Berberine Improves TNF-α-Induced Hepatic Insulin Resistance by Targeting MEKK1/MEK Pathway

Berberine attenuates obesity-induced insulin resistance by inhibiting miR-27a secretion

INTRODUCTION

Berberine (BBR) is an alkaloid found in plants. It has neuroprotective, anti-inflammatory and lipid-lowering activity. However, the efficacy of treatment with BBR and the mechanisms through which it acts need further study.

AIMS

This study investigated the therapeutic effects and the mechanism of action of BBR on obesity-induced insulin resistance in peripheral tissues.

METHODS

High-fat-fed C57BL/6J mice and low-fat-fed C57BL/6J mice with miR-27a overexpression were given BBR intervention (100 mg/kg, po), and the oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) were performed. Palmitic acid-stimulated hypertrophic adipocyte models were treated with BBR (10 μM). Related indicators and protein expression levels were examined.

RESULTS

The AUCs of the OGTT and the ITT in the BBR intervention group were reduced significantly (p < 0.01) (p < 0.05), and the serum biochemical parameters, including FBG, TC, TG and LDL-C were significantly reduced after BBR intervention. In the in vitro experiments, the triglyceride level and volume of lipid droplets decreased significantly after BBR intervention (p < 0.01) (p < 0.05). Likewise, BBR ameliorates skeletal muscle and pancreas insulin signalling pathways in vivo and in vitro.

DISCUSSION

The results showed that BBR significantly ameliorated insulin resistance, reduced body weight and percent body fat and improved serum biochemical parameters in mice. Likewise, BBR reduced triglyceride level and lipid droplet volume in hypertrophic adipocytes, BBR improved obesity effectively. Meanwhile, BBR ameliorated the histomorphology of the pancreas, and skeletal muscle and pancreas insulin related signalling pathways of islets in in vitro and in vivo experiments. The results further demonstrated that BBR inhibited miR-27a levels in serum from obese mice and supernatant of hypertrophic adipocytes. miR-27a overexpression in low-fat fed mice indicated that miR-27a caused insulin resistance, and BBR intervention significantly improved the miR-27a induced insulin resistance status.

CONCLUSION

This study demonstrates the important role of BBR in obesity-induced peripheral insulin resistance and suggest that the mechanism of its effect may be inhibition of miR-27a secretion.

Inhibition of inflammation by berberine: Molecular mechanism and network pharmacology analysis

BACKGROUND

Traditional Chinese Medicine (TCM), renowned for its holistic approach with a 2000-year history of utilizing natural remedies, offers unique advantages in disease prevention and treatment. Berberine, found in various Chinese herbs, has been employed for many years, primarily for addressing conditions such as diarrhea and dysentery. Berberine has recently become a research focus owing to its pharmacological activities and benefits to human bodies. However, little is known about the anti-inflammatory mechanism of berberine.

PURPOSE

To summarize recent findings regarding the pharmacological effects and mechanisms of berberine anti-inflammation and highlight and predict the potential therapeutic effects and systematic mechanism of berberine.

METHODS

Recent studies (2013-2023) on the pharmacological effects and mechanisms of berberine anti-inflammation were retrieved from Web of Science, PubMed, Google Scholar, and Scopus up to July 2023 using relevant keywords. Network pharmacology and bioinformatics analysis were employed to predict the therapeutic effects and mechanisms of berberine against potential diseases.

RESULTS

The related pharmacological mechanisms of berberine anti-inflammation include the inhibition of inflammatory cytokine production (e.g., IL-1β, IL-6, TNF-α), thereby attenuating the inflammatory response; Inhibiting the activation of NF-κB signaling pathway and IκBα degradation; Inhibiting the activation of MAPK signaling pathway; Enhancing the activation of the STAT1 signaling pathway; Berberine interacts directly with cell membranes through a variety of pathways, thereby influencing cellular physiological activities. Berberine enhances human immunity and modulates immune system function, which is integral to addressing certain autoimmune and tumour-related health concerns.

CONCLUSION

This study expounds on the correlation between berberine and inflammatory diseases, encapsulating the mechanisms through which berberine treats select typical inflammatory ailments. Furthermore, it delves into a deeper understanding of berberine's effectiveness by integrating network pharmacology and molecular docking techniques in the context of treating inflammatory diseases. It provides guidance and reference for berberine's subsequent revelation of the modern scientific connotation of Chinese medicine.

Biologically active isoquinoline alkaloids covering 2019-2022

Isoquinoline alkaloids are an important class of natural products that are abundant in the plant kingdom and exhibit a wide range of structural diversity and biological activities. With the deepening of research in recent years, more and more isoquinoline alkaloids have been isolated and identified and proved to contain a variety of biological activities and pharmacological effects. In this review, we introduce the research progress of isoquinoline alkaloids from 2019 to 2022, mainly in the part of biological activities, including antitumor, antimicrobial, antidiabetic, antiviral, anti-inflammatory, antioxidant, neuroprotective, hepatoprotective, analgesic, and other activities. This study provides a clear direction for the rational development and utilization of isoquinoline alkaloids, suggesting that these alkaloids have great potential in the field of drug research.

