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

Mechanisms and efficacy of traditional Chinese herb monomers in diabetic kidney disease

Diabetic kidney disease (DKD) is a serious complication of diabetes and is the primary cause of end-stage renal disease. Current treatment strategies primarily focus on the inhibition of the renin-angiotensin-aldosterone system and the attainment of blood glucose control. Although current medical therapies for DKD have been shown to delay disease progression and improve long-term outcomes, their efficacy is limited and they may be restricted in certain cases, particularly when hyperkalemia is present. Traditional Chinese medicine (TCM) treatment has emerged as a significant complementary approach for DKD. TCM monomers, derived from various Chinese herbs, have been found to modulate multiple therapeutic targets and exhibit a broad range of therapeutic effects in patients with DKD. This review aims to summarize the mechanisms of action of TCM monomers in the treatment of DKD, based on findings from clinical trials, as well as cell and animal studies. The results of these investigations demonstrate the potential effective use of TCM monomers in treating or preventing DKD, offering a promising new direction for future research in the field. By providing a comprehensive overview of the mechanisms and efficacy of TCM monomers in DKD, this review highlights the potential of these natural compounds as alternative therapeutic options for improving outcomes in patients with DKD.

Exploring the molecular mechanism of berberine for treating diabetic nephropathy based on network pharmacology

BACKGROUND AND PURPOSE

Diabetic nephropathy (DN) is a prevalent complication of diabetes mellitus characterized by hyperglycemia, hyperlipidemia, albuminuria and edema. Increasing evidence indicated that berberine (BBR) could alleviate the occurrence and development of DN. However, the molecular mechanism underlying the beneficial effects of BBR in the treatment of DN remains unclear.

METHODS

The online public databases were chosen to screen the relevant targets of BBR and DN and the screened overlapped targets were analyzed by GO enrichment analysis, KEGG enrichment analysis and protein-protein interaction network analysis. The interaction between BBR and the key proteinwas verified by molecular docking and cellularthermalshiftassay. Additionally, the expression of key proteins and related indicators of DN were verified by immunofluorescence and western blot in vitro and in vivo.

RESULTS

We successfully identified 92 overlapped targets of BBR and DN based on network pharmacology. Notably, VEGFR2 was identified to be the main target of BBR. Meanwhile, we found that BBR exhibited a high binding affinity to VEGFR2 protein, as confirmed by molecular docking and CETSA. This binding led to interfering with the PI3K/AKT/mTOR signaling pathway. In addition, we found that BBR could inhibit the abnormal proliferation of mesangial cells and reduce the expression of downstream pathway protein in vitro and in vivo. Finally, BBR was found to effectively lower the level of blood glucose and improve kidney function in mice, highlighting its potential as a therapeutic agent for the treatment of DN.

CONCLUSION

Berberine interfered the PI3K/AKT/mTOR signaling pathway via targeting VEGFR2 protein, further led to the inhibition of abnormal proliferation of mesangial cells and ultimately resulted in improved renal function.

The intellectual base and global trends in inflammation of diabetic kidney disease: a bibliometric analysis

Diabetic kidney disease (DKD) is a severe complication of diabetes mellitus (DM). The literature on DKD inflammation research has experienced substantial growth. However, there is a lack of bibliometric analyses. This study aimed to examine the existing research on inflammation in DKD by analyzing articles published in the Web of Science Core Collection (WOSCC) over the past 30 years. We conducted a visualization analysis using several software, including CiteSpace and VOSviewer. We found that the literature on inflammation research in DKD has experienced substantial growth, indicating a rising interest in this developing area of study. In this field, Navarro-Gonzalez, JF is the most frequently cited author, Kidney International is the most frequently cited journal, China had the highest number of publications in the field of DKD inflammation, and Monash University emerged as the institution with the most published research. The research area on inflammation in DKD primarily centers around the investigation of 'Glycation end-products', 'chronic kidney disease', and 'diabetic nephropathy'. The emerging research trends in this field will focus on the 'Gut microbiota', 'NLRP3 inflammasome', 'autophagy', 'pyroptosis', 'sglt2 inhibitor', and 'therapeutic target'. Future research on DKD may focus on further exploring the inflammatory response, identifying specific therapeutic targets, studying biomarkers, investigating stem cell therapy and tissue engineering, and exploring gene therapy and gene editing. In summary, this study examines the main areas of study, frontiers, and trends in DKD inflammation, which have significant implications for future research.

