Salvia miltiorrhiza protects against diabetic nephropathy through metabolome regulation and wnt/β-catenin and TGF-β signaling inhibition

Oridonin ameliorates renal fibrosis in diabetic nephropathy by inhibiting the Wnt/β-catenin signaling pathway

Diabetic nephropathy (DN) is one of the most serious and frequent complications among diabetes patients and presently constitutes vast the cases of end-stage renal disease worldwide. Tubulointerstitial fibrosis is a crucial factor related to the occurrence and progression of DN. Oridonin (Ori) is a diterpenoid derived from rubescens that has diverse pharmacological properties. Our previous study showed that Ori can protect against DN by decreasing the inflammatory response. However, whether Ori can alleviate renal fibrosis in DN remains unknown. Here, we investigated the mechanism through which Ori affects the Wnt/β-catenin signaling pathway in diabetic rats and human proximal tubular epithelial cells (HK-2) exposed to high glucose (HG) levels. Our results revealed that Ori treatment markedly decreased urinary protein excretion levels, improved renal function and alleviated renal fibrosis in diabetic rats. In vitro, HG treatment increased the migration of HK-2 cells while reducing their viability and proliferation rate, and treatment with Ori reversed these changes. Additionally, the knockdown of β-catenin arrested cell migration and reduced the expression levels of Wnt/β-catenin signaling-related molecules (Wnt4, p-GSK3β and β-catenin) and fibrosis-related molecules (α-smooth muscle actin, collagen I and fibronectin), and Ori treatment exerted an effect similar to that observed after the knockdown of β-catenin. Furthermore, the combination of Ori treatment and β-catenin downregulation exerted more pronounced biological effects than treatment alone. These findings may provide the first line of evidence showing that Ori alleviates fibrosis in DN by inhibiting the Wnt/β-catenin signaling pathway and thereby reveal a novel therapeutic avenue for treating tubulointerstitial fibrosis.

Chinese herbal medicine for the treatment of diabetic nephropathy: From clinical evidence to potential mechanisms

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetic nephropathy (DN) is a typical chronic microvascular complication of diabetes, characterized by proteinuria and a gradual decline in renal function. At present, there are limited clinical interventions aimed at preventing the progression of DN to end-stage renal disease (ESRD). However, Chinese herbal medicine presents a distinct therapeutic approach that can be effectively combined with conventional Western medicine treatments to safeguard renal function. This combination holds considerable practical implications for the treatment of DN.

AIM OF THE STUDY

This review covers commonly used Chinese herbal remedies and decoctions applicable to various types of DN, and we summarize the role played by their active ingredients in the treatment of DN and their mechanisms, which includes how they might improve inflammation and metabolic abnormalities to provide new ideas to cope with the development of DN.

MATERIALS AND METHODS

With the keywords "diabetic nephropathy," "Chinese herbal medicine," "clinical effectiveness," and "bioactive components," we conducted an extensive literature search of several databases, including PubMed, Web of Science, CNKI, and Wanfang database, to discover studies on herbal formulas that were effective in slowing the progression of DN. The names of the plants covered in the review have been checked at MPNS (http://mpns.kew.org).

RESULTS

This review demonstrates the superior total clinical effective rate of combining Chinese herbal medicines with Western medicines over the use of Western medicines alone, as evidenced by summarizing the results of several clinical trials. Furthermore, the review highlights the nephroprotective effects of seven frequently used herbs exerting beneficial effects such as podocyte repair, anti-fibrosis of renal tissues, and regulation of glucose and lipid metabolism through multiple signaling pathways in the treatment of DN.

CONCLUSIONS

The potential of herbs in treating DN is evident from their excellent effectiveness and the ability of different herbs to target various symptoms of the condition. However, limitations arise from the deficiencies in interfacing with objective bioindicators, which hinder the integration of herbal therapies into modern medical practice. Further research is warranted to address these limitations and enhance the compatibility of herbal therapies with contemporary medical standards.

Biomedicine and pharmacotherapeutic effectiveness of combinatorial atorvastatin and quercetin on diabetic nephropathy: An in vitro study

INTRODUCTION

Diabetic nephropathy is a type of kidney disorder that develops as a complication of multifactorial diabetes. Diabetic nephropathy is characterized by microangiopathy, resulting from glucose metabolism, oxidative stress, and changes in renal hemodynamics. This study strived to evaluate the in vitro cytoprotective activity of atorvastatin (ATR), and quercetin (QCT) alone and in combination against diabetic nephropathy.

METHODS

The MTT assay was utilized to analyze the effects of the test compounds on NRK-52E rat kidney epithelial cells. The detection of apoptosis and ability to scavenge free radicals was assessed via acridine orange-ethidium bromide (AO-EB) dual fluorescence staining, and 2,2-diphenyl-1-picrylhydrazyfree assay (DPPH), respectively. The ability of anti-inflammatory effect of the test compounds and western blot analysis against TGF-β, TNF-α, and IL-6 further assessed to determine the combinatorial efficacy.

RESULTS

Atorvastatin and quercetin treatment significantly lowered the expression of TGF-β, TNF-α, and IL-6 indicating the protective role in Streptozotocin-induced nephrotoxicity. The kidney cells treated with a combination of atorvastatin and quercetin showed green fluorescing nuclei in the AO-EB staining assay, indicating that the combination treatment restored cell viability. Quercetin, both alone and in combination with atorvastatin, demonstrated strong DPPH free radical scavenging activity and further encountered an anti-oxidant and anti-inflammatory effect on the combination of these drugs.

CONCLUSION

Nevertheless, there is currently no existing literature that reports on the role of QCT as a combination renoprotective drug with statins in the context of diabetic nephropathy. Hence, these findings suggest that atorvastatin and quercetin may have clinical potential in treating diabetic nephropathy.

Salvianolic acid B and tanshinone IIA synergistically improve early diabetic nephropathy through regulating PI3K/Akt/NF-κB signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetic nephropathy (DN) is one of the most common and serious complications of diabetes, which lacks effective treatment. Salviae Miltiorrhizae Radix Et Rhizoma is one of the key compatible traditional Chinese medicine in the prescription for the treatment of DN. Salvianolic acid B and tanshinone IIA are two monomer active components with high content and clear structure in Salvia miltiorrhiza, which can effectively improve early (DN), respectively.

AIM OF THE STUDY

To evaluate the compatible effect of salvianolic acid B and tanshinone IIA on early DN rats and elucidate the mechanism.

METHODS

Early DN rats were induced by streptozotocin combined with high glucose and high fat diet, and intervened by salvianolic acid B, tanshinone IIA and their combinations. The pathological sections of kidney, liver and biochemical indexes were analyzed. Network pharmacology method was used to predict the possible mechanism. The mechanisms were elucidated by metabolomics, Elisa, and Western blot.

RESULTS

Given our analysis, salvianolic acid B and tanshinone IIA can synergistically regulate 24 h UTP, Urea and Scr and improve kidney damage in early DN rats. The metabolic abnormalities of early DN rats were improved by regulating the biosynthesis of saturated fatty acids, glycerol phospholipid metabolism, steroid biosynthesis, alanine, and arachidonic acid. Salvianolic acid B combined with tanshinone IIA at a mass ratio of 13.4:1 can significantly reduce kidney inflammation, up-regulate p-PI3K/PI3K and p-Akt/Akt and down-regulate p-NF-κB/NF-κB, which better than the single-used group and can be reversed by PI3K inhibitor LY294002.

CONCLUSION

Salvianolic acid B and tanshinone IIA can synergistically improve glucose and lipid disorders, liver and kidney damage, and resist kidney inflammation in early DN rats, and the mechanism may be related to regulating PI3K/Akt/NF-κB signaling pathway.

Effect and pharmacological mechanism of Salvia miltiorrhiza and its characteristic extracts on diabetic nephropathy

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetic nephropathy (DN) is a severe diabetic microvascular complication with an increasing prevalence rate and lack of effective treatment. Traditional Chinese medicine has been proven to have favorable efficacy on DN, especially Salvia miltiorrhiza Bunge (SM), one of the most critical and conventional herbs in the treatment. Over the past decades, studies have demonstrated that SM is a potential treatment for DN, and the exploration of the underlying mechanism has also received much attention.

AIM OF THIS REVIEW

This review aims to systematically study the efficacy and pharmacological mechanism of SM in the treatment of DN to understand its therapeutic potential more comprehensively.

MATERIALS AND METHODS

Relevant information was sourced from Google Scholar, PubMed, Web of Science, and CNKI databases.