Shen-Qi-Jiang-Tang granule ameliorates diabetic nephropathy via modulating tumor necrosis factor signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Shen-Qi-Jiang-Tang granule (SQJTG), a classic traditional Chinese medicine (TCM) prescription, has been widely used in clinical for diabetes, especially type Ⅱ diabetes. Previous anti-diabetic studies stumbled across that SQJTG has a potential kidney protective effect on diabetic nephropathy (DN). However, the protective mechanism of SQJTG on DN still needs to be explored.

AIM OF THE STUDY

The purpose of the present study was to explore the therapeutic effect of SQJTG on DN through both bioinformatics analysis and in vivo experiments.

METHODS AND MATERIALS

The TCMIP database was used for screening potential compounds and targets of SQJTG, and the GeneCards, OMIM, DrugBank, and TTD databases were used for collecting DN-related genes. Then protein-protein interaction analysis for the common targets of SQJTG and DN was performed by the STRING database. Meanwhile, KEGG and GO were carried out using the Metascape and DAVID databases. In vivo experiments, to testify the potential kidney protective effects of SQJTG, STZ-induced DN mice with different dosages of SQJTG treatment were collected and the renal tissues were detected by H&E, PAS, Masson and TUNEL staining. Immunohistochemistry and immunoblotting were used to assess the proteins' expressions. Flow cytometry and ELISA assay were used to detect the levels of pro-inflammatory cytokines.

RESULTS

Among the 338 compounds ascertained by SQJTG, there were 789 related targets as well. Moreover, 1,221 DN-related targets were predicted and 20 core targets were screened by the PPI analyses. According to GO and KEGG pathway analysis, SQJTG may affect DN via the TNF pathway. For the in vivo experiments, renal histomorphological examinations demonstrated that SQJTG treatment significantly ameliorated STZ-induced kidney damage and had a dosage dependence. Meanwhile, mice with DN were found to have dramatic increases in IL-1, TNF-α, IL-6, and IL-12, but markedly decreased after administration of SQJTG. In addition, the protein levels of TNF signaling molecules, like p-P65, p-JNK, and p-p38, showed significantly elevated in kidney tissues of DN mice and attenuated after SQJTG treatment.

CONCLUSIONS

SQJTG exerts a kidney protective effect in DN mice via modulating TNF signaling pathways, and it has promising applications for the treatment of DN.

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.

Current Insights on the Use of Insulin and the Potential Use of Insulin Mimetics in Targeting Insulin Signalling in Alzheimer's Disease

Alzheimer's disease (AD) and type 2 diabetes (T2D) are chronic diseases that share several pathological mechanisms, including insulin resistance and impaired insulin signalling. Their shared features have prompted the evaluation of the drugs used to manage diabetes for the treatment of AD. Insulin delivery itself has been utilized, with promising effects, in improving cognition and reducing AD related neuropathology. The most recent clinical trial involving intranasal insulin reported no slowing of cognitive decline; however, several factors may have impacted the trial outcomes. Long-acting and rapid-acting insulin analogues have also been evaluated within the context of AD with a lack of consistent outcomes. This narrative review provided insight into how targeting insulin signalling in the brain has potential as a therapeutic target for AD and provided a detailed update on the efficacy of insulin, its analogues and the outcomes of human clinical trials. We also discussed the current evidence that warrants the further investigation of the use of the mimetics of insulin for AD. These small molecules may provide a modifiable alternative to insulin, aiding in developing drugs that selectively target insulin signalling in the brain with the aim to attenuate cognitive dysfunction and AD pathologies.

Targeting Oxidative Stress and Inflammation in Intervertebral Disc Degeneration: Therapeutic Perspectives of Phytochemicals

Low back pain is a major cause of disability worldwide that declines the quality of life; it poses a substantial economic burden for the patient and society. Intervertebral disc (IVD) degeneration (IDD) is the main cause of low back pain, and it is also the pathological basis of several spinal degenerative diseases, such as intervertebral disc herniation and spinal stenosis. The current clinical drug treatment of IDD focuses on the symptoms and not their pathogenesis, which results in frequent recurrence and gradual aggravation. Moreover, the side effects associated with the long-term use of these drugs further limit their use. The pathological mechanism of IDD is complex, and oxidative stress and inflammation play an important role in promoting IDD. They induce the destruction of the extracellular matrix in IVD and reduce the number of living cells and functional cells, thereby destroying the function of IVD and promoting the occurrence and development of IDD. Phytochemicals from fruits, vegetables, grains, and other herbs play a protective role in the treatment of IDD as they have anti-inflammatory and antioxidant properties. This article reviews the protective effects of phytochemicals on IDD and their regulatory effects on different molecular pathways related to the pathogenesis of IDD. Moreover, the therapeutic limitations and future prospects of IDD treatment have also been reviewed. Phytochemicals are promising candidates for further development and research on IDD treatment.