Podoplanin: A potential therapeutic target for thrombotic diseases

As a specific lymphatic marker and a key ligand of C-type lectin-like receptor 2 (CLEC-2), podoplanin (Pdpn) is involved in various physiological and pathological processes such as growth and development, respiration, blood coagulation, lymphangiogenesis, angiogenesis, and inflammation. Thrombotic diseases constitute a major cause of disability and mortality in adults, in which thrombosis and inflammation play a crucial role. Recently, increasing evidence demonstrates the distribution and function of this glycoprotein in thrombotic diseases such as atherosclerosis, ischemic stroke, venous thrombosis, ischemic-reperfusion injury (IRI) of kidney and liver, and myocardial infarction. Evidence showed that after ischemia, Pdpn can be acquired over time by a heterogeneous cell population, which may not express Pdpn in normal conditions. In this review, the research progresses in understanding the roles and mechanisms of podoplanin in thromobotic diseases are summarized. The challenges of podoplanin-targeted approaches for disease prognosis and preventions are also discussed.

Triptolide inhibits oxidative stress and inflammation via the microRNA-155-5p/brain-derived neurotrophic factor to reduce podocyte injury in mice with diabetic nephropathy

Diabetic nephropathy (DN) is a complication of diabetes. This study sought to explore the mechanism of triptolide (TP) in podocyte injury in DN. DN mice were induced by high-fat diet&streptozocin and treated with TP. Fasting blood glucose, 24 h urine microalbumin (UMA), the pathological changes of renal tissues, and ultrastructure of renal podocytes were observed. Podocytes (MPC5) were induced by high-glucose (HG) in vitro and treated with TP or microRNA (miR)-155-5p mimics, with Irbesartan as positive control. Reactive oxygen species (ROS) and levels of oxidative stress (OS) and inflammatory factors in MPC5 were detected. The levels of miR-155-5p, podocyte marker protein Nephrin, and inflammatory factors in mice and MPC5 were detected. The targeting relationship between miR-155-5p and brain-derived neurotrophic factor (BDNF) was verified. The expression levels of BDNF were detected. miR-155-5p mimics and overexpressed (oe)-BDNF plasmids were co-transfected into mouse podocytes treated with HG and TP. TP reduced fasting glucose and 24 h UMA of DN mice, alleviated the pathological damage and podocyte injury, up-regulated Nephrin level, and down-regulated miR-155-5p. TP down-regulated the high expression of miR-155-5p in HG-induced MPC5 cells and inhibited HG-induced OS and inflammatory injury, and the improvement effect of TP was better than Irbesartan. Overexpression of miR-155-5p reversed the protective effect of TP on injured mouse podocytes. miR-155-5p targeted BDNF. oe-BDNF reversed the inhibitory effect of oe-miR-155-5p on TP protection on podocyte injury in mice. Overall, TP up-regulated BDNF by inhibiting miR-155-5p, thus inhibiting OS and inflammatory damage and alleviating podocyte injury in DN mice.

The Effect of Berberine on Metabolic Profiles in Type 2 Diabetic Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective

Rhizoma Coptidis is an herb that has been frequently used in many traditional formulas for the treatment of diabetic mellitus (DM) over thousands of years. Berberine, the main active component of Rhizoma Coptidis, has been demonstrated to have the potential effect of hypoglycemia. To determine the potential advantages of berberine for diabetic care, we conducted this systematic review and meta-analysis to examine the efficacy and safety of berberine in the treatment of patients with type 2 DM.

