposing is likely to be an easy, fast and low-cost approach in such a short period of time with urgent need of antiviral drugs. Additionally, the quick development of antibody and vaccine candidates has yielded promising results, but the wide-scale deployment of safe and effective COVID-19 vaccines remains paramount in solving the pandemic crisis. As new variants of the virus begun to emerge, the efficacy of these vaccines and treatments must be closely evaluated. Finally, we discussed the possible challenges of developing molecular therapeutics for COVID-19 and suggested some potential future efforts. Despite the limited availability of literatures, our attempt in this work to provide a relatively comprehensive overview of current SARS-CoV-2 studies can be helpful for quickly acquiring the key information of COVID-19 and further promoting this important research to control and diminish the pandemic.

Therapeutic and delivery strategies of phytoconstituents for renal fibrosis

Chronic kidney disease (CKD) is one of the most common diseases endangering human health and life. By 2030, 14 per 100,000 people may die from CKD. Renal fibrosis (RF) is an important intermediate link and the final pathological change during CKD progression to the terminal stage. Therefore, identifying safe and effective treatment methods for RF has become an important goal. In 2018, the World Health Organization introduced traditional Chinese medicine into its effective global medical program. Various phytoconstituents that affect the RF process have been extracted from different plants. Here, we review the potential therapeutic capabilities of active phytoconstituents in RF treatment and discuss how phytoconstituents can be structurally modified or combined with other ingredients to enhance efficiency and reduce toxicity. We also summarize phytoconstituent delivery strategies to overcome renal barriers and improve bioavailability and targeting.

Phytochemicals from Plant Foods as Potential Source of Antiviral Agents: An Overview

To date, the leading causes of mortality and morbidity worldwide include viral infections, such as Ebola, influenza virus, acquired immunodeficiency syndrome (AIDS), severe acute respiratory syndrome (SARS) and recently COVID-19 disease, caused by the SARS-CoV-2 virus. Currently, we can count on a narrow range of antiviral drugs, especially older generation ones like ribavirin and interferon which are effective against viruses in vitro but can often be ineffective in patients. In addition to these, we have antiviral agents for the treatment of herpes virus, influenza virus, HIV and hepatitis virus. Recently, drugs used in the past especially against ebolavirus, such as remdesivir and favipiravir, have been considered for the treatment of COVID-19 disease. However, even if these drugs represent important tools against viral diseases, they are certainly not sufficient to defend us from the multitude of viruses present in the environment. This represents a huge problem, especially considering the unprecedented global threat due to the advancement of COVID-19, which represents a potential risk to the health and life of millions of people. The demand, therefore, for new and effective antiviral drugs is very high. This review focuses on three fundamental points: (1) presents the main threats to human health, reviewing the most widespread viral diseases in the world, thus describing the scenario caused by the disease in question each time and evaluating the specific therapeutic remedies currently available. (2) It comprehensively describes main phytochemical classes, in particular from plant foods, with proven antiviral activities, the viruses potentially treated with the described phytochemicals. (3) Consideration of the various applications of drug delivery systems in order to improve the bioavailability of these compounds or extracts. A PRISMA flow diagram was used for the inclusion of the works. Taking into consideration the recent dramatic events caused by COVID-19 pandemic, the cry of alarm that denounces critical need for new antiviral drugs is extremely strong. For these reasons, a continuous systematic exploration of plant foods and their phytochemicals is necessary for the development of new antiviral agents capable of saving lives and improving their well-being.

Downregulation of miR-588 is associated with tumor progression and unfavorable prognosis in patients with osteosarcoma

Osteosarcoma (OS) is a primary malignant tumor characterized by a high metastatic potential and poor prognosis. The dysregulation of miR-588 has been demonstrated to serve crucial roles in the progression of numerous types of cancer. The present study aimed to investigate the expression and function of miR-588 in the development of OS. To do so, clinical samples were collected and analyzed, and in vitro experiments were conducted. A total of 104 patients with OS were recruited between 2012 and 2014. The expression of miR-588 was analyzed by reverse transcription quantitative PCR. The association between miR-588 expression and the clinicopathological characteristics and survival rate of patients with OS was evaluated. Furthermore, Cell Counting Kit-8 and Transwell assays were used to evaluate the effect of miR-588 on the proliferation and the migratory and invasive abilities of various OS cell lines. The results demonstrated that miR-588 expression in OS tissues and cells was significantly lower compared with normal tissues and cells. In addition, miR-588 expression was closely associated with the Musculoskeletal Tumor Society (MSTS) staging of patients with OS. miR-588 expression and MSTS staging were therefore considered as independent indicators for the prognosis of patients with OS. In addition, miR-588 downregulation significantly stimulated the proliferation and migratory and invasive abilities of OS cells. Taken together, these findings indicated that miR-588 may serve as an independent prognostic factor and tumor suppressor in OS.

Therapeutic application of nutraceuticals in diabetic nephropathy: Current evidence and future implications

Diabetes mellitus (DM) is a common metabolic disease which may cause several complications, such as diabetic nephropathy (DN). The routine medical treatments used for DM are not effective enough and have many undesirable side effects. Moreover, the global increased prevalence of DM makes researchers try to explore potential complementary or alternative treatments. Nutraceuticals, as natural products with pharmaceutical agents, have a wide range of therapeutic properties in various pathologic conditions such as DN. However, the exact underlying mechanisms have not been fully understood. The purpose of this review is to summarize recent findings on the effect of nutraceuticals on DN.

