Chinese medicine for diabetic kidney disease in China

Advances in Traditional Chinese Medicine research in diabetic kidney disease treatment

CONTEXT

Diabetic kidney disease (DKD) is a prominent complication arising from diabetic microangiopathy, and its prevalence and renal impact have placed it as the primary cause of end-stage renal disease. Traditional Chinese Medicine (TCM) has the distinct advantage of multifaceted and multilevel therapeutic attributes that show efficacy in improving clinical symptoms, reducing proteinuria, protecting renal function, and slowing DKD progression. Over recent decades, extensive research has explored the mechanisms of TCM for preventing and managing DKD, with substantial studies that endorse the therapeutic benefits of TCM compounds and single agents in the medical intervention of DKD.

OBJECTIVE

This review lays the foundation for future evidence-based research efforts and provide a reference point for DKD investigation.

METHODS

The relevant literature published in Chinese and English up to 30 June 2023, was sourced from PubMed, Cochrane Library, VIP Database for Chinese Technical Periodicals (VIP), Wanfang Data, CNKI, and China Biology Medicine disc (CBM). The process involved examining and summarizing research on TCM laboratory tests and clinical randomized controlled trials for DKD treatment.

RESULTS AND CONCLUSIONS

The TCM intervention has shown the potential to inhibit the expression of inflammatory cytokines and various growth factors, lower blood glucose levels, and significantly affect insulin resistance, lipid metabolism, and improved renal function. Furthermore, the efficacy of TCM can be optimized by tailoring personalized treatment regimens based on the unique profiles of individual patients. We anticipate further rigorous and comprehensive clinical and foundational investigations into the mechanisms underlying the role of TCM in treating DKD.

Efficacy of astragalus combined with renin-angiotensin-aldosterone system blockers in the treatment of stage III diabetic nephropathy: a systematic review and meta-analysis

OBJECTIVE

To determine the efficacy and safety of Astragalus combined with renin-angiotensin-aldosterone system (RAAS) blockers in treating stage III diabetic nephropathy (DN) by meta-analysis.

METHODS

PubMed, Embase, Cochrane Library, Wiley, and Web of Science databases were searched for articles published between August 2007 and August 2022. Clinical studies on Astragalus combined with RAAS blockers for the treatment of stage III DN were included. Meta-analysis was performed by RevMan 5.1 and Stata 14.3 software.

RESULTS

A total of 32 papers were included in this meta-analysis, containing 2462 patients from randomized controlled trials, with 1244 receiving the combination treatment and 1218 solely receiving RAAS blockers. Astragalus combined with RAAS blockers yielded a significantly higher total effective rate (TER) (mean difference [MD] 3.63, 95% confidence interval [CI] 2.59-5.09) and significantly reduced urinary protein excretion rate (UPER), serum creatinine (Scr), blood urine nitrogen (BUN) and glycosylated hemoglobin (HbAlc) levels. In subgroup analysis, combining astragalus and angiotensin receptor blocker significantly lowered fasting plasma glucose (FPG) and 24 h urinary protein (24hUTP) levels, compared with the combined astragalus and angiotensin-converting enzyme inhibitor treatment. Meanwhile, the latter significantly decreased the urinary microprotein (β2-MG). Importantly, the sensitivity analysis confirmed the study's stability, and publication bias was not detected for UPER, BUN, HbAlc, FPG, or β2-MG. However, the TER, SCr, and 24hUTP results suggested possible publication bias.

CONCLUSIONS

The astragalus-RAAS blocker combination treatment is safe and improves outcomes; however, rigorous randomized, large-scale, multi-center, double-blind trials are needed to evaluate its efficacy and safety in stage III DN.