RESULTS

Several clinical trials and systematic reviews have indicated that SM has definite benefits on the kidneys of diabetic patients. And many laboratory studies have further revealed that SM and its characteristic extracts, mainly including salvianolic acids and tanshinones, can exhibit pharmacological activity against DN by the regulation of metabolism, renal hemodynamic, oxidative stress, inflammation, fibrosis, autophagy, et cetera, and several involved signaling pathways, thereby preventing various renal cells from abnormal changes in DN, including endothelial cells, podocytes, epithelial cells, and mesangial cells.

CONCLUSION

As a potential drug for the treatment of DN, SM has multi-component, multi-target, and multi-pathway pharmacological effects. This work will not only verify the satisfactory curative effect of SM in the treatment of DN but also provide helpful insights for the development of new anti-DN drugs and the application of traditional Chinese medicine.

Application of Metabolomics and Traditional Chinese Medicine for Type 2 Diabetes Mellitus Treatment

Diabetes is a major global public health problem with high incidence and case fatality rates. Traditional Chinese medicine (TCM) is used to help manage Type 2 Diabetes Mellitus (T2DM) and has steadily gained international acceptance. Despite being generally accepted in daily practice, the TCM methods and hypotheses for understanding diseases lack applicability in the current scientific characterization systems. To date, there is no systematic evaluation system for TCM in preventing and treating T2DM. Metabonomics is a powerful tool to predict the level of metabolites in vivo, reveal the potential mechanism, and diagnose the physiological state of patients in time to guide the follow-up intervention of T2DM. Notably, metabolomics is also effective in promoting TCM modernization and advancement in personalized medicine. This review provides updated knowledge on applying metabolomics to TCM syndrome differentiation, diagnosis, biomarker discovery, and treatment of T2DM by TCM. Its application in diabetic complications is discussed. The combination of multi-omics and microbiome to fully elucidate the use of TCM to treat T2DM is further envisioned.

Astragalus membranaceus and Salvia miltiorrhiza ameliorate diabetic kidney disease via the "gut-kidney axis"

BACKGROUND

The combination of Astragalus membranaceus and Salvia miltiorrhiza (AS) is an effective prescription for treating diabetic kidney disease (DKD) in traditional Chinese medicine. Its efficacy in treating DKD has been confirmed, but the potential regulatory mechanism has not yet been fully clarified.

PURPOSE

To explore the mechanism by which AS regulates the "gut-metabolism-transcription" coexpression network under the action of the "gut-kidney axis" to ameliorate DKD.

METHODS

SD rats were used to establish the DKD model by injecting STZ. After AS intervention, the structure and function of the kidney and colon were observed. We sequenced the gut microbiota utilizing 16S rDNA, identified serum differential metabolites using LC‒MS/MS, and observed renal mRNA expression by RNA seq. The "gut-metabolism-transcription" coexpression network was further constructed, and the target bacteria, target metabolites, and target genes of AS were ultimately screened and validated.

RESULTS

AS improved renal pathology and functional damage and increased the abundance of Akkermansia, Akkermansia_muciniphila, Lactobacillus and Lactobacillus_murinus. Fourteen target metabolites of AS were identified, which were mainly concentrated in 19 KEGG pathways, including sphingolipid metabolism and glycerophospholipid metabolism. Sixty-three target mRNAs of AS were identified. The top 20 pathways were closely related to glycolipid metabolism, and 14 differential mRNAs were expressed in these pathways. Correlation analysis showed that Akkermansia, Akkermansia muciniphila, Lactobacillus and Lactobacillus murinus were closely associated with sphingolipid metabolism, glycerophospholipid metabolism, arachidonic acid metabolism, ascorbate and aldarate metabolism and galactose metabolism. Moreover, the target metabolites and target mRNAs of AS were also enriched in five identical pathways of sphingolipid metabolism, glycerophospholipid metabolism, arachidonic acid metabolism, ascorbate and aldarate metabolism and galactose metabolism, including 8 different metabolites, such as sphingosine, and 5 different genes, such as Kng1. The 8 metabolites had high AUC prediction values, and the validation of the 5 genes was consistent with the sequencing results.

CONCLUSION

Our research showed that AS can improve DKD via the "gut-kidney axis". Akkermansia muciniphila and Lactobacillus murinus were the main driving bacteria, and five pathways related to glycolipid metabolism, especially sphingolipid metabolism and glycerophospholipid metabolism, may be important follow-up reactions and regulatory mechanisms.

DPP-4 Inhibitors Suppress Tau Phosphorylation and Promote Neuron Autophagy through the AMPK/mTOR Pathway to Ameliorate Cognitive Dysfunction in Diabetic Mellitus

Dipeptidyl peptidase-4 (DPP-4) inhibitors have been considered as incretin-based agents that signal through GLP-1R. Our high-throughput RNA sequencing (RNA-seq) and bioinformatics methods indicated that GLP-1R, downregulated in diabetes mellitus (DM), was a potential target of DPP-4 inhibitors, which was further confirmed in DM rats. Thus, this study illuminated the alleviatory mechanism of DPP-4 on cognitive dysfunction in diabetes mellitus (DM), which may be associated with GLP-1R signaling. DM rats were administered with DPP-4 inhibitors, Chloroquine (an autophagy inhibitor), Exendin 9-39 (a GLP-1R antagonist), or Compound C (a specific inhibitor of AMPK). An in vitro model of DM was induced in rat hippocampal neuronal cell line H19-7 by exposure to high glucose (HG) and high fat (HF), followed by treatment with the above inhibitors and antagonists. It was found that cognitive dysfunction was promoted, and LC3 expression was lowered in DM rats by an autophagy inhibitor. The DPP-4 inhibitors decreased cognitive dysfunction, repressed Tau phosphorylation, and enhanced GLP-1R protein level, LC3 expression, and AMPK and mTOR phosphorylation in DM rats, while GLP-1R antagonist, an autophagy inhibitor, or AMPK inhibitor counteracted these effects. Such effects were also observed in HG/HF-induced neurons. In conclusion, our data elucidated the alleviatory mechanism of DPP-4 inhibitors in the cognitive dysfunction of DM rats via the AMPK/mTOR pathway.

The protective mechanism of Dehydromiltirone in diabetic kidney disease is revealed through network pharmacology and experimental validation

Background: Salvia miltiorrhiza (SM) is an effective traditional Chinese medicine for treating DKD, but the exact mechanism is elusive. In this study, we aimed to investigate and confirm the method underlying the action of the active components of SM in the treatment of DKD. Methods: Renal tissue transcriptomics and network pharmacology of DKD patients was performed to identify the active components of SM and the disease targets of DKD. Next, the point of convergence among these three groups was studied. Potential candidate genes were identified and analyzed using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG). The component-target networks were modelled and visualized with Cytoscape. In addition, docking studies were performed to validate our potential target predictions. Lastly, in vitro and in vivo experiments were performed to understand the role of Dehydromiltirone (DHT), the active component of SM, in the phenotypic switching of mesangial cells. Results: Transcriptomics of DKD patients' renal tissues screened 4,864 differentially expressed genes. Eighty-nine active components of SM and 161 common targets were found. Functional enrichment analysis indicated that 161 genes were enriched in apoptosis, the PI3K-AKT signaling pathway, and the AGE-RAGE signaling pathway in diabetes complications. Molecular docking and molecular dynamic simulations show that DHT can bind to functional PIK3CA pockets, thereby becoming a possible inhibitor of PIK3CA. In vitro study demonstrated that DHT reduced the expression of phenotypic switching markers α-SMA, Col-I, and FN in HMCs by downregulating the over-activation of the PI3K-AKT signaling pathway through the inhibition of PIK3CA. Furthermore, the DKD mouse model confirmed that DHT could reduce proteinuria and improve glomerular hypertrophy in vivo. Conclusion: DHT was identified as the key active component of SM, and its therapeutic effect on DKD was achieved by inhibiting the phenotypic switching of mesangial cells via the PIK3CA signaling pathway.

Niclosamide from an anthelmintic drug to a promising adjuvant therapy for diabetic kidney disease: randomized clinical trial

BACKGROUND

Diabetic kidney disease (DKD) is a serious complication that begins with albuminuria and often leads to a rapid progressive decline in renal function. Niclosamide is a potent inhibitor of the Wnt/β-catenin pathway, which controls the expression of multiple genes of the renin-angiotensin-aldosterone system (RAAS), which in turn is influences the progression of DKD. This study was conducted to evaluate the effect of niclosamide as adjuvant therapy on DKD.

METHODS

Out of 127 patients screened for eligibility, 60 patients completed the study. After randomization, 30 patients in the niclosamide arm received ramipril plus niclosamide, and 30 patients in the control arm received ramipril only for 6 months. The primary outcomes were the changes in urinary albumin to creatinine ratio (UACR), serum creatinine, and estimated glomerular filtration rate (eGFR). The secondary outcomes were measurements of urinary matrix metalloproteinase-7 (MMP-7), 8-hydroxy-2'-deoxyguanosine (8-OHdG), and podocalyxin (PCX). Comparisons between the two arms were done using student t-test. Correlation analysis was done using Pearson correlation.