Methods

Eight databases including PubMed, Embase, Web of Science, the Cochrane library, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Database (SinoMed), Wanfang Database, and Chinese VIP Information was searched for randomized controlled trials (RCTs) reporting clinical data regarding the use of berberine for the treatment of DM. Publication qualities were also considered to augment the credibility of the evidence. Glycemic metabolisms were the main factors studied, including glycosylated hemoglobin (HbA1c), fasting plasm glucose (FPG), and 2-hour postprandial blood glucose (2hPG). Insulin resistance was estimated by fasting blood insulin (FINS), homeostasis model assessment-insulin resistance (HOMA-IR), and body mass index (BMI). Lipid profiles were also assessed, including triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL), and high-density lipoprotein (HDL), along with inflammation factors such as C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). Serum creatinine (Scr), blood urea nitrogen (BUN), and adverse events were applied to evaluate the safety of berberine.

Results

Forty-six trials were assessed. Analysis of berberine applied alone or with standard diabetic therapies versus the control group revealed significant reductions in HbA1c (MD = −0.73; 95% CI (−0.97, −0.51)), FPG (MD = −0.86, 95% CI (−1.10, −0.62)), and 2hPG (MD = −1.26, 95% CI (−1.64, −0.89)). Improved insulin resistance was assessed by lowering FINS (MD = −2.05, 95% CI (−2.62, −1.48)), HOMA-IR (MD = −0.71, 95% CI (−1.03, −0.39)), and BMI (MD = −1.07, 95% CI (−1.76, −0.37)). Lipid metabolisms were also ameliorated via the reduction of TG (MD = −0.5, 95% CI (−0.61, −0.39)), TC (MD = 0.64, 95% CI (−0.78, −0.49)), and LDL (MD = 0.86, 95% CI (−1.06, −0.65)) and the upregulation of HDL (MD = 0.17, 95% CI (0.09, 0.25)). Additionally, berberine improved the inflammation factor.

Conclusion

There is strong evidence supporting the clinical efficacy and safety of berberine in the treatment of DM, especially as an adjunctive therapy. In the future, this may be used to guide targeted clinical use of berberine and the development of medications seeking to treat patients with T2DM and dyslipidemia.

Berberine ameliorates erectile dysfunction in rats with streptozotocin-induced diabetes mellitus through the attenuation of apoptosis by inhibiting the SPHK1/S1P/S1PR2 and MAPK pathways

BACKGROUND

The population with diabetes mellitus-induced erectile dysfunction is increasing rapidly, but current drugs are not effective in treating erectile dysfunction. Studies of the traditional Chinese medicine extract berberine on diabetes and its complications provide us with new ideas.

OBJECTIVES

To evaluate the therapeutic effect and potential mechanism of berberine on the erectile function of diabetic rats.

MATERIALS AND METHODS

Fifty male Sprague-Dawley rats were randomly grouped, and 42 rats were injected intraperitoneally with streptozotocin to establish a diabetes model. Erectile dysfunction rats were screened out through the apomorphine test and randomly divided into the diabetes mellitus and berberine groups, and these animals were administered berberine (200 mg/kg/day) and normal saline by gavage for 4 weeks. Primary corpus cavernous smooth muscle cells from healthy rats were cultured and treated with berberine.

RESULTS

Fasting blood glucose in the diabetes mellitus group was significantly increased, while berberine showed no significant effect on glucose. Erectile function was obviously impaired in the diabetes mellitus group, and berberine administration partially rescued this impairment. The expression of sphingosine kinase 1, S1PR2, and sphingosine-1-phosphate in the diabetes mellitus group was increased. Berberine partially inhibited the expression of sphingosine kinase 1 and S1PR2, but the decrease in sphingosine-1-phosphate was not significant. Moreover, mitogen-activated protein kinase pathway factor expression was upregulated and eNOS activity was decreased in the diabetes mellitus group. Berberine treatment could partially reverse these alterations. Severe fibrosis and apoptosis were detected in diabetic rats, accompanied by higher expression of TGFβ1, collagen I/IV, Bax/Bcl-2, and caspase 3 than in the other groups. However, supplementation with berberine inhibited the expression of these proteins and attenuated fibrosis and apoptosis.