Astragaloside IV attenuates high glucose-induced NF-κB-mediated inflammation through activation of PI3K/AKT-ERK-dependent Nrf2/ARE signaling pathway in glomerular mesangial cells

Inflammation is a key contributor to diabetic kidney disease pathogenesis, including reactive oxidation stress (ROS)-mediated nuclear factor-κB (NF-κB) signaling pathway. In this study, we examined the effect of Astragaloside IV (AS-IV) on anti-inflammatory and anti-oxidative properties under high glucose (HG) condition and the potential mechanism in glomerular mesangial cells (GMCs). We showed that AS-IV concentration-dependently reduced GMCs proliferation, restrained ROS release and hydrogen peroxide content, and suppressed pro-inflammatory cytokines as well as pro-fibrotic factors expression, which were associated with the inhibition of NF-κB and nuclear factor-erythroid 2-related factor 2 (Nrf2) signaling activation. Accordingly, both NF-κB overexpression by using RNA plasmid and Nrf2 gene silencing by using RNA interference weakened the ability of AS-IV to ameliorate HG-induced oxidative stress, inflammation, and cell proliferation. Furthermore, phosphatidylinositide 3-kinases (PI3K)/serine/threonine protein kinase (Akt) and extracellular regulated protein kinases (ERK) signaling pathway regulated the process of AS-IV-induced Nrf2 activation and antioxidant capacity, which evidenced by using PI3K inhibitor LY294002 or ERK inhibitor PD98059 that largely abolished the AS-IV efficacy. Taken together, these results indicated that AS-IV protected against HG-induced GMCs damage by inhibiting ROS/NF-kB-induced increases of inflammatory cytokines, fibrosis biomarkers, and cell proliferation via up-regulation of Nrf2-dependent antioxidant enzyme expression, which were mediated by PI3K/Akt and ERK signaling pathway activation.

Evaluation of the efficacy of Abelmoschus manihot (L.) on diabetic nephropathy by analyzing biomarkers in the glomeruli and proximal and distal convoluted tubules of the kidneys

Introduction: As a traditional Chinese medicine, Abelmoschus manihot (L.) in the form of Huangkui (HK) capsule has been used as a medication for kidney diseases, including diabetic nephropathy (DN), in China. The most significant effect of HK capsule treatment in kidney diseases is the reduction of albuminuria and proteinuria. To evaluate the efficacy of HK capsule in the regression of DN, in the current study, we analyzed the biomarkers in the glomerulus and proximal and distal convoluted tubules in the kidneys of db/db mice, the animal model for type 2 diabetes and DN. Methods: Huangkui capsules (0.84 g/kg/d) or vehicle were administered daily via oral gavage for 4 weeks in db/db mice. Urinary albumin-to-creatinine ratio and blood glucose levels were measured during the whole experimental period. Five biomarkers in the glomerulus and proximal and distal convoluted tubules in the kidneys were selected, namely, col4a3, slc5a2, slc34a1, slc12a3, and slc4a1, and their activities at mRNA and protein levels before and after HK capsule treatment were analyzed by real-time RT-PCR and immunohistochemistry. Result and discussion: After HK capsule treatment for 4 weeks, the urinary albumin-to-creatinine ratio in db/db mice was found to be significantly decreased. The activities of col4a3, slc5a2, slc34a1, slc12a3, and slc4a1 in the kidneys were upregulated in db/db mice prior to the treatment but downregulated after HK capsule treatment. Further analyses of the fields of whole kidney tissue sections demonstrated that the number of nephrons in the kidneys of db/db mice with HK capsule treatment was higher than that in the kidneys of db/db mice without HK capsule treatment. Thereby, the current study provides experimental evidence confirming the medical efficacy of A. manihot in the reduction of albuminuria and proteinuria, suggesting that A. manihot may have pharmacological efficacy in the regression of the development of type 2 diabetes-DN.

Traditional Chinese medicine for the treatment of diabetic kidney disease: A study-level pooled analysis of 44 randomized controlled trials

Background: Accumulating evidence suggests that traditional Chinese medicine (TCM) has significant effects on reducing 24-h urinary protein (24-h UPRO) and improves renal function indices. The current level of evidence-based medicine is still not enough due to the limitation of clinical center size and sample size.

Objective: We aimed to update the current evidence on the efficacy of TCM in the treatment of diabetic kidney disease (DKD).