RESULTS

Niclosamide decreased UACR by 24% (95% CI - 30 to - 18.3%) while there was a rise in UACR in the control arm by 11% (95% CI 4 to 18.2%) after 6 months (P < 0.001). Moreover, a significant reduction in MMP-7 and PCX was noticed in the niclosamide arm. Regression analysis revealed a strong association between MMP-7, which is a noninvasive biomarker predicting the activity of the Wnt/β-catenin signaling, and UACR. A 1 mg/dL decline in MMP-7 level was associated with a 25 mg/g lowering in UACR (B = 24.95, P < 0.001).

CONCLUSION

The addition of niclosamide to patients with diabetic kidney disease receiving an angiotensin-converting enzyme inhibitor significantly reduces albumin excretion. Further larger-scale trials are needed to confirm our results.

TRIAL REGISTRATION

The study was prospectively registered on clinicaltrial.gov on March 23, 2020, with identification code NCT04317430.

Chuanzhitongluo capsule ameliorates microcirculatory dysfunction in rats: Efficacy evaluation and metabolic profiles

Background: Ischemic stroke is a leading cause of mortality and disability worldwide. Microcirculatory dysfunction is the foremost hindrance for a good clinical prognosis in ischemic stroke patients. Clinical researches show that Chuanzhitongluo capsule (CZTL) has a curative effect during the recovery period of ischemic stroke, which contributes to a good prognosis. However, it is not known whether CZTL treats ischemic stroke by ameliorating microcirculation dysfunction.

Objective: In this study, we investigated the influence of CZTL on microcirculation and its underlying mechanism.

Methods: A rat model of acute microcirculatory dysfunction was established by stimuli of adrenaline and ice water. The microcirculatory damage in model rats and the efficacy of CZTL were assessed by detecting laser speckle contrast imaging, coagulation function, hemorheology, vasomotor factor and microcirculation function. The potential mechanism of CZTL action was explored by the untargeted metabolomic analysis based on ultra-performance liquid chromatography-quadrupole-time of flight-mass spectrometry.

Results: Laser speckle contrast imaging showed that model rats suffered low perfusion in ears, feet and tails, and CZTL treatment increased microcirculatory blood flow. Coagulation function detection results showed that CZTL diminished the reduction of thrombin time, prothrombin time, activated partial thromboplastin time and the elevated fibrinogen level caused by acute microcirculatory dysfunction. Furthermore, CZTL could recover the increased blood viscosity as well as the abnormal vasomotor and microcirculation function in rats with acute microcirculatory dysfunction. Metabolomics analysis indicated that CZTL might regulate sphingolipid metabolism and arachidonic acid metabolism to exert protective effects on microcirculation.

Conclusion: These results elucidated that CZTL was highly effective against microcirculatory dysfunction and its potential mechanisms related with the modulation of sphingolipid and arachidonic acid metabolic pathways. The present study provided a new perspective on the clinical application of CZTL, and it contribute to explore novel therapeutic drug against microcirculatory dysfunction.

Multi-omics analysis reveals the pathogenesis of db/db mice diabetic kidney disease and the treatment mechanisms of multi-bioactive compounds combination from Salvia miltiorrhiza

Diabetic kidney disease (DKD) is a common diabetic complication. Salvia miltiorrhiza has significant therapeutic effects on diabetes complications, although the mechanism remains unclear. Here, biochemical indicators and pathological changes were used to screen out the optimal Salvia miltiorrhiza multi-bioactive compounds combination. Metabolomics, transcriptomics and proteomics were used to explore the pathogenesis of DKD. RT-PCR and parallel reaction monitoring targeted quantitative proteome analysis were utilized to investigate treatment mechanisms of the optimal Salvia miltiorrhiza multi-bioactive compounds combination. The db/db mice showed biochemical abnormalities and renal lesions. The possible metabolic pathways were steroid hormone biosynthesis and sphingolipid metabolism. The 727 differential genes found in transcriptomics were associated with biochemical indicators via gene network to finally screen 11 differential genes, which were mainly key genes of TGF-β/Smad and PI3K/Akt/FoxO signaling pathways. Salvia miltiorrhiza multi-bioactive compounds combination could significantly regulate the Egr1, Pik3r3 and Col1a1 genes. 11 differentially expressed proteins involved in the two pathways were selected, of which 9 were significantly altered in db/db mice compared to db/m mice. Salvia miltiorrhiza multi-bioactive compounds combination could callback Q9DBM2, S4R1W1, Q91Y97, P47738, A8DUK4, and A2ARV4. In summary, Salvia miltiorrhiza multi-bioactive compounds combination may ameliorate kidney injury in diabetes through regulation of TGF-β/Smad and PI3K/Akt/FoxO signaling pathways.

Altered Expression of EMT-Related Factors Snail, Wnt4, and Notch2 in the Short-Term Streptozotocin-Induced Diabetic Rat Kidneys

Background: The aim of this study was to determine the expression of epithelial to mesenchymal transition (EMT)-related transcription factors Snail, Wnt4, and Notch2 with key roles in renal fibrosis, in different renal areas of diabetic rats: glomeruli (G), proximal and distal convoluted tubules (PCT; DCT). Methods: Male Sprague Dawley rats were instilled with 55 mg/kg streptozotocin (diabetes mellitus type I model, DM group) or citrate buffer (control group). Kidney samples were collected 2 weeks and 2 months after DM induction and processed for immunohistochemistry. Results: Diabetic animals showed higher Wnt4 kidney expression both 2 weeks and 2 months post-DM induction, while Snail expression significantly increased only 2 weeks after DM initiation (p < 0.0001). We determined significantly higher expression of examined EMT-related genes in different kidney regions in diabetic animals compared with controls. The most substantial differences were observed in tubular epithelial cells in the period of 2 weeks after induction, with higher Snail and Wnt4 expression in PCT and increased Snail and Notch2 expression in DCT of diabetic animals (p < 0.0001; p < 0.001). Conclusion: The obtained results point to the EMT-related factors Snail, Wnt4, and Notch2 as a potential contributor to diabetic nephropathy development and progression. Changes in their expression, especially in PCT and DCT, could serve as diagnostic biomarkers for the early stages of DM and might be a promising novel therapeutic target in this condition.

Shenkang injection improves chronic kidney disease by inhibiting multiple renin-angiotensin system genes by blocking the Wnt/β-catenin signalling pathway

Chronic kidney disease (CKD) is a major worldwide public health problem. The increase in the number of patients with CKD and end-stage kidney disease requesting renal dialysis or transplantation will progress to epidemic proportions in the next several decades. Although blocking the renin-angiotensin system (RAS) has been used as a first-line standard therapy in patients with hypertension and CKD, patients still progress towards end-stage kidney disease, which might be closely associated with compensatory renin expression subsequent to RAS blockade through a homeostatic mechanism. The Wnt/β-catenin signalling pathway is the master upstream regulator that controls multiple intrarenal RAS genes. As Wnt/β-catenin regulates multiple RAS genes, we inferred that this pathway might also be implicated in blood pressure control. Therefore, discovering new medications to synchronously target multiple RAS genes is necessary and essential for the effective treatment of patients with CKD. We hypothesized that Shenkang injection (SKI), which is widely used to treat CKD patients, might ameliorate CKD by inhibiting the activation of multiple RAS genes via the Wnt/β-catenin signalling pathway. To test this hypothesis, we used adenine-induced CKD rats and angiotensin II (AngII)-induced HK-2 and NRK-49F cells. Treatment with SKI inhibited renal function decline, hypertension and renal fibrosis. Mechanistically, SKI abrogated the increased protein expression of multiple RAS elements, including angiotensin-converting enzyme and angiotensin II type 1 receptor, as well as Wnt1, β-catenin and downstream target genes, including Snail1, Twist, matrix metalloproteinase-7, plasminogen activator inhibitor-1 and fibroblast-specific protein 1, in adenine-induced rats, which was verified in AngII-induced HK-2 and NRK-49F cells. Similarly, our results further indicated that treatment with rhein isolated from SKI attenuated renal function decline and epithelial-to-mesenchymal transition and repressed RAS activation and the hyperactive Wnt/β-catenin signalling pathway in both adenine-induced rats and AngII-induced HK-2 and NRK-49F cells. This study first revealed that SKI repressed epithelial-to-mesenchymal transition by synchronously targeting multiple RAS elements by blocking the hyperactive Wnt/β-catenin signalling pathway.