Antiviral activity of berberine

Plants are a rich source of new antiviral, pharmacologically active agents. The naturally occurring plant alkaloid berberine (BBR) is one of the phytochemicals with a broad range of biological activity, including anticancer, anti-inflammatory and antiviral activity. BBR targets different steps in the viral life cycle and is thus a good candidate for use in novel antiviral drugs and therapies. It has been shown that BBR reduces virus replication and targets specific interactions between the virus and its host. BBR intercalates into DNA and inhibits DNA synthesis and reverse transcriptase activity. It inhibits replication of herpes simplex virus (HSV), human cytomegalovirus (HCMV), human papillomavirus (HPV), and human immunodeficiency virus (HIV). This isoquinoline alkaloid has the ability to regulate the MEK-ERK, AMPK/mTOR, and NF-κB signaling pathways, which are necessary for viral replication. Furthermore, it has been reported that BBR supports the host immune response, thus leading to viral clearance. In this short review, we focus on the most recent studies on the antiviral properties of berberine and its derivatives, which might be promising agents to be considered in future studies in the fight against the current pandemic SARS-CoV-2, the virus that causes COVID-19.

Pathogenic Pathways and Therapeutic Approaches Targeting Inflammation in Diabetic Nephropathy

Diabetic nephropathy (DN) is associated with an increased morbidity and mortality, resulting in elevated cost for public health systems. DN is the main cause of chronic kidney disease (CKD) and its incidence increases the number of patients that develop the end-stage renal disease (ESRD). There are growing epidemiological and preclinical evidence about the close relationship between inflammatory response and the occurrence and progression of DN. Several anti-inflammatory strategies targeting specific inflammatory mediators (cell adhesion molecules, chemokines and cytokines) and intracellular signaling pathways have shown beneficial effects in experimental models of DN, decreasing proteinuria and renal lesions. A number of inflammatory molecules have been shown useful to identify diabetic patients at high risk of developing renal complications. In this review, we focus on the key role of inflammation in the genesis and progression of DN, with a special interest in effector molecules and activated intracellular pathways leading to renal damage, as well as a comprehensive update of new therapeutic strategies targeting inflammation to prevent and/or retard renal injury.

Berberine for prevention of dementia associated with diabetes and its comorbidities: A systematic review

BACKGROUND

A growing number of epidemiological studies indicate that metabolic syndrome (MetS) and its associated features play a key role in the development of certain degenerative brain disorders, including Alzheimer's disease and vascular dementia. Produced by several different medicinal plants, berberine is a bioactive alkaloid with a wide range of pharmacological effects, including antidiabetic effects. However, it is not clear whether berberine could prevent the development of dementia in association with diabetes.

OBJECTIVE

To give an overview of the therapeutic potential of berberine as a treatment for dementia associated with diabetes.

SEARCH STRATEGY

Database searches A and B were conducted using PubMed and ScienceDirect. In search A, studies on berberine's antidementia activities were identified using "berberine" and "dementia" as search terms. In search B, recent studies on berberine's effects on diabetes were surveyed using "berberine" and "diabetes" as search terms.

INCLUSION CRITERIA

Clinical and preclinical studies that investigated berberine's effects associated with MetS and cognitive dysfunction were included.

DATA EXTRACTION AND ANALYSIS

Data from studies were extracted by one author, and checked by a second; quality assessments were performed independently by two authors.

RESULTS

In search A, 61 articles were identified, and 22 original research articles were selected. In search B, 458 articles were identified, of which 101 were deemed relevant and selected. Three duplicates were removed, and a total of 120 articles were reviewed for this study. The results demonstrate that berberine exerts beneficial effects directly in the brain: enhancing cholinergic neurotransmission, improving cerebral blood flow, protecting neurons from inflammation, limiting hyperphosphorylation of tau and facilitating β-amyloid peptide clearance. In addition, evidence is growing that berberine is effective against diabetes and associated disorders, such as atherosclerosis, cardiomyopathy, hypertension, hepatic steatosis, diabetic nephropathy, gut dysbiosis, retinopathy and neuropathy, suggesting indirect benefits for the prevention of dementia.

CONCLUSION

Berberine could impede the development of dementia via multiple mechanisms: preventing brain damages and enhancing cognition directly in the brain, and indirectly through alleviating risk factors such as metabolic dysfunction, and cardiovascular, kidney and liver diseases. This study provided evidence to support the value of berberine in the prevention of dementia associated with MetS.

Podoplanin mediates the renoprotective effect of berberine on diabetic kidney disease in mice

Hyperglycemia-caused podocyte injury plays a crucial role in the progress of diabetic kidney disease. Podoplanin, one of the podocyte-associated molecules, is closely related to the integrity of the glomerular filtration barrier. A number of studies demonstrate that berberine could ameliorate renal dysfunction in diabetic mice with nephropathy, but the molecular mechanisms have not been fully elucidated. In this study, we explored the relationship between the renoprotective effect of berberine and podoplanin expression in streptozotocin (STZ)-induced diabetic mice as well as mouse podocytes (MPC5 cells) cultured in high glucose (HG, 30 mM) medium. We found that the expression levels of podoplanin were significantly decreased both in the renal glomerulus of STZ-induced diabetic mice and HG-cultured MPC5 cells. We also demonstrated that NF-κB signaling pathway was activated in MPC5 cells under HG condition, which downregulated the expression level of podoplanin, thus leading to increased podocyte apoptosis. Administration of berberine (100, 200 mg/kg every day, ig, for 8 weeks) significantly improved hyperglycemia and the renal function of STZ-induced diabetic mice and restored the expression level of podoplanin in renal glomerulus. In high glucose-cultured MPC5 cells, treatment with berberine (30–120 μM) dose-dependently decreased the apoptosis rate, increased the expression of podoplanin, and inhibited the activation of NF-κB signaling pathway. When podoplanin expression was silenced with shRNA, berberine treatment still inhibited the NF-κB signaling pathway, but its antiapoptotic effect on podocytes almost disappeared. Our results suggest that berberine inhibits the activation of NF-κB signaling pathway, thus increasing the podoplanin expression to exert renoprotective effects.