Methods: PubMed, Embase, the Cochrane Library, and SinoMed were searched to identify randomized controlled trials (RCTs) comparing the clinical efficacy of TCM combined with Western medicine with that of Western medicine alone for the treatment of DKD. The main outcome measure was 24-h UPRO. The secondary outcomes were serum creatinine (Scr), blood urea nitrogen (BUN), glycosylated hemoglobin (HbA1c), fasting blood glucose (FBG), total cholesterol (TC), and triglyceride (TG). Meta-analyses were performed using random-effects models. The revised Cochrane risk-of-bias tool was used to assess the risk of bias.

Results: A total of 44 RCTs with 3,730 participants were included. The summary estimates showed that compared with Western medicine alone, TCM combined with Western medicine significantly improved 24-h UPRO [standardized mean difference (SMD) −1.10, 95% confidence interval (CI) −1.45 to −0.74]. Moreover, TCM combined with Western medicine significantly reduced the levels of other renal function indices, including Scr (SMD −1.25, 95% CI: −1.69 to −0.81) and BUN (SMD −0.75, 95% CI: −1.10 to −0.40). TCM combined with Western medicine also showed greater benefits in reducing the levels of FBG (SMD −0.31, 95% CI: −0.47 to −0.15) and HbA1c (SMD −0.62, 95% CI: −0.89 to −0.36) in patients with DKD. In addition, superior effects on the lipid profile were noted in the TCM combined with Western medicine group in terms of TG (SMD −1.17, 95% CI: −1.76 to −0.59) and TC (SMD −0.95, 95% CI: −1.43 to −0.47). The risk of bias could have resulted from selective reports, unclear randomization methods, unblinded assignments, and some missing data.

Conclusion: The results of this meta-analysis suggest that TCM combined with Western medicine has significant effects on reducing 24-h UPRO and improves renal function indices and lipid profiles compared with Western medicine alone for DKD. However, the results should be interpreted with caution due to the risk of bias of the included trials.

Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=213199], identifier [CRD: 42020213199].

A Glimpse of Inflammation and Anti-Inflammation Therapy in Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a common complication of diabetes mellitus and a major cause of end-stage kidney disease (ESKD). The pathogenesis of DKD is very complex and not completely understood. Recently, accumulated evidence from in vitro and in vivo studies has demonstrated that inflammation plays an important role in the pathogenesis and the development of DKD. It has been well known that a variety of pro-inflammatory cytokines and related signaling pathways are involved in the procession of DKD. Additionally, some anti-hyperglycemic agents and mineralocorticoid receptor antagonists (MRAs) that are effective in alleviating the progression of DKD have anti-inflammatory properties, which might have beneficial effects on delaying the progression of DKD. However, there is currently a lack of systematic overviews. In this review, we focus on the novel pro-inflammatory signaling pathways in the development of DKD, including the nuclear factor kappa B (NF-κB) signaling pathway, toll-like receptors (TLRs) and myeloid differentiation primary response 88 (TLRs/MyD88) signaling pathway, adenosine 5′-monophosphate-activated protein kinase (AMPK) signaling pathways, inflammasome activation, mitochondrial DNA (mtDNA) release as well as hypoxia-inducible factor-1(HIF-1) signaling pathway. We also discuss the related anti-inflammation mechanisms of metformin, finerenone, sodium-dependent glucose transporters 2 (SGLT2) inhibitors, Dipeptidyl peptidase-4 (DPP-4) inhibitors, Glucagon-like peptide-1 (GLP-1) receptor agonist and traditional Chinese medicines (TCM).

Promoting Plant-Based Therapies for Chronic Kidney Disease

Chronic kidney disease (CKD) is debilitating, increasing in incidence worldwide, and a financial and social burden on health systems. Kidney failure, the final stage of CKD, is life-threatening if untreated with kidney replacement therapies. Current therapies using commercially-available drugs, such as angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers and calcium channel blockers, generally only delay the progression of CKD. This review article focuses on effective alternative therapies to improve the prevention and treatment of CKD, using plants or plant extracts. Three mechanistic processes that are well-documented in CKD pathogenesis are inflammation, fibrosis, and oxidative stress. Many plants and their extracts are already known to ameliorate kidney dysfunction through antioxidant action, with subsequent benefits on inflammation and fibrosis. In vitro and in vivo experiments using plant-based therapies for pre-clinical research demonstrate some robust therapeutic benefits. In the CKD clinic, combination treatments of plant extracts with conventional therapies that are seen as relatively successful currently may confer additive or synergistic renoprotective effects. Therefore, the aim of recent research is to identify, rigorously test pre-clinically and clinically, and avoid any toxic outcomes to obtain optimal therapeutic benefit from medicinal plants. This review may prove to be a filtering tool to researchers into complementary and alternative medicines to find out the current trends of using plant-based therapies for the treatment of kidney diseases, including CKD.