Combination of mulberry leaf active components possessed synergetic effect on SD rats with diabetic nephropathy by mediating metabolism, Wnt/β-catenin and TGF-β/Smads signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Mulberry leaf has attracted much attention due to its excellent curative effect on diabetes and its complications, whether the combination of its effective components have protective and synergistic effect on diabetic nephropathy (DN) in vivo remain unclear.

AIM OF THE STUDY

The aim of this study was to investigate the protective and synergistic effect of the combination (MAF_1:1 and MAF_1:5) of mulberry leaf alkaloids (MA) and flavonoids extract (MF) on DN.

MATERIALS AND METHODS

A step by step method consisted of network pharmacological prediction, animal in vivo validation and metabolic mechanism research was used to construct the multi-component-target-pathway network of mulberry leaf against DN. Firstly, the potential components and mechanism of mulberry leaf against DN was explored by network pharmacology analysis. Secondly, DN animal model was established to validate the anti-DN activity of these potential compounds. Thirdly, the metabolomics of serum and urine samples from animal experiments was analyzed to explore the anti-DN mechanism of these potential compounds.

RESULTS

The results of network pharmacology demonstrated that a total of 7 compounds detected in MA and MF exhibited anti-DN activity, their mechanism were strongly in connection with metabolic pathways, arachidonic acid metabolism, sphingolipid signaling pathway, etc. The results of animal experiment indicated that MAF_1:1 and MAF_1:5 significantly relieved metabolic disorders through regulating Wnt/β-catenin and TGF-β/Smads signaling pathway, just like MF or MA alone. Metabolomics suggested they could regulate 16 serum and 7 urine endogenous metabolites through arachidonic acid metabolism, phenylalanine metabolism and sphingolipid metabolism, thus alleviated DN. Significantly, MAF_1:1 and MAF_1:5 might possess synergistic effect considering their therapeutic effects on DN rats were superior to the single use of MA or MF.

CONCLUSIONS

MAF_1:1 and MAF_1:5 possessed protective and synergistic effect on DN rats through multi-target and multi-pathways. These findings were of great scientific significance and application value to reveal the advantage of mulberry leaf in preventing and treating DN.

Integrated lipidomics, transcriptomics and network pharmacology analysis to reveal the mechanisms of Danggui Buxue Decoction in the treatment of diabetic nephropathy in type 2 diabetes mellitus

ETHNOPHARMACOLOGICAL RELEVANCE

Danggui Buxue Decoction (DBT) is classical prescriptions, which contains two Traditional Chinese Medicines of Angelicae sinensis radix and Astragali radix. According to the preliminary work of our laboratory and numerous studies, it has been found that DBT has a therapeutic effect on diabetic nephropathy (DN). However, the mechanisms underlying its action remain unclear.

AIM OF THE STUDY

The aim of this study was to evaluate the impact of DBT on kidney disease in diabetic mice and further explore its protective mechanism.

METHODS

DN mice model was induced by high-fat fodder and streptozotocin (STZ). Qualitative and quantitative analysis of 6 compounds in DBT was carried out by HPLC, including calycosin-7-glucoside, ferulic acid, ononin, calycosin, formononetin, and levostilide A. Hematoxylin-Eosin (HE) staining was used to determine the degree of kidney pathological damage. The UPLC-Q Exactive MS technique was used to analyze the lipids metabolism profile of kidneys samples and multiple statistical analysis methods were used to screen and identify biomarkers. Transcriptomics analyses were carried out using RNAseq. The possible molecular mechanism was unraveled by network pharmacology.

RESULTS

Thirty-one significantly altered lipid metabolites were identified in the model group comparing with the control group. DBT improved aberrant expression of several pathways related to lipidomics, including glycerophospholipid metabolism and sphingolipid metabolism. Comprehensive analysis indicated that DBT intervention reduced the content of Cers, phosphatidylethanolamines and phosphatidylcholines in mouse kidneys by downregulating the transcription level of Degs2 and Cers, reducing lipid accumulation and promoting Akt phosphorylation by upregulating the expression of Acers and Pdk1. Network pharmacology analysis showed that components in DBT, such as kaempferol, ferulic acid and astragaloside IV, could be responsible for the pharmacological activity of DN by regulating the AGE-RAGE, PI3K/Akt, MAPK and NF-κB signaling pathways in diabetic complications.

CONCLUSIONS

These results showed that DBT may improve DN by affecting insulin resistance, chronic inflammation and lipid accumulation.

Salvia spinosa L. Protects against Diabetes-Induced Nephropathy by Attenuation of Mitochondrial Oxidative Damage in Mice

Mitochondrial oxidative damage is a crucial factor in the pathogenesis of diabetic nephropathy (DN), which is among the most prevalent problems of diabetes, and there hasn't been an effective treatment for DN yet. This study planned to investigate the effects of Salvia spinosa L. on mitochondrial function along with its protection against streptozotocin-induced nephropathy in diabetic mice. After the injection of streptozotocin (STZ) and verification of the establishment of diabetes, mice (n = 30) were randomly divided into the following groups: control group, diabetic-control, S. spinosa-treated diabetic (50, 100, and 200 mg/kg), and metformin-treated diabetic group (500 mg/kg). After four weeks of treatment, the mice were weighed. Blood and kidney tissues were examined for biochemical and histological evaluation. Hematoxylin and eosin staining was used for evaluating renal pathologic damage. Oxidative damage in the kidney was assessed by the evaluation of lipid peroxidation and glutathione oxidation. Furthermore, differential centrifugation was used to obtain the isolated mitochondria, and mitochondrial toxicity endpoints (mitochondrial function and mitochondrial oxidative markers) were determined in them. S. spinosa remarkably reduced the blood urea and creatinine concentrations, and also normalized kidney weight/body weight coefficient in the diabetic mice. S. spinosa ameliorated the incidence of glomerular and tubular pathological changes in histological analyses. Moreover, the oxidative and mitochondrial damages were notably attenuated in renal tissues of S. spinosa-treated mice. These results indicate that the methanolic extract of S. spinosa modulates the nephropathy in the diabetic mice by the amelioration of oxidatively induced mitochondrial damage and provides a reliable scientific base, suggesting S. spinosa as a promising alternative remedy against DN.

Deciphering the Pharmacological Mechanisms of Qidan Dihuang Decoction in Ameliorating Renal Fibrosis in Diabetic Nephropathy through Experimental Validation In Vitro and In Vivo

OBJECTIVE

QiDan DiHuang decoction (QDD) has been proven to have good efficacy in decreasing albuminuria levels, improving renal function, and inhibiting renal fibrosis in diabetic nephropathy (DN). However, the potential mechanism remains unclear. The purpose of this study was to explore the underlying mechanism of QDD for treating DN in vitro and in vivo.

METHODS

Db/db mice were treated with QDD or saline intragastrically for 12 weeks. Non-diabetic db/m mice were used as controls. Rat renal tubular epithelial cells (NRK-52E) were cultured in high glucose conditions. ATF4 siRNA was transfected into NRK-52E cells. Different indicators were detected via UPLC, RT-PCR, western blotting, cell viability assays and apoptosis, transmission electron microscopy, histology, and immunofluorescence staining.

RESULTS

Db/db mice experienced severe kidney damage and fibrosis, increased levels of PERK, eIF2α, and ATF4, and suppression of renal autophagy compared with db/m mice. The results showed a significant improvement in glucose intolerance, blood urea nitrogen, urine albumin, serum creatinine, and renal fibrosis in db/db mice with QDD treatment. Meanwhile, the application of QDD resulted in the downregulation of PERK, eIF2α, and ATF4 and the upregulation of autophagy in diabetic kidneys. In vitro, the exposure of NRK-52E cells to high glucose resulted in downregulation of the ratio of LC3-II/LC3-I and upregulation of P62, a reduction in the number of autophagosomes and upregulation of fibronectin (FN), collagen IV and TGF-β1 protein, which was reversed by QDD treatment through inhibiting ATF4 expression.

CONCLUSIONS

Taken together, our results suggest that QDD effectively alleviates diabetic renal injuries and fibrosis by inhibiting the PERK-eIF2α-ATF4 pathway and promoting autophagy in diabetic nephropathy.

Therapeutic DNA vaccine encoding CEMIP (KIAA1199) ameliorates kidney fibrosis in obesity through inhibiting the Wnt/β-catenin pathway

BACKGROUND

CEMIP is a novel risk factor of various cancers through activating Wnt/β-catenin /epithelial-mesenchymal transition between epithelial cells and stroma. The chronic fibrosis commonly contributes renal carcinogenesis in patients with obesity. As there have very few choices of medicines targeting CEMIP. This study intended to design therapeutic DNA vaccines for nephropathy in obesity, through diminishing the CEMIP/Wnt1/β-catenin pathway.

