Astragalus polysaccharides protect renal function and affect the TGF-/Smad signaling pathway in streptozotocin-induced diabetic rats

Chemical Composition and Therapeutic Effects of Several Astragalus Species (Fabaceae)

The review integrates information on the component composition and biological activity of some Astragalus L. (Fabaceae) species from studies reported over the past 5-7 years. The aerial and underground parts of 34 Astragalus species contain triterpene saponins, flavonoids, polysacharides, tannins, free organic acids, higher fatty acids, vitamins, trace elements, and other constituents. Among the Astragalus species, A. membranaceus (Fisch.) Bunge is the best studied in terms of component composition and biological activity. Anti-inflammatory, immunomodulatory, antioxidant, anticancer, cardioprotective, and hepathoprotective activities have been experimentally detected in total bioactive substances, fractions, and individual compounds extracted from various parts of A. membranaceus and A. membranaceus var. mongholicus in vitro and in vivo. The composition and biological effects of other Astragalus species are still poorly understood. The review summarizes the recent advances in studying new compounds extracted from Astragalus species and their biological activities.

Astragalus polysaccharide attenuates diabetic nephropathy by reducing apoptosis and enhancing autophagy through activation of Sirt1/FoxO1 pathway

OBJECTIVE

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease in diabetic patients. Astragalus polysaccharide (APS) is a natural active ingredient in Astragalus membranaceus with anti-hypertensive and anti-oxidative properties. This study aimed to explore the protective roles of APS and its underlying mechanisms in DN.

METHODS

After the establishment of a rat model of DN by a high-fat diet and treatment with 30 mg/kg streptozotocin (STZ), the effects of 100 mg/kg APS on the levels of serum creatinine, blood urea nitrogen, blood glucose, and urinary albumin-to-creatinine ratio were measured. Histopathological alterations in renal tissues, renal cell apoptosis, renal inflammation, and oxidative stress were examined. The impacts of 0-200 μg/mL APS on the viability and apoptosis in high glucose (HG)-stimulated podocytes were measured by Cell Counting Kit-8 assays and flow cytometry, respectively. The expression of genes was tested by immunoblotting, quantitative real-time PCR, and immunofluorescence staining.

RESULTS

APS enhanced the expression of podocin and nephrin, increased viability, and reduced apoptosis in HG-induced podocytes. APS treatment abrogated high glucose-mediate suppression of autophagy in podocytes by activating the Sirt1/FoxO1 pathway. The Sirt1 inhibitor EX-527 eliminated the ameliorative effects of APS on renal dysfunction and renal tissue damage, as well as the inhibitory effects of APS on oxidative stress, inflammation, and apoptosis in DN rats. Moreover, EX-527 inhibited APS-induced autophagy activation in DN rats.

CONCLUSION

APS mitigated DN under hyperglycemic conditions by activating the Sirt1/FoxO1 autophagy pathway, suggesting that APS is a promising agent for DN treatment.

Astragalus membranaceus: A Review of Its Antitumor Effects on Non-Small Cell Lung Cancer

The rising global morbidity and mortality rates of non-small cell lung cancer (NSCLC) underscore the urgent need for more effective treatments. Current therapeutic modalities-including surgery, radiotherapy, chemotherapy, and targeted therapy-face several limitations. Recently, Astragalus membranaceus, a traditional Chinese medicine (TCM), has captured significant attention due to its broad pharmacological properties, such as immune regulation, anti-inflammatory effects, and the modulation of reactive oxygen species (ROS) and enzyme activities. This review delivers a comprehensive summary of the most recent advancements and ongoing applications of Astragalus membranaceus in NSCLC treatment, underlining its potential for integration into existing treatment protocols. It also highlights essential areas for future research, including the elucidation of its molecular mechanisms, optimization of dosage and administration, and evaluation of its efficacy and safety alongside standard therapies, all of which could potentially improve therapeutic outcomes for NSCLC patients.

Investigating the protective effects of Astragalus polysaccharides on cyclophosphamide-induced bone marrow suppression in mice and bone mesenchymal stem cells

BACKGROUND

This study determines the role and mechanism of APS in cyclophosphamide-induced myelosuppression in mice and bone mesenchymal stem cells (BMSCs) cell model.