C60 Fullerene as an Effective Nanoplatform of Alkaloid Berberine Delivery into Leukemic Cells

A herbal alkaloid Berberine (Ber), used for centuries in Ayurvedic, Chinese, Middle-Eastern, and native American folk medicines, is nowadays proved to function as a safe anticancer agent. Yet, its poor water solubility, stability, and bioavailability hinder clinical application. In this study, we have explored a nanosized carbon nanoparticle-C₆₀ fullerene (C₆₀)-for optimized Ber delivery into leukemic cells. Water dispersions of noncovalent C₆₀-Ber nanocomplexes in the 1:2, 1:1, and 2:1 molar ratios were prepared. UV-Vis spectroscopy, dynamic light scattering (DLS), and atomic force microscopy (AFM) evidenced a complexation of the Ber cation with the negatively charged C₆₀ molecule. The computer simulation showed that π-stacking dominates in Ber and C₆₀ binding in an aqueous solution. Complexation with C₆₀ was found to promote Ber intracellular uptake. By increasing C₆₀ concentration, the C₆₀-Ber nanocomplexes exhibited higher antiproliferative potential towards CCRF-CEM cells, in accordance with the following order: free Ber < 1:2 < 1:1 < 2:1 (the most toxic). The activation of caspase 3/7 and accumulation in the sub-G1 phase of CCRF-CEM cells treated with C₆₀-Ber nanocomplexes evidenced apoptosis induction. Thus, this study indicates that the fast and easy noncovalent complexation of alkaloid Ber with C₆₀ improved its in vitro efficiency against cancer cells.

The anti-hyperglycemia effects of Rhizoma Coptidis alkaloids: A systematic review of modern pharmacological studies of the traditional herbal medicine

Hyperglycemia is a common endocrine system disease, which seriously affects people's health with a increasing morbidity in recent years. Rhizoma Coptidis (RC), one of the most commonly used traditional Chinese medicines, has been applied to treat diabetes in clinic for thousands of years. Since scientists demonstrated that alkaloids from RC owned the amazing anti-hyperglycemia activities 30 years ago, these compounds have been widely used for the treatment of diabetes and hyperglycemia with unconspicuous toxicities and side effects. With the help of molecular biology, immunology and other techniques, the mechanisms about anti-hyperglycemia effect of RC alkaloids have been extensively discussed. Numerous studies showed that RC alkaloids balanced the glucose homeostasis not only by widely recognizing insulin resistance pathways, but also by promoting insulin secretion, regulating intestinal hormones, ameliorating gut microbiota structures and many other ways. In this review, we combine the latest advances and systematically summarize the mechanisms of RC alkaloids in treating hyperglycemia and diabetic nephropathy to provide a deeper understanding of these natural alkaloids. In addition, the important role of gut microbiota associated with the glucose metabolism is also reviewed.

Antidiabetic, Antihyperlipidemic, Antioxidant, Anti-inflammatory Activities of Ethanolic Seed Extract of Annona reticulata L. in Streptozotocin Induced Diabetic Rats

Annona reticulata L. (Bullock's heart) is a pantropic tree commonly known as custard apple, which is used therapeutically for a variety of maladies. The present research was carried out to evaluate the possible protective effects of Annona reticulata L. (A. reticulata) ethanolic seed extract on an experimentally induced type 2 diabetes rat model. Male Albino Wistar rats were randomly divided into five groups with six animals in each group viz., control rats in group I, diabetic rats in group II, diabetic rats with 50 and 100 mg/kg/bw of ethanolic seed extract of A. reticulata in groups III and IV, respectively, and diabetic rats with metformin in group V. Treatment was given for 42 consecutive days through oral route by oro-gastric gavage. Administration of A. reticulata seed extract to diabetes rats significantly restored the alterations in the levels of body weight, food and water intake, fasting blood glucose (FBG), insulin levels, insulin sensitivity, HbA1c, HOMA-IR, islet area and insulin positive cells. Furthermore, A. reticulata significantly decreased the levels of triglycerides, cholesterol, LDL, and significantly increased the HDL in diabetic rats. A. reticulata effectively ameliorated the enzymatic (ALT, AST, ALP, GGT) and modification of histopathological changes in diabetic rats. The serum levels of the BUN, creatinine levels, uric acid, urine volume, and urinary protein were significantly declined with a significant elevation in CCr in diabetic rats treated with A. reticulata. MDA and NO levels were significantly reduced with an enhancement in SOD, CAT, and GPx antioxidant enzyme activities in the kidney, liver, and pancreas of diabetic rats treated with A. reticulata. Diabetic rats treated with A. reticulata have shown up-regulation in mRNA expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2), NAD(P)H:quinone oxidoreductase 1 (NQO1), Heme oxygenase-1 (HO-1) and protein expression level of Nrf2 with diminution in Keap1 mRNA expression level in pancreas, kidney, and liver. From the outcome of the current results, it can be inferred that seed extract of A. reticulata exhibits a protective effect in diabetic rats through its anti-diabetic, anti-hyperlipidemic, antioxidant and anti-inflammatory effects and could be considered as a promising treatment therapy in the treatment of diabetes mellitus.