A comprehensive insight into autophagy and its potential signaling pathways as a therapeutic target in podocyte injury

As part of the glomerular filtration membrane, podocyte is terminally differentiated, structurally unique, and highly specialized in maintaining kidney function. Proteinuria caused by podocyte injury (foot process effacement) is the clinical symptom of various kidney diseases (CKD), including nephrotic syndrome. Podocyte autophagy has become a powerful therapeutic strategy target in ameliorating podocyte injury. Autophagy is known to be associated significantly with sirtuin-1, proteinuria, and podocyte injury. Various key findings in podocyte autophagy were reported in the past ten years, such as the role of endoplasmic reticulum (ER) stress in podocyte autophagy impairment, podocyte autophagy-related gene, essential roles of the signaling pathways: Mammalian Target of Rapamycin (mTOR)/ Phosphoinositide 3-kinase (PI3k)/ serine/threonine kinase 1 (Akt) in podocyte autophagy. These significant factors caused podocyte injury associated with autophagy impairment. Sirtuin-1 was reported to have a vital key role in mTOR signaling, 5'AMP-activated protein kinase (AMPK) regulation, autophagy activation, and various critical pathways associated with podocyte's function and health; it has potential value to podocyte injury pathogenesis investigation. From these findings, podocyte autophagy has become an attractive therapeutic strategy to ameliorate podocyte injury, and this review will provide an in-depth review on therapeutic targets he podocyte autophagy.

Buyang Huanwu Decoction protects against STZ-induced diabetic nephropathy by inhibiting TGF-β/Smad3 signaling-mediated renal fibrosis and inflammation

Background

Buyang Huanwu Decoction (BHD) is a classical Chinese Medicine formula empirically used for diabetic nephropathy (DN). However, its therapeutic efficacies and the underlying mechanisms remain obscure. In our study, we aim to evaluate the renoprotective effect of BHD on a streptozotocin (STZ)-induced diabetic nephropathy mouse model and explore the potential underlying mechanism in mouse mesangial cells (MCs) treated with high glucose in vitro, followed by screening the active compounds in BHD.

Methods

Mice were received 50 mg/kg streptozotocin (STZ) or citrate buffer intraperitoneally for 5 consecutive days. BHD was intragastrically administrated for 12 weeks starting from week 4 after the diabetes induction. The quality control and quantitative analysis of BHD were studied by high-performance liquid chromatography (HPLC). Renal function was evaluated by urinary albumin excretion (UAE) using ELISA. The mesangial matrix expansion and renal fibrosis were measured using periodic acid-schiff (PAS) staining and Masson Trichrome staining. Mouse mesangial cells (MCs) were employed to study molecular mechanisms.

Results

We found that the impaired renal function in diabetic nephropathy was significantly restored by BHD, as indicated by the decreased UAE without affecting the blood glucose level. Consistently, BHD markedly alleviated STZ-induced diabetic glomerulosclerosis and tubulointerstitial injury as shown by PAS staining, accompanied by a reduction of renal inflammation and fibrosis. Mechanistically, BHD inhibited the activation of TGF-β1/Smad3 and NF-κB signaling in diabetic nephropathy while suppressing Arkadia expression and restoring renal Smad7. We further found that calycosin-7-glucoside (CG) was one of the active compounds from BHD, which significantly suppressed high glucose-induced inflammation and fibrosis by inhibiting TGF-β1/Smad3 and NF-κB signaling pathways in mesangial cells.

Conclusion

BHD could attenuate renal fibrosis and inflammation in STZ-induced diabetic kidneys via inhibiting TGF-β1/Smad3 and NF-κB signaling while suppressing the Arkadia and restoring renal Smad7. CG could be one of the active compounds in BHD to suppress renal inflammation and fibrosis in diabetic nephropathy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-021-00531-1.