METHODS

Cy-induced myelosuppression mice and BMSCs cell model were established. Fifty C57BL/6 mice (weighing 20 ± 2 g) were randomly divided into five groups. Femur and tibia samples, bone marrow samples, and blood samples were collected 3 days after the last injection of Cy. Histopathology changes and cell apoptosis were detected. Cell viability, apoptosis, cycle distribution, reactive oxygen species activity, osteogenesis ability, and protein levels were detected. γ-H2AX and senescence-associated β-galactosidase activity expression was detected by immunofluorescence. Cy-induced senescence and Wnt/β-catenin related protein levels were detected using western blotting.

RESULTS

The results showed that APS effectively induced Cy-induced histological injury and cell apoptosis rate. After treated with APS, ROS and ALP levels were significantly increased. In BMSCs, cell viability, apoptosis, and cell cycle distribution were also influenced by APS treatment. Compared with the control group, cell viability was significantly increased, the cell apoptosis rate was decreased while the number of cells remained in the G0-G1 phase was increased. Meanwhile, ROS levels were significantly increased in APS group. Cell senescence and Wnt/β-catenin related protein (γ-H2AX, SA-β-gal, p21, p16, p-β-catenin/ β-catenin, c-Myc, and AXIN2) levels were also altered both in vivo and in vitro. Interestingly, the effects of APS were reversed by BML-284.

CONCLUSION

Our results indicate that APS protected Cy-induced myelosuppression through the Wnt/β-catenin pathway and APS is a potential therapeutic drug for Cy-induced myelosuppression.

The potential of astragalus polysaccharide for treating diabetes and its action mechanism

Type 2 diabetes presents a significant global health burden and is frequently linked to serious clinical complications, including diabetic cardiomyopathy, nephropathy, and retinopathy. Astragalus polysaccharide (APS), extracted from Astragalus membranaceus, exhibits various biochemical and physiological effects. In recent years, a growing number of researchers have investigated the role of APS in glucose control and the treatment of diabetes and its complications in various diabetes models, positioning APS as a promising candidate for diabetes therapy. This review surveys the literature on APS from several databases over the past 20 years, detailing its mechanisms of action in preventing and treating diabetes mellitus. The findings indicate that APS can address diabetes by enhancing insulin resistance, modulating the immune system, protecting islet cells, and improving the intestinal microbiota. APS demonstrates positive pharmacological value and clinical potential in managing diabetic complications, including diabetic retinopathy, nephropathy, cardiomyopathy, cognitive dysfunction, wound healing, and more. However, further research is necessary to explore APS's bioavailability, optimal dosage, and additional clinical evidence.

Herb pair of Rhubarb-Astragalus mitigates renal interstitial fibrosis through downregulation of autophagy via p38-MAPK/TGF-β1 and p38-MAPK/smad2/3 pathways

BACKGROUND

Chronic kidney disease (CKD) has a high incidence and poor prognosis; however, no effective treatment is currently available. Our previous study found that the improvement effect of the herb pair of Rhubarb-Astragalus on CKD is likely related to the inhibition of the TGF-β1/p38-MAPK pathway. In the present study, a p38-MAPK inhibitor was used to further investigate the inhibitory effect of Rhubarb-Astragalus on the TGF-β1/p38-MAPK pathway and its relationship with autophagy.

METHODS

A rat model of unilateral ureteral obstruction (UUO) was established, and a subgroup of rats was administered Rhubarb-Astragalus. Renal function and renal interstitial fibrosis (RIF) were assessed 21 d after UUO induction. In vitro, HK-2 cells were treated with TGF-β1 and a subset of cells were treated with Rhubarb-Astragalus or p38-MAPK inhibitor. Western blotting, immunohistochemistry, and qRT-PCR analyses were used to detect the relevant protein and mRNA levels. Transmission electron microscopy was used to observe autophagosomes.

RESULTS

Rhubarb-Astragalus treatment markedly decreased the elevated levels of blood urea nitrogen, serum creatinine, and urinary N-acetyl-β-D-glucosaminidase; attenuated renal damage and RIF induced by UUO; and reduced the number of autophagosomes and lysosomes in UUO-induced renal tissues. Additionally, Rhubarb-Astragalus reduced the protein and mRNA levels of α-SMA, collagen I, LC3, Atg3, TGF-β1, p38-MAPK, smad2/3, and TAK1 in renal tissues of UUO rats. Rhubarb-Astragalus also reduced protein and mRNA levels of these indicators in vitro. Importantly, the effect of the p38-MAPK inhibitor was similar to that of Rhubarb-Astragalus.