Polydatin inhibits the IL-1β-induced inflammatory response in human osteoarthritic chondrocytes by activating the Nrf2 signaling pathway and ameliorates murine osteoarthritis

Osteoarthritis (OA), which is characterized by progressive degradation of the articular cartilage, is the most prevalent form of human arthritis. Accumulating evidence has shown that polydatin (PD) exerts special biological functions in a variety of diseases. However, whether it protects against OA development has remained unknown. Here, we investigated the anti-inflammatory and chondroprotective effects of PD on interleukin (IL)-1β-induced human osteoarthritic chondrocytes and in the surgical destabilization of medial meniscus mouse (DMM) OA models. In vitro, PD treatment completely suppressed the over-production of pro-inflammatory mediators, including prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), nitric oxide (NO), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and IL-6 in IL-1β-induced human OA chondrocytes. Moreover, PD exerted a suppressive effect on the expression of matrix-degrading proteases, including matrix metalloproteinase 13 (MMP13) and thrombospondin motifs 5 (ADAMTS-5), which leads to the degradation of the extracellular matrix (ECM). Meanwhile, specific inhibition of the nuclear factor (erythroid-derived 2)-like 2 (Nrf2) level by short-interfering RNA (siRNA) strongly reversed the anti-inflammatory and chondroprotective effects of PD in human OA chondrocytes. The protective effects of PD were also observed in vivo. In conclusion, our studies demonstrate that PD holds novel therapeutic potential for the development of OA.

Berberine activates Nrf2 nuclear translocation and inhibits apoptosis induced by high glucose in renal tubular epithelial cells through a phosphatidylinositol 3-kinase/Akt-dependent mechanism

Apoptosis of tubular epithelial cells is a major feature of diabetic kidney disease, and hyperglycemia triggers the generation of free radicals and oxidant stress in tubular cells. Berberine (BBR) is identified as a potential anti-diabetic herbal medicine due to its beneficial effects on insulin sensitivity, glucose metabolism and glycolysis. In this study, the underlying mechanisms involved in the protective effects of BBR on high glucose-induced apoptosis were explored using cultured renal tubular epithelial cells (NRK-52E cells) and human kidney proximal tubular cell line (HK-2 cells). We identified the pivotal role of phosphatidylinositol 3-kinase (PI3K)/Akt in BBR cellular defense mechanisms and revealed the novel effect of BBR on nuclear factor (erythroid-derived 2)-related factor-2 (Nrf2) and heme oxygenase (HO)-1 in NRK-52E and HK-2 cells. BBR attenuated reactive oxygen species production, antioxidant defense (GSH and SOD) and oxidant-sensitive proteins (Nrf2 and HO-1), which also were blocked by LY294002 (an inhibitor of PI3K) in HG-treated NRK-52E and HK-2 cells. Furthermore, BBR improved mitochondrial function by increasing mitochondrial membrane potential. BBR-induced anti-apoptotic function was demonstrated by decreasing apoptotic proteins (cytochrome c, Bax, caspase3 and caspase9). All these findings suggest that BBR exerts the anti-apoptosis effects through activation of PI3K/Akt signal pathways and leads to activation of Nrf2 and induction of Nrf2 target genes, and consequently protecting the renal tubular epithelial cells from HG-induced apoptosis.

CAPE-pNO2 ameliorated diabetic nephropathy through regulating the Akt/NF-κB/ iNOS pathway in STZ-induced diabetic mice

Diabetic nephropathy (DN) is one of the most severe complications of diabetes mellitus. This study aimed to determine the effects and potential mechanism of caffeic acid para-nitro phenethyl ester (CAPE-pNO₂), a derivative of caffeic acid phenethyl ester (CAPE), on DN; In vivo, intraperitoneal injections of streptozotocin (STZ) were used to induce diabetes in mice; then, the mice were intraperitoneally injected daily with CAPE or CAPE-pNO₂ for 8 weeks. The mice were sacrificed, and blood samples and kidney tissues were collected to measure biological indexes. The results showed that CAPE and CAPE-pNO₂ could lower serum creatinine, blood urea nitrogen, 24-h albumin excretion, malondialdehyde and myeloperoxidase levels and increase superoxide dismutase activity in diabetic mice. According to HE, PAS and Masson staining, these two compounds ameliorated structural changes and fibrosis in the kidneys. In addition, the immunohistochemical and western blot results showed that CAPE and CAPE-pNO₂ inhibited inflammation through the Akt/NF-κB pathway and prevented renal fibrosis through the TGF-β/Smad pathway. In vitro, CAPE and CAPE-pNO₂ inhibited glomerular mesangial cell (GMC) proliferation, arrested cell cycle progression and suppressed ROS generation. These compounds also inhibited ECM accumulation via regulating the TGF-β1, which was a similar effect to that of the NF-κB inhibitor PDTC. More importantly, CAPE and CAPE-pNO₂ could up-regulate nitric oxide synthase expression in STZ-induced diabetic mice and HG-induced GMCs. CAPE-pNO₂ had stronger effects than CAPE both in vivo and in vitro. These data suggest that CAPE-pNO₂ ameliorated DN by suppressing oxidative stress, inflammation, and fibrosis via the Akt/NF-κB/ iNOS pathway.