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.

Astragaloside IV protects against podocyte apoptosis by inhibiting oxidative stress via activating PPARγ-Klotho-FoxO1 axis in diabetic nephropathy

AIMS

Podocyte apoptosis plays an important role in the pathogenesis of diabetic nephropathy (DN). Astragaloside IV (AS-IV) has been shown to protect against podocyte apoptosis. Here we aim to investigate the mechanism responsible for the protective effects of AS-IV.

MAIN METHODS

Diabetic db/db mice and high glucose (HG)-cultured podocytes were treated with AS-IV. Renal function and histopathological changes were measured to evaluate the therapeutic effects of AS-IV against DN. Adenovirus-mediated Klotho overexpression, Klotho siRNA, and PPARγ inhibitor were applied in vitro to investigate the potential mechanism. The expression levels of mRNA and proteins were analyzed by qRT-PCR, western blot or immunofluorescence. Intracellular ROS and mitochondrial superoxide were detected by DHE and MitoSOx Red, respectively. Cell apoptosis was evaluated by TUNEL staining and flow cytometry.

KEY FINDINGS

AS-IV improved renal function and ameliorated podocyte injury in db/db mice accompanied with enhanced Klotho expression in glomerular podocytes. In vitro, AS-IV inhibited HG-induced podocyte apoptosis and restored HG-inhibited Klotho expression, whereas Klotho knockdown abrogated the anti-apoptosis action of AS-IV. Further study showed that adenovirus-mediated Klotho overexpression enhanced Forkhead transcription factor O1 (FoxO1)-dependent antioxidant activity and attenuated HG-evoked oxidative stress and apoptosis. AS-IV prevented HG-induced FoxO1 inhibition and oxidative stress, whereas Klotho knockdown reversed these effects. Cotreatment with PPARγ inhibitor T0070907 abolished AS-IV-induced Klotho expression and anti-apoptosis action.

SIGNIFICANCE

These data suggested that AS-IV attenuated podocyte apoptosis presumably by inhibiting oxidative stress via activating PPARγ-Klotho-FoxO1 signaling pathway, thereby ameliorating DN. This study provided new insights into the molecular mechanisms of AS-IV against DN.

Amygdalin alleviates renal injury by suppressing inflammation, oxidative stress and fibrosis in streptozotocin-induced diabetic rats

AIMS

To explore the protective efficacies and potent mechanism of amygdalin on high glucose-cultured renal cell HBZY-1 in vitro and streptozotocin (STZ)-induced diabetic nephropathy (DN) rat in vivo.

MAIN METHODS

The cellar proliferation and generation of ROS in high-glucose cultured HBZY-1 cell were assessed by MTT and DCFH-DA assay, respectively. The fasting blood glucose levels, renal function and inflammation indexes as well as oxidative stress markers in STZ-induced diabetic rats were all measured. The histologic renal section was stained with Mason and periodic acid-Schiff (PAS) method. Immunohistochemistry and western blotting methods were applied to assess expression levels of extracellular matrix (ECM), epithelial-mesenchymal transition (EMT)-related as well as TGF-β1/Smad signaling pathway-related proteins.

KEY FINDINGS

Firstly, amygdalin significantly suppressed the excessive cell proliferation and ROS generation in HBZY-1 cells cultured with high glucose. The hyperglycemia, 24 h-UP excretion, BUN and Scr of DN rats were significantly attenuated after the chronic treatment of amygdalin. Moreover, MDA, SOD, IFN-γ and IL-12 levels in kidney tissues were all effectively reduced. Besides, amygdalin can suppress the ECM accumulation and EMT transformation by inhibiting Smad/TGF-β pathway to alleviate the renal fibrosis in renal tissues of DN model rats.

SIGNIFICANCE

Amygdalin ameliorates excessive oxidative stress, inflammation and renal tissue fibrosis of DN mainly by suppressing TGF-β1/Smad signaling pathway and regulating the key enzymes of ECM degradation.