CONCLUSIONS

Rhubarb-Astragalus improves CKD possibly by downregulating autophagy via the p38-MAPK/TGF-β1 and p38-MAPK/smad2/3 pathways.

Pharmacological potential of Astragali Radix for the treatment of kidney diseases

BACKGROUND

With the increasing prevalence of hypertension, diabetes, and obesity, the incidence of kidney diseases is also increasing, resulting in a serious public burden. Conventional treatments for kidney diseases have unsatisfactory effects and are associated with adverse reactions. Traditional Chinese medicines have good curative effects and advantages over conventional treatments for preventing and treating kidney diseases. Astragali Radix is a Chinese herbal medicine widely used to treat kidney diseases.

PURPOSE

To review the potential applications and molecular mechanisms underlying the renal protective effects of Astragali Radix and its components and to provide direction and reference for new therapeutic strategies and future research and development of Astragali Radix.

STUDY DESIGN AND METHODS

PubMed, Google Scholar, and Web of Science were searched using keywords, including "Astragali Radix," "Astragalus," "Astragaloside IV" (AS-IV), "Astragali Radix polysaccharide" (APS), and "kidney diseases." Reports on the effects of Astragali Radix and its components on kidney diseases were identified and reviewed.

RESULTS

The main components of Astragali Radix with kidney-protective properties include AS-IV, APS, calycosin, formononetin, and hederagenin. Astragali Radix and its active components have potential pharmacological effects for the treatment of kidney diseases, including acute kidney injury, diabetic nephropathy, hypertensive renal damage, chronic glomerulonephritis, and kidney stones. The pharmacological effects of Astragali Radix are manifested through the inhibition of inflammation, oxidative stress, fibrosis, endoplasmic reticulum stress, apoptosis, and ferroptosis, as well as the regulation of autophagy.

CONCLUSION

Astragali Radix is a promising drug candidate for treating kidney diseases. However, current research is limited to animal and cell studies, underscoring the need for further verifications using high-quality clinical data.

Antioxidant therapy against TGF-β/SMAD pathway involved in organ fibrosis

Fibrosis refers to excessive build-up of scar tissue and extracellular matrix components in different organs. In recent years, it has been revealed that different cytokines and chemokines, especially Transforming growth factor beta (TGF-β) is involved in the pathogenesis of fibrosis. It has been shown that TGF-β is upregulated in fibrotic tissues, and contributes to fibrosis by mediating pathways that are related to matrix preservation and fibroblasts differentiation. There is no doubt that antioxidants protect against different inflammatory conditions by reversing the effects of nitrogen, oxygen and sulfur-based reactive elements. Oxidative stress has a direct impact on chronic inflammation, and as results, prolonged inflammation ultimately results in fibrosis. Different types of antioxidants, in the forms of vitamins, natural compounds or synthetic ones, have been proven to be beneficial in the protection against fibrotic conditions both in vitro and in vivo. In this study, we reviewed the role of different compounds with antioxidant activity in induction or inhibition of TGF-β/SMAD signalling pathway, with regard to different fibrotic conditions such as gastro-intestinal fibrosis, cardiac fibrosis, pulmonary fibrosis, skin fibrosis, renal fibrosis and also some rare cases of fibrosis, both in animal models and cell lines.

Astragalus polysaccharide promotes autophagy and alleviates diabetic nephropathy by targeting the lncRNA Gm41268/PRLR pathway

BACKGROUND

Astragalus polysaccharide (APS) is a major bioactive component of the Chinese herb astragalus, with well-established protective effects on the kidney. However, the effect of APS on diabetic nephropathy (DN) is unclear.

METHODS

Long non-coding RNA (lncRNA) expression profiles in kidney samples from control, db/db, and APS-treated db/db mice were evaluated using RNA high-throughput sequencing techniques. Additionally, rat renal tubular epithelial (NRK-52E) cells were cultured in high glucose (HG) media. We inhibited the expression of Gm41268 and prolactin receptor (PRLR) by transfecting NRK-52E cells with Gm41268-targeting antisense oligonucleotides and PRLR siRNA.