NF-κβ: A Potential Target in the Management of Vascular Complications of Diabetes

Diabetes is a metabolic disorder affecting large percentage of population worldwide. NF-κβ plays key role in pathogenesis of vascular complications of diabetes. Persistent hyperglycemia activates NF-κβ that triggers expression of various cytokines, chemokines and cell adhesion molecules. Over-expression of TNF-α, interleukins, TGF-β, Bcl2 and other pro-inflammatory proteins and pro-apoptotic genes by NF-κβ is key risk factor in vascular dysfunction. NF-κβ over-expression also triggers calcification of endothelial cells leading to endothelial dysfunction and further vascular complications. Inhibition of NF-κβ pro-inflammatory pathway is upcoming novel target for management of vascular complications of diabetes. Various natural and synthetic inhibitors of NF-κβ have been studied in management of diabetic complications. Recent preclinical and clinical studies validate NF-κβ as promising target in the management of vascular complications of diabetes.

Vinpocetine mitigates proteinuria and podocytes injury in a rat model of diabetic nephropathy

Podocyte injury and glomerular basement membrane thickening have been considered as essential pathophysiological events in diabetic nephropathy. The aim of this study was to investigate the possible beneficial effects of vinpocetine on diabetes-associated renal damage. Male Wistar rats were made diabetic by injection of streptozotocin (STZ). Diabetic rats were treated with vinpocetine in a dose of 20mg/kg/day for 6 weeks. Treatment with vinpocetine resulted in a marked decrease in the levels of blood glucose, glycosylated haemoglobin, creatinine, blood urea nitrogen, urinary albumin and albumin/creatinine ratio along with an elevation in creatinine clearance rate. The renal contents of advanced glycation end-products, interleukin-10, tissue growth factor-β, nuclear factor (NF)-κB and Ras-related C3 botulinum toxin substrate 1 (Rac 1) were decreased. Renal nephrin and podocin contents were increased and their mRNA expressions were replenished in vinpocetine-treated rats. Moreover, administration of vinpocetine showed improvements in oxidative status as well as renal glomerular and tubular structures. The current investigation revealed that vinpocetine ameliorated the STZ-induced renal damage. This beneficial effect could be attributed to its antioxidant and antihyperglycemic effects parallel to its ability to inhibit NF-κB which eventually modulated cytokines production as well as nephrin and podocin proteins expression.

Berberis vulgaris and its constituent berberine as antidotes and protective agents against natural or chemical toxicities

Berberis vulgaris L (B. vulgaris) and its main constituent berberine have been used in traditional medicine for a long time. This medicinal plant and berberine have many properties that have attracted the attention of researchers over the time. According to several studies, B. vulgaris and berberine exhibited anti-inflammatory, antioxidant, anticonvulsant, antidepressant, anti-Alzheimer, anti-cancer, anti-arrhythmic, antiviral, antibacterial and anti-diabetic effects in both in vitro and invivo experiments. In regard to many reports on protective effects of B. vulgaris and berberine on natural and chemical toxins, in the current review article, the inhibitory effects of these compounds against natural, industrial, environmental and chemical toxicities with focus on cellular mechanism have been categorized. It has been mentioned that berberine could ameliorate toxicity of chemical toxins in brain, heart, kidney, liver and lung in part through antioxidant, anti-inflammatory, anti-apoptotic, modulation of mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways.

MAPK/P53-mediated FASN expression in bone tumors

The correlation between mitogen-activated protein kinase (MAPK)/P53 signaling-dependent fatty acid synthase (FASN) expression and bone tumors was examined in the present study. We established the SH081 bone tumor cell line, which was used to determine the expression of FASN and MAPK/P53 at the mRNA and protein levels in bone tumor cells and normal cells. Compared with the normal cells, the expression of MAPK/P53 and FASN mRNA was significantly elevated, whereas inhibition of MAPK/P53 decreased FASN expression. Similarly, the expression of FASN and MAPK/P53 proteins were significantly elevated in the bone tumor cells and treatment with the MAPK/P53 inhibitor decreased the expression of FASN. To determine the role of MAPK/P53 in cell proliferation, bone cancer cells were treated with MAPK/P53 inhibitor and the results showed a reduced proliferation rate. Thus, FASN promotes the development of bone tumors and MAPK/P53 signaling contributes to bone tumors by upregulating the expression of FASN.

Effect of berberine on the renal tubular epithelial-to-mesenchymal transition by inhibition of the Notch/snail pathway in diabetic nephropathy model KKAy mice

Renal tubular epithelial-to-mesenchymal transition (EMT) and renal tubular interstitial fibrosis are the main pathological changes of diabetic nephropathy (DN), which is a common cause of end-stage renal disease. Previous studies have suggested that berberine (BBR) has antifibrotic effects in the kidney and can reduce apoptosis and inhibit the EMT of podocytes in DN. However, the effect of BBR on the renal tubular EMT in DN and its mechanisms of action are unknown. This study was performed to explore the effects of BBR on the renal tubular EMT and the molecular mechanisms of BBR in DN model KKAy mice and on the high glucose (HG)-induced EMT in mouse renal tubular epithelial cells. Our results showed that, relative to the model mice, the mice in the treatment group had an improved general state and reduced blood glucose and 24-h urinary protein levels. Degradation of renal function was ameliorated by BBR. We also observed the protective effects of BBR on renal structural changes, including normalization of an index of renal interstitial fibrosis and kidney weight/body weight. Moreover, BBR suppressed the activation of the Notch/snail pathway and upregulated the α-SMA and E-cadherin levels in DN model KKAy mice. BBR was further found to prevent HG-induced EMT events and to inhibit the HG-induced expression of Notch pathway members and snail1 in mouse renal tubular epithelial cells. Our findings indicate that BBR has a therapeutic effect on DN, including its inhibition of the renal tubular EMT and renal interstitial fibrosis. Furthermore, the BBR-mediated EMT inhibition occurs through Notch/snail pathway regulation.