METHOD

In an 8-week experiment, plasmid-encoding CEMIP was vaccinated into high-fat diet (HFD) or obesity mice in the first 4 weeks, and then vaccination was stopped for at least 4 weeks. Then, plasma and spleens were harvested to evaluate anti-CEMIP antibody synthesis and T-helper type 1 and 2 activation after vaccination. Kidneys were collected to investigate efficacy of CEMIP DNA vaccine on inhibiting HFD and obesity-induced fibrosis and Wnt1/β-catenin pathway. To confirm that CEMIP crucially contributed towards fibrotic formation, CEMIP gene or siRNA transfection was performed in HK-2 cells under VLDL stimulation, or not.

RESULTS

At the end point, anti-CEMIP antibody was successfully produced in the pcDNA 3.1-CEMIP vaccinated group, while Wnt1/β-catenin signaling and fibrosis was inactive. Through VLDL stimulation and CEMIP overexpression, Wnt1/β-catenin signaling and fibrosis significantly presented in vitro. Otherwise, anti-sera of CEMIP-vaccinated mice could inhibit the VLDL-induced Wnt1/β-catenin/fibrosis pathway in HK-2 cells. Similarly, the silencing of CEMIP by siRNA ameliorated the Wnt1/β-catenin pathway and fibrogenesis under VLDL stimulation.

CONCLUSION

DNA vaccine targeting CEMIP/Wnt1/β-catenin pathway plays a novel strategy in nephropathy.

GENERAL SIGNIFICANCE

Immune therapy might provide a new therapeutic option on nephropathy of obesity.

Metabolic Profiling of Carbonyl Compounds for Unveiling Protective Mechanisms of Pueraria lobata against Diabetic Nephropathy by UPLC-Q-Orbitrap HRMS/MS Analysis

Carbonyl compounds play a critical role in the pathogenesis of diabetic nephropathy (DN). Pueraria lobata (PL), also known as "Kudzu", is a widely consumed functional food or nutraceutical and has shown promise in the prevention of diabetes and complications such as DN. To explore the beneficial effects and the underlying mechanisms of PL against DN, a new strategy for in-depth metabolic profiling of carbonyl compounds in DN mice plasma by chemical derivatization combined with UPLC-Q-Orbitrap high-resolution mass spectrometry (HRMS)/MS analysis was developed for the first time. Pharmacological evaluation revealed that PL extracts containing a total of 73 identified compounds could ameliorate kidney injury and regulate abnormal glycolipid metabolism. In metabolomics analysis, 19 carbonyl compounds with significant differences were identified between DN mice and normal mice. Moreover, 12 metabolites had a tendency to return to normal levels after PL treatment. Overall, PL exerts beneficial effects on DN by regulating abnormal glycolipid metabolism and carbonyl stress, and endogenous carbonyl compounds might serve as potential biomarkers for DN.

Targeting the Wnt/β-Catenin Signaling Pathway as a Potential Therapeutic Strategy in Renal Tubulointerstitial Fibrosis

The Wnt/β-catenin signaling pathway plays important roles in embryonic development and tissue homeostasis. Wnt signaling is induced, and β-catenin is activated, associated with the development and progression of renal fibrosis. Wnt/β-catenin controls the expression of various downstream mediators such as snail1, twist, matrix metalloproteinase-7, plasminogen activator inhibitor-1, transient receptor potential canonical 6, and renin-angiotensin system components in epithelial cells, fibroblast, and macrophages. In addition, Wnt/β-catenin is usually intertwined with other signaling pathways to promote renal interstitial fibrosis. Actually, given the crucial of Wnt/β-catenin signaling in renal fibrogenesis, blocking this signaling may benefit renal interstitial fibrosis. There are several antagonists of Wnt signaling that negatively control Wnt activation, and these include soluble Fzd-related proteins, the family of Dickkopf 1 proteins, Klotho and Wnt inhibitory factor-1. Furthermore, numerous emerging small-molecule β-catenin inhibitors cannot be ignored to prevent and treat renal fibrosis. Moreover, we reviewed the knowledge focusing on anti-fibrotic effects of natural products commonly used in kidney disease by inhibiting the Wnt/β-catenin signaling pathway. Therefore, in this review, we summarize recent advances in the regulation, downstream targets, role, and mechanisms of Wnt/β-catenin signaling in renal fibrosis pathogenesis. We also discuss the therapeutic potential of targeting this pathway to treat renal fibrosis; this may shed new insights into effective treatment strategies to prevent and treat renal fibrosis.

Non-invasive metabolic biomarkers for early diagnosis of diabetic nephropathy: Meta-analysis of profiling metabolomics studies

AIM

Diabetic nephropathy (DN) is one of the worst complications of diabetes. Despite a growing number of DN metabolite profiling studies, most studies are suffering from inconsistency in their findings. The main goal of this meta-analysis was to reach to a consensus panel of significantly dysregulated metabolites as potential biomarkers in DN.

DATA SYNTHESIS

To identify the significant dysregulated metabolites, meta-analysis was performed by "vote-counting rank" and "robust rank aggregation" strategies. Bioinformatics analyses were performed to identify the most affected genes and pathways. Among 44 selected studies consisting of 98 metabolite profiles, 17 metabolites (9 up-regulated and 8 down-regulated metabolites), were identified as significant ones by both the meta-analysis strategies (p-value<0.05 and OR>2 or <0.5) and selected as DN metabolite meta-signature. Furthermore, enrichment analyses confirmed the involvement of various effective biological pathways in DN pathogenesis, such as urea cycle, TCA cycle, glycolysis, and amino acid metabolisms. Finally, by performing a meta-analysis over existing time-course studies in DN, the results indicated that lactic acid, hippuric acid, allantoin (in urine), and glutamine (in blood), are the topmost non-invasive early diagnostic biomarkers.

CONCLUSION

The identified metabolites are potentially involved in diabetic nephropathy pathogenesis and could be considered as biomarkers or drug targets in the disease.

PROSPERO REGISTRATION NUMBER

CRD42020197697.

An Overview of the Posttranslational Modifications and Related Molecular Mechanisms in Diabetic Nephropathy

Diabetic nephropathy (DN), a common diabetic microvascular complication, is characterized by its complex pathogenesis, higher risk of mortality, and the lack of effective diagnosis and treatment methods. Many studies focus on the diagnosis and treatment of diabetes mellitus (DM) and have reported that the pathophysiology of DN is very complex, involving many molecules and abnormal cellular activities. Given the respective pivotal roles of NF-κB, Nrf2, and TGF-β in inflammation, oxidative stress, and fibrosis during DN, we first review the effect of posttranslational modifications on these vital molecules in DN. Then, we describe the relationship between these molecules and related abnormal cellular activities in DN. Finally, we discuss some potential directions for DN treatment and diagnosis. The information reviewed here may be significant in the design of further studies to identify valuable therapeutic targets for DN.

The complex role of Wnt ligands in type 2 diabetes mellitus and related complications

Type 2 diabetes mellitus (T2DM) is one of the major chronic diseases, whose prevalence is increasing dramatically worldwide and can lead to a range of serious complications. Wnt ligands (Wnts) and their activating Wnt signalling pathways are closely involved in the regulation of various processes that are important for the occurrence and progression of T2DM and related complications. However, our understanding of their roles in these diseases is quite rudimentary due to the numerous family members of Wnts and conflicting effects via activating the canonical and/or non-canonical Wnt signalling pathways. In this review, we summarize the current findings on the expression pattern and exact role of each human Wnt in T2DM and related complications, including Wnt1, Wnt2, Wnt2b, Wnt3, Wnt3a, Wnt4, Wnt5a, Wnt5b, Wnt6, Wnt7a, Wnt7b, Wnt8a, Wnt8b, Wnt9a, Wnt9b, Wnt10a, Wnt10b, Wnt11 and Wnt16. Moreover, the role of main antagonists (sFRPs and WIF-1) and coreceptor (LRP6) of Wnts in T2DM and related complications and main challenges in designing Wnt-based therapeutic approaches for these diseases are discussed. We hope a deep understanding of the mechanistic links between Wnt signalling pathways and diabetic-related diseases will ultimately result in a better management of these diseases.

Salviae miltiorrhizae and ligustrazine hydrochloride injection combined with mecobalamin for treating diabetic peripheral neuropathy: A protocol for systematic review and meta-analysis

OBJECTIVE

Currently, it is unclear whether the salviae miltiorrhizae (Danshen Salvia) and ligustrazine hydrochloride (Chuanxiong Chuanxiong) (SMLH) injection combined with mecobalamin can improve diabetic peripheral neuropathy (DPN). We conducted a systematic analysis to evaluate the clinical effects of SMLH injection combined with mecobalamin for treating DPN.