RESULTS

We found that APS treatment reduced 24-h urinary protein levels and fasting blood glucose and improved glucose intolerance and pathological renal damage in db/db mice. Furthermore, APS treatment enhanced autophagy and alleviated fibrosis in the db/db mice. We identified a novel lncRNA, Gm41268, which was differentially expressed in the three groups, and the cis-regulatory target gene PRLR. APS treatment induced autophagy by reducing p62 and p-mammalian target of rapamycin (mTOR) protein levels and increasing the LC3 II/I ratio. Furthermore, APS alleviated fibrosis by downregulating fibronectin (FN), transforming growth factor-β (TGF-β), and collagen IV levels. In addition, APS reversed the HG-induced overexpression of Gm41268 and PRLR. Reduction of Gm41268 decreased PRLR expression, restored autophagy, and ameliorated renal fibrosis in vitro. Inhibition of PRLR could enhance the protective effect of APS.

CONCLUSIONS

In summary, we demonstrated that the therapeutic effect of APS on DN is mediated via the Gm41268/PRLR pathway. This information contributes to the exploration of bioactive constituents in Chinese herbs as potential treatments for DN.

Hedysarum polybotrys polysaccharide attenuates renal inflammatory infiltration and fibrosis in diabetic mice by inhibiting the HMGB1/RAGE/TLR4 pathway

Diabetic kidney disease (DKD) is a leading cause of kidney failure. Previous studies demonstrated the therapeutic potential of Astragalus polysaccharide in treating diabetic nephropathy. Astragalus and Hongqi both come from the leguminous plant Astragalus, but their species and genera are different, belonging to the same family and different genera of traditional Chinese medicinal plants. However, the effects of Hedysarum polybotrys polysaccharide (HPS), a polysaccharide compound from Hongqi, on DKD, including its components and efficacy, have remained elusive. The present study utilized db/db mice as a DKD animal model administered with low (30 mg/kg) and high doses (60 mg/kg) of HPS, in addition to glyburide (7.2 mg/kg). Blood and urine samples were collected from mice and blood glucose, serum creatinine, urinary albumin excretion and urinary β2-microglobulin were measured. In addition, apoptosis and histological changes in kidney tissue were observed using TUNEL and HE staining, respectively, and the secretion and expression of inflammatory factors in kidney tissue were detected using EILSA and reverse transcription-quantitative PCR. Furthermore, we the expression of fibrosis-related proteins and NF-κB signaling pathway proteins was determined using western blot analysis. HPS was found to reduce the blood glucose concentration, serum creatinine levels, urinary albumin excretion rates and urinary β2-microglobulin in a dose-dependent manner. In addition, HPS treatment mitigated apoptosis and pathological damage in the kidney tissues of DKD mice. The expression levels of fibrosis-related proteins fibronectin, α-smooth muscle actin and TGF-β1 were observed to be decreased in kidney tissues of DKD mice following HPS treatment. The secretion levels of inflammatory factors (IL-6, TNF-α and IL-1β) were also reduced in kidney tissues, with high-dose HPS treatment found to be more effective, similar to the effects mediated by the glyburide. Further mechanistic analysis revealed that the therapeutic effects of HPS on DKD mice may be mediated by inhibiting the high mobility group box 1/receptor for advanced glycation end-products/toll-like receptor 4 pathway. In conclusion, the present findings could provide insight for the treatment of DKD.

Astragalus Polysaccharide Ameliorates Renal Inflammatory Responses in a Diabetic Nephropathy by Suppressing the TLR4/NF-κB Pathway

Background

Diabetic nephropathy (DN), as a chronic inflammatory complication of diabetes, is characterized by hyperglycemia, albuminuria and edema, which ultimately becomes the leading cause of end-stage renal disease (ESRD). Astragalus polysaccharide (APS), extracted from the Astragalus membranaceus, was widely used in the treatment of diabetes mellitus. However, the functional roles of APS ameliorate inflammatory responses in DN, which remain poorly understood. Therefore, the purpose of this study was to explore the molecular mechanism of APS on DN in vivo and vitro models.

Methods

We explored the beneficial effects of APS in streptozotocin (STZ)-induced DN rat model and high glucose (HG)-treated glomerular podocyte model. The fasting blood glucose (FBG) and ratio of kidney weight to body weight were measured after 4 weeks of APS treatment. The renal injury parameters containing serum creatinine (Scr), blood urea nitrogen (BUN) and 24 h urinary protein were evaluated. The renal pathological examination was observed by hematoxylin-eosin (HE) staining. The levels of IL-1β, IL-6 and MCP-1 were evaluated by ELISA assay. The proliferation of podocytes was determined using CCK-8 assay and flow cytometry. qRT-PCR and Western blot analysis were performed to determine the amounts of TLR4/NF-κB-related gene expression.