Diosmin Modulates the NF-kB Signal Transduction Pathways and Downregulation of Various Oxidative Stress Markers in Alloxan-Induced Diabetic Nephropathy

Hyperglycaemia-mediated oxidative stress plays an imperative role in the progression of diabetic nephropathy. NF-kB is an important transcription factor in eukaryotes which regulates a diverse array of cellular process, including inflammation, immunological response, apoptosis, growth and development. Increased expression of NF-kB plays a vital role in the pathogenesis of many inflammatory diseases including diabetic nephropathy. Hence, the present study was designed to explore the nephroprotective nature of diosmin by assessing the various biochemical parameters, markers of oxidative stress and proinflammatory cytokine levels in alloxan-induced diabetic Wistar rats. Type 2 diabetes was induced in Wistar rats by single intraperitoneal injection of alloxan (120 mg/kg body weight). Seventy-two hours after the conformation of diabetes (blood glucose level ≥ 250 mg/dl), the rats were segregated into four groups, each group having six animals. Diabetic rats were treated with diosmin at a dose of 50 mg and 100 mg/kg body weight respectively. After the 28th day of treatment, rats were sacrificed, blood serum, plasma and kidney tissue were collected for various biochemical analysis. Inflammatory cytokine levels were measured through ELISA kit. Diosmin treatment produces significant reduction in the blood glucose and plasma insulin level and increases the body weight when compared with diabetic rats. Elevated level of malondialdehyde (MDA) and decrease levels of superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH) and nitric oxide (NO) were significantly restored after 28 days of diosmin treatment. Diosmin treatment group also restores the normal architecture of the kidney tissue which was confirmed by histopathological examination. Moreover, oral administration of diosmin shows a significant normalization in the level of NF-kB, proving its pivotal role in maintaining renal function. The above ameliorative effects were more pronounced with diosmin at a dose of 100 mg/kg body weight. The above results permit us to conclude that treatment with diosmin halts hyperglycaemia-mediated oxidative stress and decline in pro-inflammatory cytokines and thus has beneficial anti-diabetic activity.

Protective Effects of Berberine on Renal Injury in Streptozotocin (STZ)-Induced Diabetic Mice

Diabetic nephropathy (DN) is a serious diabetic complication with renal hypertrophy and expansion of extracellular matrices in renal fibrosis. Epithelial-to-mesenchymal transition (EMT) of renal tubular epithelial cells may be involved in the main mechanism. Berberine (BBR) has been shown to have antifibrotic effects in liver, kidney and lung. However, the mechanism of cytoprotective effects of BBR in DN is still unclear. In this study, we investigated the curative effects of BBR on tubulointerstitial fibrosis in streptozotocin (STZ)-induced diabetic mice and the high glucose (HG)-induced EMT in NRK 52E cells. We found that BBR treatment attenuated renal fibrosis by activating the nuclear factor-erythroid 2-related factor 2 (Nrf2) signaling pathway in the diabetic kidneys. Further revealed that BBR abrogated HG-induced EMT and oxidative stress in relation not only with the activation of Nrf2 and two Nrf2-targeted antioxidative genes (NQO-1 and HO-1), but also with the suppressing the activation of TGF-β/Smad signaling pathway. Importantly, knockdown Nrf2 with siRNA not only abolished the BBR-induced expression of HO-1 and NQO-1 but also removed the inhibitory effect of BBR on HG-induced activation of TGF-β/Smad signaling as well as the anti-fibrosis effects. The data from present study suggest that BBR can ameliorate tubulointerstitial fibrosis in DN by activating Nrf2 pathway and inhibiting TGF-β/Smad/EMT signaling activity.

Synergistic chemopreventive effects of curcumin and berberine on human breast cancer cells through induction of apoptosis and autophagic cell death

Curcumin (CUR) and berberine (BBR) are renowned natural compounds that exhibit potent anticancer activities through distinct molecular mechanisms. However, the anticancer capacity of either CUR or BBR is limited. This prompted us to investigate the chemopreventive potential of co-treatment of CUR and BBR against breast cancers. The results showed that CUR and BBR in combination synergistically inhibited the growth of both MCF-7 and MDA-MB-231 breast cancer cells than the compounds used alone. Further study confirmed that synergistic anti-breast cancer activities of co-treatment of these two compounds was through inducing more apoptosis and autophagic cell death (ACD). The co-treatment-induced apoptosis was caspase-dependent and through activating ERK pathways. Our data also demonstrated that co-treatment of CUR and BBR strongly up-regulated phosphorylation of JNK and Beclin1, and decreased phosphorylated Bcl-2. Inhibition of JNK by SP600125 markedly decreased LC3-II and Beclin1, restored phosphorylated Bcl-2, and reduced the cytotoxicity induced by the two compounds in combination. These results strongly suggested that JNK/Bcl-2/Beclin1 pathway played a key role in the induction of ACD in breast cancer cells by co-treatment of CUR and BBR. This study provides an insight into the potential application of curcumin and berberine in combination for the chemoprevention and treatment of breast cancers.

Berberine improves airway inflammation and inhibits NF-κB signaling pathway in an ovalbumin-induced rat model of asthma

OBJECTIVES

Berberine has been reported for its various activities including anti-inflammatory effects and has been used in treating many diseases. However, its effects on airway inflammation in asthma have not been investigated. This study mainly aimed to detect its effects on the airway inflammation and the nuclear factor-κB (NF-κB) signaling pathway activity in a rat model of asthma.