CONCLUSIONS

Berberine ameliorated erectile dysfunction in rats with diabetes mellitus, possibly by improving endothelial function and inhibiting apoptosis and fibrosis by suppressing the sphingosine kinase 1/sphingosine-1-phosphate/S1PR2 and mitogen-activated protein kinase pathways.

Clinical efficacies, underlying mechanisms and molecular targets of Chinese medicines for diabetic nephropathy treatment and management

Diabetic nephropathy (DN) has been recognized as a severe complication of diabetes mellitus and a dominant pathogeny of end-stage kidney disease, which causes serious health problems and great financial burden to human society worldwide. Conventional strategies, such as renin-angiotensin-aldosterone system blockade, blood glucose level control, and bodyweight reduction, may not achieve satisfactory outcomes in many clinical practices for DN management. Notably, due to the multi-target function, Chinese medicine possesses promising clinical benefits as primary or alternative therapies for DN treatment. Increasing studies have emphasized identifying bioactive compounds and molecular mechanisms of reno-protective effects of Chinese medicines. Signaling pathways involved in glucose/lipid metabolism regulation, antioxidation, anti-inflammation, anti-fibrosis, and podocyte protection have been identified as crucial mechanisms of action. Herein, we summarize the clinical efficacies of Chinese medicines and their bioactive components in treating and managing DN after reviewing the results demonstrated in clinical trials, systematic reviews, and meta-analyses, with a thorough discussion on the relative underlying mechanisms and molecular targets reported in animal and cellular experiments. We aim to provide comprehensive insights into the protective effects of Chinese medicines against DN.

Sarsasapogenin restores podocyte autophagy in diabetic nephropathy by targeting GSK3β signaling pathway

Podocyte injury following abnormal podocyte autophagy plays an indispensable role in diabetic nephropathy (DN), therefore, restoration of podocyte autophagy is considered as a feasible strategy for the treatment of DN. Here, we investigated the preventive effects of sarsasapogenin (Sar), the main active ingredient in Anemarrhena asphodeloides Bunge, on the podocyte injury in diabetic rats, and tried to illustrate the mechanisms underlying the effects in high glucose (HG, 40 mM)-treated podocytes (MPs). Diabetes model was established in rats with single streptozocin (60 mg· kg^-1) intraperitoneal administration. The rats were then treated with Sar (20, 60 mg· kg^-1· d^-1, i.g.) or a positive control drug insulin (INS) (40 U· kg^-1· d^-1, i.h.) for 10 weeks. Our results showed that both Sar and insulin precluded the decreases of autophagy-related proteins (ATG5, Beclin1 and LC3B) and podocyte marker proteins (podocin, nephrin and synaptopodin) in the diabetic kidney. Furthermore, network pharmacology was utilized to assess GSK3β as the potential target involved in the action of Sar on DN and were substantiated by significant changes of GSK3β signaling in the diabetic kidney. The underlying protection mechanisms of Sar were explored in HG-treated MPs. Sar (20, 40 μM) or insulin (50 mU/L) significantly increased the expression of autophagy- related proteins and podocyte marker proteins in HG-treated MPs. Furthermore, Sar or insulin treatment efficiently regulatedphosphorylation at activation and inhibition sites of GSK3β. To sum up, this study certifies that Sar meliorates experimental DN through targeting GSK3β signaling pathway and restoring podocyte autophagy.