Danhong injection for the treatment of early diabetic nephropathy: A protocol of systematic review and meta-analysis

BACKGROUND

Diabetic nephropathy (DN) is the one that of the most common complications of diabetes mellitus (DM). Diabetic patients will experience a high mortality rate when DN progress to end-stage. So, it is extremely important to early treat DN. Although several interventions have been used to treat DN, a conclusive finding has not already been achieved. As one of the most common Chinese medicines, danhong injection (DHI) which has been shown to have various functions has also been prescribed to be as the alternative treatment option. However, no systematic review and meta-analysis has been conducted to objectively and comprehensively investigate its effectiveness and safety. Thus, we designed the current systematic review and meta-analysis to answer whether DHI can be preferably used to timely treat DN.

METHODS

We will perform a systematic search to capture any potentially eligible studies in several electronic databases including PubMed, Cochrane library, Embase, China National Knowledgement Infrastructure (CNKI), Wanfang database, and Chinese sci-tech periodical full-text database (VIP) from their inception to August 31, 2020. We will assign 2 independent reviewers to select eligible studies, and assess the quality of included studies with Cochrane risk of bias assessment tool. We will perform all statistical analyses using RevMan 5.3 software.

ETHICS AND DISSEMINATION

We will submit our findings to be taken into consideration for publication in a peer-reviewed academic journal. Meanwhile, we will also communicate our findings in important conferences.

PROTOCOL REGISTRY

The protocol of this systematic review and meta-analysis has been registered at the International Plateform of Registered Systematic Review and Meta-Analysis Protocols (INPLASY) platform (https://inplasy.com/inplasy-2020-9-0005/, registry number: INPLASY202090005) and this protocol was funded through a protocol registry.

Clinical efficacy and safety of Chinese herbal medicine for the treatment of patients with early diabetic nephropathy: A protocol for systematic review and meta-analysis

BACKGROUND

Diabetic nephropathy (DN) is among the common and serious complications of diabetes and is also a major cause of end-stage kidney disease. Early DN is also called diabetic microalbumin period, the main treatment is in the control of blood sugar on the basis of kidney protection and urine lowering protein. There are few effective methods of western medicine treatment, and most of them are accompanied by adverse reactions. But some studies have shown that traditional Chinese medicine has achieved the curative effect and has certain superiority. However, there are few systematic reviews on the treatment of traditional Chinese herbal medicine for early DN currently. Therefore, this study conducted a systematic review of clinical efficacy and safety of Chinese herbal medicine for the treatment of patients with early DN, aim to comprehensively analyze the role of traditional Chinese herbal medicine in the treatment of early DN.

METHODS AND ANALYSIS

The protocol of this systematic review and meta-analysis was registered on the INPLASY website (https://inplasy.com/inplasy-2020-4-0139/) and INPLASY registration number is INPLASY202040139. A systematic literature search will be conducted in 3 English database and 4 Chinese databases with a language limitation of English and Chinese. Search for clinical research literature on Chinese herbal medicine treatment of DN published in domestic and foreign biomedical journals. The time is limited from January 2010 to February 2020. We will investigate heterogeneity across studies and publication bias. To assess the risk of bias and quality of the included studies, we will use the Cochrane Collaboration's ROB tool. According to the relevant standards in the Cochrane Intervention System Evaluation Manual, it will be divided into low risk, high risk, and unclear. We will also use the RevMan 5.3 software and Stata 13.0 software for meta-analysis of the effectiveness and symptom scores of DN proteinuria.

ETHICS AND DISSEMINATION

The ethical considerations are not required because the systematic review is based on published studies. The systematic review and meta-analysis will be published in a peer-reviewed Journal.

Shenkang Injection protects against diabetic nephropathy in streptozotocin (STZ)-induced mice through enhancement of anti-oxidant and anti-inflammatory activities

Objective

To investigate the protective effects and possible mechanisms of Shenkang Injection (SKI) on the diabetic nephropathy in streptozotocin-induced mice.

Methods

STZ with the feeding of high fat diet (HFD) was used to induce diabetic mice. The balb/c mice and diabetic mice were then randomly divided into five groups: (1) control group, (2) model group, (3) alprostadil (Alp, 1.5 μg/kg) group, (4) SKI (30 ml/kg) group, (5) Alp (1.5 μg/kg) + SKI (15 ml/kg) group. After six weeks' treatment, blood, urine and kidney tissues were collected for biochemical assay, ELISA assay, and pathological analysis.