METHODS

Asthma was induced by ovalbumin (OVA) sensitization and challenge. The asthmatic rats were respectively treated with vehicle PBS or berberine (100 mg/kg or 200 mg/kg) for 28 days. The control rats were treated with PBS. Inflammatory cells in bronchoalveolar lavage fluid (BALF) were counted and the lung inflammation was scored. Levels of NF-κB p65 (mRNA and protein), phosphorylated NF-κB p65 (p-NF-κB p65), inhibitory κB alpha (IκBα) (mRNA and protein) and phosphorylated IκBα (p-IκBα), as well as NF-κB p65 DNA-binding activity, were measured to assess the activity of NF-κB signaling pathway. Levels of the downstream inflammatory mediators of NF-κB signaling, IL-1β, IL-4, IL-5, IL-6, IL-13 and IL-17 in BALF, were measured. Besides, the serum levels of OVA-specific immunoglobulin (Ig)E were measured.

RESULTS

Results showed that OVA increased the number of inflammatory cells in BALF, elevated lung inflammation scores, enhanced the NF-κB signaling activity and promoted the production of IgE in rats. Berberine dose-dependently reversed the alterations induced by OVA in the asthmatic rats.

CONCLUSIONS

The findings suggested a therapeutic potential of berberine on OVA- induced airway inflammation. The ameliorative effects on the OVA-induced airway inflammation might be associated with the inhibition of the NF-κB signaling pathway.

Berberine as a promising anti-diabetic nephropathy drug: An analysis of its effects and mechanisms

Diabetic nephropathy is a progressive kidney disorder and is pathologically characterized by thickened glomerular and tubular basement membranes, accumulation of the extracellular matrix and increased mesangial hypertrophy. Growing evidence has suggested that diabetic nephropathy is induced by multiple factors, such as dyslipidemia, hyperglycemia, hemodynamic abnormalities and oxidative stress, based on genetic susceptibility. Berberine (BBR; [C20H18NO4](+)), an isoquinoline alkaloid, is the major active constituent of Rhizoma coptidis and Cortex phellodendri. Recent studies have demonstrated that berberine has various pharmacological activities, including lowering blood glucose, regulating blood lipids and reducing inflammation in addition to its antioxidant activity. These findings suggest that berberine has potential applications as a therapeutic drug for diabetic nephropathy, and has significant research value. However, the possible mechanisms have not been fully established. The purpose of this paper is to investigate the renoprotective mechanisms of berberine in diabetic nephropathy and highlight the importance of berberine as a potential therapeutic reagent for diabetic nephropathy treatment.

Amelioration of cisplatin-induced nephrotoxicity in rats by triterpenoid saponin of Terminalia arjuna

BACKGROUND

Cisplatin is a potent anti-tumor compound. Nephrotoxicity-inducing oxidative stress is a common side effect. This study was conducted to find out whether, the triterpenoid saponin of Terminalia arjuna (TA), Arjunolic acid which is a natural antioxidant, could prevent cisplatin-induced renal toxicity and if so, explore its possible renoprotective mechanism.

METHODS

Thirty male Sprague-Dawley rats were divided into three groups:

CONTROL GROUP

rats received saline injection, cisplatin group: rats injected intraperitoneally with 7 mg/kg cisplatin and Arjunolic acid group: rats received 20 mg/kg Arjunolic acid daily for 10 days with cisplatin injection on day 5. Serum creatinine and blood urea nitrogen (BUN) were determined and kidney sections were obtained for histopathology. Oxidative stress was evaluated in kidney homogenates by measuring malondialdehyde (MDA), reduced glutathione (GSH) and nitric oxide (NO) levels. Renal gene expressions of transforming growth factor-beta (TGF-β), nuclear factor-kappa B (NF-κB), kidney injury molecule-1 (Kim-1) and B cell lymphoma-2 (Bcl-2) were estimated.

RESULTS

Cisplatin-treated rats showed a significant reduction in renal GSH and a significant elevation of serum creatinine, BUN, MDA and NO renal levels when compared with control. Moreover, upregulation of TGF-β, NF-κB and Kim-1 along with downregulation of Bcl-2 renal expressions were also observed in cisplatin-treated rats in comparison to control. All these markers were significantly reversed by TA triterpenoid saponin administration.

CONCLUSION

Arjunolic acid ameliorated the nephrotoxic biochemical changes induced by cisplatin supporting its renoprotective effects which may be mediated by attenuation of oxidative stress markers, downregulation of renal expressions of fibrotic (TGF-β), inflammatory (NF-κB) and kidney injury (Kim-1) markers along with upregulation of renal antiapoptotic marker (Bcl-2) gene expressions.

RhoA/rho kinase signaling reduces connexin43 expression in high glucose-treated glomerular mesangial cells with zonula occludens-1 involvement

RhoA/Rho kinase (ROCK) signaling has been suggested to be involved in diabetic nephropathy (DN) pathogenesis. Altered expression of connexin43 (Cx43) has been found in kidneys of diabetic animals. Both of them have been found to regulate nuclear factor kappa-B (NF-κB) activation in high glucose-treated glomerular mesangial cells (GMCs). The aim of this study was to investigate the relationship between RhoA/ROCK signaling and Cx43 in the DN pathogenesis. We found that upregulation of Cx43 expression inhibited NF-κB p65 nuclear translocation induced by RhoA/ROCK signaling in GMCs. Inhibition of RhoA/ROCK signaling attenuated the high glucose-induced decrease in Cx43. F-actin accumulation and an enhanced interaction between zonula occludens-1 (ZO-1) and Cx43 were observed in high glucose-treated GMCs. ZO-1 depletion or disruption of F-actin formation also inhibited the reduction in Cx43 protein levels induced by high glucose. In conclusion, activated RhoA/ROCK signaling induces Cx43 degradation in GMCs cultured in high glucose, depending on F-actin regulation. Increased F-actin induced by RhoA/ROCK signaling promotes the association between ZO-1 and Cx43, which possibly triggered Cx43 endocytosis, a mechanism of NF-κB activation in high glucose-treated GMCs.