Effects of alkaloids on peripheral neuropathic pain: a review

Neuropathic pain is a debilitating pathological pain condition with a great therapeutic challenge in clinical practice. Currently used analgesics produce deleterious side effects. Therefore, it is necessary to investigate alternative medicines for neuropathic pain. Chinese herbal medicines have been widely used in treating intractable pain. Compelling evidence revealed that the bioactive alkaloids of Chinese herbal medicines stand out in developing novel drugs for neuropathic pain due to multiple targets and satisfactory efficacy. In this review, we summarize the recent progress in the research of analgesic effects of 20 alkaloids components for peripheral neuropathic pain and highlight the potential underlying molecular mechanisms. We also point out the opportunities and challenges of the current studies and shed light on further in-depth pharmacological and toxicological studies of these bioactive alkaloids. In conclusion, the alkaloids hold broad prospects and have the potentials to be novel drugs for treating neuropathic pain. This review provides a theoretical basis for further applying some alkaloids in clinical trials and developing new drugs of neuropathic pain.

Investigation of hub genes involved in diabetic nephropathy using biological informatics methods

Background

The aim of this study was to find genes with significantly aberrant expression in diabetic nephropathy (DN) and determine their underlying mechanisms.

Methods

GSE30528 and GSE1009 were obtained by querying the Gene Expression Omnibus (GEO) database. The difference in target gene expression between normal renal tissues and kidney tissues in patients with DN was screened by using the GEO2R tool. Using the Database for Annotation, Visualization, and Integrated Discovery (DAVID) database, differentially expressed genes (DEGs) were analysed by Gene Ontology (GO) annotation and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. Then, the protein-protein interactions (PPIs) of DEGs were analyzed by Cytoscape with the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database, and the hub genes in this PPI network were recognized by centrality analysis.

Results

There were 110 genes with significant expression differences between normal and DN tissues. The differences in gene expression involved many functions and expression pathways, such as the formation of the extracellular matrix and the construction of the extracellular domain. The correlation analysis and subgroup analysis of 14 hub genes and the clinical characteristics of DN showed that CTGF, ALB, PDPN, FLT1, IGF1, WT1, GJA1, IGFBP2, FGF9, BMP2, FGF1, BMP7, VEGFA, and TGFBR3 may be involved in the progression of DN.

Conclusions

We confirmed the differentially expressed hub genes and other genes which may be the novel biomarker and target candidates in DN.

Silencing PEG3 inhibits renal fibrosis in a rat model of diabetic nephropathy by suppressing the NF-κB pathway

As paternally expressed gene 3 (PEG3), which can activate NF-κB pathway, plays an important role in the development of renal fibrosis in diabetic nephropathy (DN), the present study aimed to investigate the interaction of PEG3 and the NF-κB pathway on renal fibrosis in a DN model. Following the induction of the rat model of DN, a series of experiments were used to measure serum creatinine (Scr), blood urea nitrogen (BUN), urine protein for 24 h (UP24 h), proliferation of renal fibroblasts, positive expression of PEG3, Collagen I and Collagen II protein, the activity of NF-κB, collagen fiber expression and the FSP1⁺ cell ratio (fibroblast marker, reflecting renal fibrosis). Silencing of PEG3 or inhibition of the NF-κB pathway decreased the levels of Scr, BUN, and UP24 h, down-regulated Collagen I protein and up-regulated Collagen II protein. These treatments also down-regulated the expression of PEG3, NF-κB, Vimentin, α-SMA, FN, caspase-3 and FSP1 and the extents of IκBα, inhibitor of kappa B (IκB) kinase β (IKKβ), and NF-κB p65 phosphorylation while that of E-cadherin was up-regulated, and the ratio of FSP1⁺ cells was decreased. Taken together, these results showed that silencing of PEG3 inhibited the NF-κB pathway, thereby alleviating renal fibrosis in DN, thus presenting PEG3 as a potential therapeutic target in renal fibrosis in DN.