Results

Diabetic mice exhibited evident manifestations of diabetic nephropathy (DN), as indicated by increased 24-h urine volume, urinary albumin and kidney weight index (P < 0.01), which could be attenuated by SKI treatment (P < 0.01). SKI was further found to improve abnormal morphology in glomerulus with increased glomerular volume and to decrease urinary N-acetyl-b-D-glucpsaminidase (NAG), β2-microglobulin (β2-MG), and kidney injury molecules-1 (KIM-1) levels (P < 0.05, P < 0.01). Plasma levels of anti-oxidant enzymes significantly reduced in the diabetic mice, and those decreases could be reversed by SKI and Alp treatments. Additionally, SKI obviously suppressed the diabetes-induced increases of pro-inflammatory cytokines (IL-6, IL-1β and TNF-α) (P < 0.01). Meanwhile, SKI was found to effectively attenuate the diabetes-induced coagulation dysfunction, as evidenced by lengthening prothrombin and thrombin time, and decreasing plasma levels of fibrinogen (FIB), 6-K-PGF1α and thromboxane B2 (TXB2) (P < 0.05, P < 0.01). With SKI and Alp combined treatment, the anti-oxidant activities and improvements of coagulation dysfunction were enhanced.

Conclusion

SKI possesses a remarkable property to prevent diabetic nephropathy. The improvements of kidney function and hypercoagulability by SKI were enhanced with Alp combined treatment. The molecular mechanisms underlying the protection of SKI against DN may be related to enhancing the anti-oxidant and anti-inflammatory activities, and improving the coagulation dysfunction.

ErHuang Formula Improves Renal Fibrosis in Diabetic Nephropathy Rats by Inhibiting CXCL6/JAK/STAT3 Signaling Pathway

Diabetic nephropathy (DN) is one of the main causes of renal fibrosis and is associated with high morbidity and mortality. Traditional Chinese Medicine (TCM) therapy has a long history of usage in a clinical setting and its usage is increasing. ErHuang Formula (EHF), a Chinese herbal compound, has been clinically used in treating DN for more than 30 years. However, its mechanism of action is still unknown. This study was conducted to evaluate the effect of EHF on renal fibrosis in a DN rat model and explore its underlying mechanism. The DN rat model was established by high-sugar-fat diet combined with a single intraperitoneal injection of streptozotocin (STZ), and EFH extract (4, 2, 1 g/kg d⁻¹) was administered orally for 8 weeks. The biochemical parameters (blood glucose, weight, Scr, BUN, UA, U-Alb and UAE) were analyzed. The pathological changes in renal tissue were observed by histological staining with H&E and Masson. The effect of EHF on the proliferation of NRK-49F cells was examined by CCK-8 assay and the levels of several inflammation and fibrosis related cytokines (IL-6, TNF-α, TGF-β1, Collagen I/III, MMP2/9) in serum and NRK-49F cell culture supernatants were detected by enzyme-linked immunoassay (ELISA). The mRNA levels of CXCL6, CXCR1, Collagen I/III, MMP2/9 in renal tissue were also measured by quantitative RT-PCR. Furthermore, the protein expression of PCNA, Collagen I/III, MMP2/9, CXCL6, CXCR1, p-STAT3, STAT3 in renal tissue and NRK-49F cells were determined by western blot. EHF improved the abnormal biochemical parameters and ameliorated the abnormal histology and fibrosis of renal tissue in a dose-dependent manner. EHF inhibited NRK-49F proliferation and decreased the expressions of inflammation and fibrosis related factors both in vitro and in vivo. Interestingly, the levels of Collagen I/III, PCNA, MMP2/9 and p-STAT3 were positively correlated with CXCL6. The amelioration of renal fibrosis in DN by EHF is related to CXCL6/JAK/STAT3 signal pathway, which is associated with inflammation and fibrosis of the tissue. These findings may have clinical implications for the treatment of DN.

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.