O-GlcNAcylation: The Sweet Side of the Cancer

O-GlcNAcylation is an O-linked β-N-acetylglucosamine (O-GlcNAc) moiety linked to the serine or threonine residues in proteins. O-GlcNAcylation is a dynamic post-translational modification involved in a wide range of biological processes and diseases such as cancer. This modification can increase and decrease the activity of enzymes as well as interfere with protein stability and interaction. The modulatory capacity of O-GlcNAcylation, as well as protein phosphorylation, is of paramount importance in the regulation of metabolism and intracellular signaling of tumor cells. Thus, understanding the regulation of O-GlcNAcylation in tumor cells and their difference compared to non-tumor cells may elucidate new mechanisms related to tumor generation and development, could provide a new marker to diagnosis and prognosis in patients with cancer and indicate a new target to cancer chemotherapy.

Berberine attenuates high glucose-induced proliferation and extracellular matrix accumulation in mesangial cells: involvement of suppression of cell cycle progression and NF-κB/AP-1 pathways

Berberine has been shown to have renoprotective effects on diabetes through attenuating TGF-β1 and fibronectin (FN) expression. However, how berberine regulates TGF-β1 and FN is not fully clear. Here we investigated whether berberine inhibited TGF-β1 and FN expression in high glucose-cultured mesangial cells. Berberine significantly inhibited mesangial cell proliferation and hypertrophy by increasing the cell population in G1-phase and reducing that in S-phase. In addition, berberine reversed high glucose-induced down-regulation of cyclin-dependent kinase inhibitor p21(Waf1)/(Cip1) and p27(Kip1). Berberine inhibited p65 translocation to the nucleus and c-jun phosphorylation induced by high glucose. Furthermore, berberine attenuated high glucose-induced expression of TGF-β1 and FN. Using a luciferase reporter assay, we found that high glucose-induced transcription activity of NF-κB and AP-1 was blocked by berberine. Electrophoretic mobility shift assay showed that high glucose increased that NF-κB and AP-1 DNA binding activity. These data indicate that berberine inhibited mesangial cell proliferation and hypertrophy by modulating cell cycle progress. In addition, berberine suppressed high glucose-induced TGF-β1 and FN expression by blocking NF-κB/AP-1 pathways.

Ursolic Acid provides kidney protection in diabetic rats

BACKGROUND

Diabetic nephropathy (DN) is one of the most serious microvascular complications of diabetes and the leading cause of end-stage renal failure. However, the treatment of DN is still a problem in the world. Inflammatory process plays a critical role in the development of DN. Therefore, anti-inflammatory treatment of DN is worth exploring now and in the future.

OBJECTIVE

The study aimed to evaluate the impact of ursolic acid (UA) on renal function in streptozotocin-induced diabetes.

METHODS

Rats with streptozotocin-induced diabetes were treated with UA for 16 weeks. After 16 weeks, urine albumin excretion, serum creatinine, and blood urea nitrogen were measured. In addition, renal oxidative stress level, nuclear factor kappa-B (NF-κB) activity, P-selectin expression, and kidney histopathologic changes were evaluated.

RESULTS

Sixteen weeks following streptozotocin injection, the rats produced significant alteration in renal function and increased oxidative stress, NF-κB activity, and P-selectin expression in the kidneys. Interestingly, UA significantly prevented biochemical and histopathologic changes in the kidneys associated with diabetes. Compared with untreated diabetic rats, UA treatment lowered urine albumin excretion, renal oxidative stress level, NF-κB activity, and P-selectin expression. Moreover, UA treatment also improved renal histopathologic changes in rats with diabetes.

CONCLUSIONS

UA treatment exhibited a protective effect on kidneys in diabetic rats, implying that UA could be a potential treatment for diabetic nephropathy.

Berberine ameliorates experimental diabetes-induced renal inflammation and fibronectin by inhibiting the activation of RhoA/ROCK signaling

The accumulation of glomerular extracellular matrix proteins, especially fibronectin (FN), is a critical pathological characteristic of diabetic renal fibrosis. Inflammation mediated by nuclear factor-κB (NF-κB) plays a critical role in the pathogenesis of diabetic nephropathy (DN). RhoA/ROCK signaling is responsible for FN accumulation and NF-κB activation. Berberine (BBR) treatment significantly inhibited renal inflammation and thus improved renal damage in diabetes. Here, we study whether BBR inhibits FN accumulation and NF-κB activation by inhibiting RhoA/ROCK signaling and the underlying mechanisms involved. Results showed that BBR effectively inhibited RhoA/ROCK signaling activation in diabetic rat kidneys and high glucose-induced glomerular mesangial cells (GMCs) and simultaneously down-regulated NF-κB activity, which was accompanied by reduced intercellular adhesionmolecule-1, transforming growth factor-beta 1 and FN overproduction. Furthermore, we observed that BBR abrogated high glucose-mediated reactive oxygen species generation in GMCs. BBR and N-acetylcysteine inhibited RhoA/ROCK signaling activation in high glucose-exposed GMCs. Collectively, our data suggest that the renoprotective effect of BBR on DN partly depends on RhoA/ROCK inhibition. The anti-oxidative stress effect of BBR is responsible for RhoA/ROCK inhibition in DN.