METHODS

Seven databases, including PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wan Fang Database (Wang Fang), Chinese Biomedical Literature Database (CBM), and VIP Database for Chinese Technical Periodicals (VIP) were searched for systematic literature retrieval. Each database was searched up to 2020 to identify randomized controlled trials on DPN treated with SMLH injection combined with mecobalamin. We used the RevMan 5.3 and Stata 14.0 software to assess the risk of bias in the included trials.

RESULTS

A total of 15 publications, including 1349 samples, were reviewed. The total effective rate of SMLH injection combined with mecobalamin was 31% higher than that of mecobalamin alone (95% confidence interval [CI] = 1.23-1.38; P < .00001). The experimental group showed a significant increase in the motor conduction velocity (MCV) of the peroneal nerve (weighted mean difference [WMD] = 4.81, 95% CI 3.53-6.09; P < .00001). In addition, SMLH injection combined with mecobalamin showed a statistical significant effect on the sensory conduction velocity (SCV) of the peroneal nerve (WMD = 5.03, 95% CI = 4.16-5.90; P < .00001), and MCV of the median nerve (WMD = 5.38, 95% CI = 4.05-6.72; P < .00001). The WMD for the change in SCV in the median nerve was 4.89 m/s (95% CI = 3.88-5.89; P < .00001). The P-values of the Egger and Begg tests were 0.967 and 0.961, respectively, indicating no publication bias. Subgroup and sensitivity analyses indicated that the results for MCV and SCV of the peroneal nerve and the median nerve were stable.

CONCLUSION

SMLH injection combined with mecobalamin can improve DPN, compared with mecobalamin alone.

Salvianolic Acid B Protects Against Fatty Acid-Induced Renal Tubular Injury via Inhibition of Endoplasmic Reticulum Stress

Background/Aims: Obesity-related kidney disease is associated with elevated levels of saturated free fatty acids (SFA). SFA lipotoxicity in tubular cells contributes to significant cellular apoptosis and injury. Salvianolic acid B (SalB) is the most abundant bioactive molecule from Radix Salviae Miltiorrhizae. In this study, we investigated the effect of SalB on SFA-induced renal tubular injury and endoplasmic reticulum (ER) stress, in vivo and in vitro. Methods: C57BL/6 mice were assigned to five groups: a control group with normal diet (Nor), high-fat diet group (HFD), and HFD with three different SalB treatment doses, low (SalBL; 3 mg/kg), medium (SalBM; 6.25 mg/kg), and high (SalBH; 12.5 mg/kg) doses. SalB was intraperitoneally injected daily for 4 weeks after 8 weeks of HFD. After 12 weeks, mice were sacrificed and kidneys and sera were collected. Apoptosis and ER stress were induced in human proximal tubule epitelial (HK2) cells by palmitic acid (PA, 0.6 mM), tunicamycin (TM, 1 μg/ml), or thapsigargin (TG, 200 nM) in vitro. Results: C57BL/6 mice fed a high-fat diet (HFD) for 12 weeks exhibited increased apoptosis (Bax and cleaved caspase-3) and ER stress (BIP, P-eIF2α, ATF4, CHOP, ATF6, IRE1α, and XBP1s) markers expression in the kidney, compared with control mice, which were remarkably suppressed by SalB treatment. In vitro studies showed that PA (0.6 mM) induced apoptosis and ER stress in cultured HK2 cells. SalB treatment attenuated all the adverse effects of PA. However, SalB failed to inhibit TM or TG-induced ER stress in HK2 cells. Conclusion: The study indicated that SalB may play an important role in obesity-related kidney injury via mediating SFA-induced ER stress.

The pathogenesis of renal injury in obstructive jaundice: A review of underlying mechanisms, inducible agents and therapeutic strategies

Kidney injury is one of the main complications of obstructive jaundice (OJ) and its pathogenesis has not been clarified. As an independent risk factor for OJ associated with significant morbidity and mortality, it can be mainly divided into two types of morphological injury and functional injury. We called these dysfunctions caused by OJ-induced kidney injury as OJKI. However, the etiology of OJKI is still not fully clear, and research studies on how OJKI becomes a facilitated factor of OJ are limited. This article reviews the underlying pathological mechanism from five aspects, including metabolisms of bile acids, hemodynamic disturbances, oxidative stress, inflammation and the organic transporter system. Some nephrotoxic drugs and measures that can enhance or reduce the renal function with potential intervention in perioperative periods to alleviate the incidence of OJKI were also described. Furthermore, a more in-depth study on the pathogenesis of OJKI from multiple aspects for exploring more targeted treatment measures were further put forward, which may provide new methods for the prevention and treatment of clinical OJKI and improve the prognosis.

Mefunidone ameliorates diabetic kidney disease in STZ and db/db mice

Diabetic kidney disease (DKD) is a major cause of end stage renal diseases worldwide. Despite successive interventions for delaying the progression of DKD, current treatments cannot reverse the pathological progression. Mefunidone (MFD) is a new compound with potent antifibrotic properties, but the effect of MFD on DKD remains unknown. Therefore, we investigated the protective effects of MFD in both models of the db/db type 2 diabetes (T2D) and streptozotocin (STZ)-induced type 1 diabetes (T1D) models. Compared with the model group, MFD treatment significantly reduced pathological changes observed by PAS staining, PASM staining, and Masson staining in vivo. To further elucidate the potential mechanisms, we discovered MFD treatment notably restored podocyte function, alleviated inflammation, abated ROS generation, inhibited the TGF-β1/SAMD2/3 pathway, suppressed the phosphorylation levels of MAPKs (ERK1/2, JNK, and P38), and reduced epithelial-to-mesenchymal transition(EMT). In conclusion, these findings demonstrate the effectiveness of MFD in diabetic nephropathy and elucidate its possible mechanism.

Celastrol slows the progression of early diabetic nephropathy in rats via the PI3K/AKT pathway

Background

Diabetic nephropathy serves as one of the most regular microvascular complications of diabetes mellitus and is the main factor that causes end-stage renal disease and incident mortality. As the beneficial effect and minute adverse influence of Celastrol on the renal system requires further elucidation, the renoprotective function of Celastrol in early diabetic nephropathy was investigated.

Methods

In high-fat and high-glucose diet/streptozotocin-induced diabetic rats which is the early diabetic nephropathy model, ALT, AST, 24 h urinary protein, blood urea nitrogen, and serum creatinine content were observed. Periodic acid-Schiff staining, enzyme-linked immunosorbent assay, immunohistochemical analysis, reverse transcription-polymerase chain reaction, and western blot analysis were used to explore the renoprotective effect of Celastrol to diabetic nephropathy rats and the underlying mechanism.

Results

High dose of Celastrol (1.5 mg/kg/d) not only improved the kidney function of diabetic nephropathy (DN) rats, and decreased the blood glucose and 24 h urinary albumin, but also increased the expression of LC3II and nephrin, and downregulated the expression of PI3K, p-AKT, and the mRNA level of NF-κB and mTOR.

Conclusion

Celastrol functions as a potential therapeutic substance, acting via the PI3K/AKT pathway to attenuate renal injury, inhibit glomerular basement membrane thickening, and achieve podocyte homeostasis in diabetic nephropathy.

Poricoic acid A as a modulator of TPH-1 expression inhibits renal fibrosis via modulating protein stability of β-catenin and β-catenin-mediated transcription

Background

Renal fibrosis is the common feature of chronic kidney disease (CKD). However, few drugs specifically target fibrogenesis due to the lack of an effective therapeutic target. Hence, it is urgent to find a therapeutic strategy that inhibits renal fibrosis. Here, we identified that poricoic acid A (PAA) as the modulator of tryptophan hydroxylase-1 (TPH-1), the key enzyme in tryptophan metabolism, exerted potent anti-fibrotic effects in the kidney.

Methods

Lentiviral vector, luciferase reporter activity assay and co-immunoprecipitation were used. The animal model of unilateral ureteral obstruction and adenine-induced chronic renal failure as well as transforming growth factor (TGF)-β1-treated epithelial cells NRK-52E and fibroblasts NRK-49F were used.

Results

TPH-1 was gradually decreased during CKD progression, while PAA treatment significantly increased TPH-1 expression to suppress renal fibrosis. Pharmacological overexpression of TPH-1 by PAA treatment exhibited anti-fibrosis and was linked to Wnt/β-catenin signaling activity. TPH-1 exhibited anti-fibrotic effects by suppressing epithelial cell injury and fibroblast activation, and PAA promoted TPH-1 expression and then suppressed the Wnt/β-catenin signaling pathway via regulating the protein stability of β-catenin and β-catenin-mediated transcription. TPH-1 overexpression enhanced the anti-fibrotic effects of PAA, while TPH-1 deficiency weakened the anti-fibrotic effects of PAA, indicating that TPH-1 was required for the anti-fibrotic effects of PAA.

Conclusion

PAA as a modulator of TPH-1 expression attenuated renal fibrosis through regulating the Wnt/β-catenin signaling pathway by acting on the protein stability of β-catenin and β-catenin-mediated transcription. TPH-1 was required for PAA to exert anti-fibrosis.

Wnt signaling pathway in aging-related tissue fibrosis and therapies

Fibrosis is the final hallmark of pathological remodeling, which is a major contributor to the pathogenesis of various chronic diseases and aging-related organ failure to fully control chronic wound-healing and restoring tissue function. The process of fibrosis is involved in the pathogenesis of the kidney, lung, liver, heart and other tissue disorders. Wnt is a highly conserved signaling in the aberrant wound repair and fibrogenesis, and sustained Wnt activation is correlated with the pathogenesis of fibrosis. In particular, mounting evidence has revealed that Wnt signaling played important roles in cell fate determination, proliferation and cell polarity establishment. The expression and distribution of Wnt signaling in different tissues vary with age, and these changes have key effects on maintaining tissue homeostasis. In this review, we first describe the major constituents of the Wnt signaling and their regulation functions. Subsequently, we summarize the dysregulation of Wnt signaling in aging-related fibrotic tissues such as kidney, liver, lung and cardiac fibrosis, followed by a detailed discussion of its involvement in organ fibrosis. In addition, the crosstalk between Wnt signaling and other pathways has the potential to profoundly add to the complexity of organ fibrosis. Increasing studies have demonstrated that a number of Wnt inhibitors had the potential role against tissue fibrosis, specifically in kidney fibrosis and the implications of Wnt signaling in aging-related diseases. Therefore, targeting Wnt signaling might be a novel and promising therapeutic strategy against aging-related tissue fibrosis.

Salvia miltiorrhiza stem-leaf active components of salvianolic acids and flavonoids improved the hemorheological disorder and vascular endothelial function on microcirculation dysfunction rats

Microcirculation, which connects macrocirculation and cells between arterioles and venules, plays a major role in the early onset of a variety of diseases. In this article, a dextran-induced microcirculation dysfunction (MCDF) model rats were adopted to evaluate the effects and mechanism of Salvia miltiorrhiza stem-leaf extracts based on plasma and urine metabonomics. The results showed the effective components of S. miltiorrhiza stem-leaf could significantly improve the hemorheology and coagulation index of MCDF rats and callback the expression of endothelin-1 (ET-1), induciblenitric oxide synthase (iNOS), vascularendothelial growth factor (VEGF), P-Selectin, thromboxane A2, 6-keto-PGF_1α , TNF-α, and interleukin-1β to control group in MCDF rats. The decrease of microvessel density (MVD) in lung and thymus caused by MCDF was upgraded by Salvia miltiorrhiza stem-leaf. Based on the plasma and urine metabolic data, 20 potential biomarkers were identified. These biomarkers are mainly related to linoleic acid metabolism, glutathione metabolism, pantothenate and coenzyme A biosynthesis, pentose and glucuronate interconversions, pyruvate metabolism, glyoxylate and dicarboxylate metabolism, beta-alanine metabolism, and citrate cycle. The results indicated that the effective components of S. miltiorrhiza stem-leaf can improve the hemorheological disorder and vascular endothelial function. Meanwhile, the effective components can regulate potential biomarkers and correlated metabolic pathway, which can provide guidance for the research and development of new drugs for MCDF.

2-Dodecyl-6-methoxycyclohexa-2,5-diene-1,4-dione, isolated from the root of Averrhoa carambola L., protects against diabetic kidney disease by inhibiting TLR4/TGFβ signaling pathway

OBJECTIVE

Diabetic kidney disease (DKD) is the leading cause of death and disability of diabetes mellitus. However, there is still a lack of specific drugs for the treatment of DKD. The chief aim of this research is to investigate the role and mechanism of 2-Dodecyl-6-methoxycyclohexa-2,5-diene-1,4-dione (DMDD) for DKD.

METHODS

Wild type and TLR4 knockout mice were induced to diabetes. After 4-week treatment with DMDD, blood sugar, renal function, blood lipid and pathological changes were assessed. Real-time PCR, western blotting, and immunohistochemistry were employed to detect the expressions of TLR4, TGFβ1 and Smad2/3 in the renal tissue.

RESULTS

DMDD improved the serum lipid and decreased fasting blood glucose levels in diabetic mice. CysC and urinary albumin levels increased markedly in the diabetic group, and they were obviously decreased after 4 weeks of DMDD treatment. Compared with the WT diabetic mice, the urinary albumin and CysC in the TLR4-/- mice were expressed at lower levels. HE and Masson's staining revealed that DMDD clearly ameliorated pathological changes and renal fibrosis. When TLR4 gene was knock out, the pathological was improved. Mechanistically, TLR4, TGF-β1 and Smad2/3 were obvious up-regulation in the renal tissues of diabetic mice. The expressions of these proteins were significantly down-regulated after DMDD treatment (p < 0.05). In the TLR4-/- mice, mRNA and protein levels of TGF-β1 and Smad2/3 were obviously lower than those in the WT mice. In addition, IHC revealed that a strong in situ expressions of TLR4, TGF-β1 and Smad2/3 were seen in the kidney tissues of diabetic mice, which were distinctly weakened in the DMDD-treated mice. In the TLR4-/- mice, however, expressions of TGF-β1 and Smad2/3 were not remarkable increase in the diabetic mice compared with normal mice.

CONCLUSIONS

These results strongly indicate that TLR4 is essential for DMDD protection against renal dysfunction in diabetic mice. Its hypoglycemic and anti-fibrosis effects were likely mediated by the TLR4/TGFβ signaling pathway.

A Novel Antidiabetic Monomers Combination Alleviates Insulin Resistance Through Bacteria-Cometabolism-Inflammation Responses

The present study sought to examine the therapeutic effect of a novel antidiabetic monomer combination (AMC) in treating type 2 diabetes mellitus (T2DM); while also elucidating the potential functional mechanism. Male C57BL/6J mice were fed a high-fat diet (HFD) for 12 weeks to establish T2DM. The AMC group showed significant reduction in weight, fasting blood glucose (FBG), serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C), and experienced reduced insulin resistance based on oral glucose tolerance testing (OGTT) and hyperinsulinemic-euglycemic clamp testing (“gold standard” for determining in vivo insulin sensitivity). Further, AMC restored the altered intestinal flora by increasing the abundance of the beneficial bacteria Akkermansia, and decreasing the number of harmful bacteria, including Bacteroides, Odoribacter, Prevotella 9, Alistipes, and Parabacteroides. Components of the host-microbial metabolome were also significantly changed in the AMC group compared to the HFD group, including hydroxyphenyllactic acid, palmitoleic acid, dodecanoic acid, linoleic acid, and erucic acid. Furthermore, AMC was found to inhibit inflammation and suppress signaling pathways related to insulin resistance. Lastly, spearman correlation analysis revealed relationships between altered microbial community and co-metabolite levels, co-metabolites and inflammatory cytokines. Hence, the potential mechanism responsible for AMC-mediated alleviation of insulin resistance was suggested to be involved in modulation of bacteria-cometabolism-inflammation responses.

Pharmacological potential of the combination of Salvia miltiorrhiza (Danshen) and Carthamus tinctorius (Honghua) for diabetes mellitus and its cardiovascular complications

Metabolic syndrome, such as diabetes mellitus, obesity, atherosclerosis, and high blood pressure (HBP), are closely linked pathophysiologically. However, current monotherapies for metabolic syndrome fail to target the multifactorial pathology via multiple mechanisms, as well as resolving the dysfunctionality of the cells and organs of the body. We aimed to provide a comprehensive and up-to-date review of the pharmacological advances, therapeutic potential, and phytochemistry of Salvia miltiorrhiza, Carthamus tinctorius, and Danhong injection (DHI). We discussed the molecular mechanisms of the bioactive constituents relating to diabetes mellitus and metabolic disease for further research and drug development. Interestingly, Salvia miltiorrhiza, Carthamus tinctorius, and DHI have anti-inflammatory, anti-glycemic, anti-thrombotic, and anti-cancer properties; and they mainly act by targeting the dysfunctional vasculatures including the inflammatory components of the disease to provide vascular repair as well as resolving oxidative stress. The major bioactive chemical constituents of these plants include polyphenolic acids, diterpene compounds, carthamin, and hydroxysafflor yellow A. Treatment of diabetes mellitus and its associated cardiovascular complication requires a comprehensive approach involving the use of appropriate traditional Chinese medicine formula. Danshen, Honghua, and DHI target the multiple risk factors regulating the physiologic function of the body and restore normalcy, apart from the traditional advice on exercise and diet control as treatment options in a metabolic syndrome patient.

Lycium barbarum L. leaves ameliorate type 2 diabetes in rats by modulating metabolic profiles and gut microbiota composition

The leaf of Lycium barbarum L. (LLB) has been widely used as a tea, vegetable, and herb in China and Southeast Asia for centuries; this is because of the hypoglycemic effect it has, but the mechanism behind this effect is still unclear. In this study, a type 2 diabetic mellitus (T2DM) rat model, induced by a high-fat diet combined with low-dose streptozotocin (STZ) injections, was adopted. The biochemical index was determined and the histopathological and metabolomics analyses of serum and urine and 16S rDNA sequencing of the gut microbiota were performed. We evaluated the hypoglycemic effects and the mechanism of action of the water extract from LLB, which contained neochlorogenic acid, chlorogenic acid, caffeic acid, and rutin (up to 6.06%). The relationships between biochemical indexes, serum and urine metabolites, and gut microbiota were analyzed. The results showed that the LLB extract could noticeably modulate the levels of blood glucose and lipids in diabetic rats as well as repair injuries in livers, kidneys and pancreas. The changes in serum and urine metabolites caused by T2DM were reversed after the administration of LLB; these changes were found to mainly be correlated with the following pathways: nicotinate and nicotinamide metabolism, arachidonic acid metabolism, and purine metabolism. Sequencing of the 16S rDNA from fecal samples showed that the LLB extract could reverse the gut microbiota dysbiosis that T2DM had induced. Therefore, we conclude that T2DM, which altered the metabolic profiles and gut microbiota, could be alleviated effectively using the LLB extract.

Effects of Bailing capsule on diabetic nephropathy based on UPLC-MS urine metabolomics

Diabetic nephropathy (DN) is one of the most common microvascular diabetes complications and has become a threat to human health. Bailing capsules (BLCs), containing fermentation products of Cordyceps sinensis, have been commonly used for treatment of renal dysfunction, such as DN. However, mechanisms underlying the protective effects of BLC remain largely obscure and await more investigation. In this study, UPLC-MS-based comprehensive metabolomics along with pattern recognition was applied to explore the urine metabolic alteration of DN as well as therapeutic mechanisms of BLC. Nineteen differentially expressed endogenous metabolites were identified related to DN, which were involved in the perturbations of tyrosine metabolism, tryptophan metabolism, glycine metabolism, purine metabolism, glutamine metabolism, phenylalanine metabolism, histidine metabolism and TCA cycle metabolism pathways. After drug intervention, most of the biomarkers exhibited a certain extent towards normal levels (P < 0.05), which indicated that BLC was an effective drug for treating DN and might play its therapeutic role by retrieving abnormal metabolism pathways. The data obtained in this research may pave the way for further exploration of DN and provide key clues to understand the protective effect of BLC.

UPLC-MS-based metabolomics along with pattern recognition was applied to explore the metabolic alteration of diabetic nephropathy and therapeutic mechanisms of Bailing capsule.

The TGF-β/Smad Pathway Inhibitor SB431542 Enhances The Antitumor Effect Of Radiofrequency Ablation On Bladder Cancer Cells

Background

Despite progress achieved in bladder cancer (BC) treatment, the prognosis of patients with advanced BC (ie, metastasized from the bladder to other organs) is poor. Although mortality in cases of low-grade BC is rare, the treatment, such as a radical cystectomy, often has a serious impact on the quality of life. Thus, research is needed to identify more effective treatment strategies and this work is aiming to examine the potential application of combination of radiofrequency ablation (RFA) and SB435142, a inhibitor of transforming growth factor β (TGFβ)/Smad pathway.

Methods

BC cells were transplanted into nude mice (thymusdeficiency Bal B/c) to form subcutaneous tumors. The mice with subcutaneous tumors were then treated with RFA and oral administration of SB431542, an inhibitor of TGFβ/Smad signaling pathway. The antitumor effect of RFA was measured by tumor proliferation curves and micro-positron emission computed tomography (micro-PET). The effect of SB431542 on epithelial-mesenchymal transition (EMT) related regulators in subcutaneous tumor tissues formed by BC cells were examined by quantitative real-time polymerase chain reaction (qPCR) experiments.

Results

The SB431542 treatment enhanced the antitumor effect of RFA on subcutaneous growth of BCs. SB431542 also decreased EMT-related regulators in subcutaneous tumor tissues formed by BC cells in nude mice.

Conclusion

SB431542 enhances the effect of RFA on BC.

Chelidonine enhances the antitumor effect of lenvatinib on hepatocellular carcinoma cells

Background

Lenvatinib is a newly approved molecular targeted drug for the treatment of advanced hepatocellular carcinoma (HCC). However, the high cost associated with this treatment poses a huge financial burden on patients and the entire public health system. Therefore, there is an urgent need to develop novel strategies that enhance the antitumor effect of lenvatinib.

Methods

The antitumor effects of chelidonine or/and lenvatinib on HCC cell lines MHCC97-H and LM-3 were examined using the 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2- H-tetrazolium bromide (MTT) assay. For the in-vivo investigation, the effect on subcutaneous or intrahepatic tumor growth in nude mice was also determined. The mRNA levels of epithelial mesenchymal transition (EMT)-related factors were examined through quantitative polymerase chain reaction or Western blot.

Results

In the present study, we found that treatment with chelidonine enhanced the apoptotic effect of lenvatinib on HCC cells and the in-vivo growth of HCC tumors in nude mice. Mechanistically, treatment with chelidonine increased the expression of epithelial indicator E-cadherin, whereas it decreased the expression of mesenchymal indicators N-cadherin and Vimentin. These findings suggest that chelidonine restricted the EMT in HCC cells.

Conclusion

Chelidonine inhibits the process of EMT and enhances the antitumor effect of lenvatinib on HCC cells.

Hirsutella sinensis Treatment Shows Protective Effects on Renal Injury and Metabolic Modulation in db/db Mice

Hirsutella sinensis (HS) is the anamorph of the traditional Chinese medicine Cordyceps sinensis. Although the renal protective effect of HS has been reported, its effect on diabetic nephropathy (DN) remains unclear. In this study, db/db mice were used as the DN model, and the renal protective effect was evaluated after oral administration of HS for 6 and 12 weeks. Plasma, urine, and kidney samples were collected, and biochemical indicator measurements, pathological analysis, and metabolomics studies were performed. Biochemical assays showed that HS reduced the levels of fasting blood glucose (FBG), urinary albumin/creatinine ratio (ACR), and N-acetyl-beta-D-glucosaminidase (NAG) and increased the creatinine clearance (Ccr). HS alleviated glomerular and tubular glycogen accumulation and fibrosis and normalized the disordered ultrastructure of the glomerular filtration barrier. Metabolomics analysis of metabolites in the plasma, urine, and kidney indicated that HS modulated the perturbed glycolipid metabolism and amino acid turnover. HS reduced the elevated levels of metabolites involved in energy metabolism (TCA cycle, glycolysis, and pentose phosphate pathway) and nucleotide metabolism (pyrimidine metabolism and purine metabolism) in the kidneys of db/db mice. These results suggest that HS can protect against renal injury and that its efficacy involved metabolic modulation of the disturbed metabolome in db/db mice.

The Efficacy and Mechanism of Chinese Herbal Medicine on Diabetic Kidney Disease

Diabetic kidney disease (DKD) is the most common microvascular complication of diabetes and is one of the main causes of end-stage renal disease (ESRD) in many countries. The pathological features of DKD are the hypertrophy of mesangial cells, apoptosis of podocytes, glomerular basement membrane (GBM) thickening, accumulation of extracellular matrix (ECM), glomerular sclerosis, and tubulointerstitial fibrosis. The etiology of DKD is very complicated and many factors are involved, such as genetic factors, hyperglycemia, hypertension, hyperlipidemia, abnormalities of renal hemodynamics, and metabolism of vasoactive substances. Although some achievements have been made in the exploration of the pathogenesis of DKD, the currently available clinical treatment methods are still not completely effective in preventing the progress of DKD to ESRD. CHM composed of natural products has traditionally been used for symptom relief, which may offer new insights into therapeutic development of DKD. We will summarize the progress of Chinese herbal medicine (CHM) in the treatment of DKD from two aspects. In clinical trials, the Chinese herbal formulas were efficacy and safety confirmed by the randomized controlled trials. In terms of experimental research, studies provided evidence for the efficacy of CHM from the perspectives of balancing metabolic disorders, reducing inflammatory response and oxidative stress, antifibrosis, protecting renal innate cells, and regulating microRNA and metabolism. CHM consisting of different ingredients may play a role in synergistic interactions and multiple target points in the treatment of DKD.