Results

Our results indicated that APS effectively decreased the levels of FBG, BUN, Scr and renal pathological damage when compared with STZ-induced DN model group. Additionally, APS significantly ameliorated renal injury by reducing inflammatory cytokines IL-1β, IL-6, MCP-1 expression and inhibiting the TLR4/NF-κB pathway activity in DN rats. Consistent with the results in vitro, the HG-induced inflammatory response and proliferation of glomerular podocytes were also alleviated through APS administration.

Conclusion

We found that APS ameliorated DN renal injury, and the mechanisms perhaps related to relieving inflammatory responses and attenuating the TLR4/NF-κB signaling pathway.

Astragalus polysaccharide alleviates alcoholic-induced hepatic fibrosis by inhibiting polymerase I and transcript release factor and the TLR4/JNK/NF-κB/MyD88 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Astragali Radix (AR), the root of Astragalus membranaceus (Fisch.) Bge. or Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao, known as Huangqi in traditional Chinese medicine, has been widely used in traditional Chinese medicine prescriptions for acute and chronic liver injury. AR was the most important medicine in a Chinese traditional prescription called Huangqi Decoction (HQD), has been used to treat chronic liver diseases since the 11th century. In particular, its major active ingredient, Astragalus polysaccharide (APS), has demonstrated promising effects on inhibiting hepatic fibrosis. However, to date, the effect of APS against alcohol-induced hepatic fibrosis and its underlying molecular mechanisms remains unknown.

AIMS OF THE STUDY

This study aimed to explore the effect and potential molecular mechanisms of APS against alcohol-induced hepatic fibrosis by using network pharmacology and experimental validation.

MATERIALS AND METHODS

The potential targets and underling mechanism of AR in alcoholic liver fibrosis was first predicted using network pharmacology, followed by experimental validation using SD rat model with alcohol-induced hepatic fibrosis. Further, the predicted candidate signaling pathways and potential target polymerase I and transcript release factor (PTRF) were combined to explore the multifaceted mechanism of APS against alcohol-induced hepatic fibrosis. Finally, overexpression of PTRF was explored to reveal the role of PTRF in the mechanism of APS against alcohol-induced hepatic fibrosis.

RESULT

APS exerted potent anti-hepatic fibrosis effects by downregulating genes involved in the Toll-like receptor 4 (TLR4)/JNK/NF-κB/MyD88 pathway. Notably, APS treatment ameliorated the hepatic damage by inhibiting the overexpression of PTRF and decreasing the co-localisation of TLR4/PTRF. Overexpression of PTRF induced reversal of the protective effects of APS on alcohol-induced hepatic fibrosis.

CONCLUSION

This study indicated that APS may alleviate alcohol-induced hepatic fibrosis by inhibiting the activation of PTRF/TLR4/JNK/NF-κB/MyD88 pathway, which provides a scientific elucidation for the mechanisms of APS on the anti-hepatic fibrosis activity and presents a promising therapeutic approach for treating hepatic fibrosis.

Extraction, structure, and activity of polysaccharide from Radix astragali

Radix astragali polysaccharide (RAP) is a water-soluble heteropolysaccharide. It is an immune promoter and regulator, and has antivirus, antitumor, anti-aging, anti-radiation, anti-stress, anti-oxidation and other activitys. The extraction, separation, purification, structure, activity and modification of RAP were summarized. Some extraction methods of RAP had been introduced, and the separation and purification methods of RAP were reviewed, and the structure and activity of RAP were highly discussed. Current derivatization of RAP was outlined. Through the above discussion that the yield of crude polysaccharides from Radix astragali by enzyme-assisted extraction was significantly higher than that by other extraction methods, but each extraction method had different extraction effects under certain conditions, and the activity efficiency of RAP was also different. Therefore, it is particularly important to optimize the extraction method with known better yield for the study of RAP. In addition, the purification and separation of RAP are the key factors affecting the yield and activity of RAP. At the same time, there are still few studies on the derivatiration of Radix astragali polysaccharide, but the researches in this area are very important. RAP also has many important pharmacological effects on human body, but its practical application needs further study. Finally, studies on the structure-activity relationship of RAP still need to be carried out by many scholars. This review would provide some help for further researches on various important applications of RAP.

Astragalus Polysaccharide Relieves Inflammatory Responses in Guinea Pigs with Allergic Rhinitis via Ameliorating NF-kB-Mediated Treg/Th17 Imbalance

BACKGROUND

Allergic rhinitis (AR) is regarded as a prevalent and non-infectious inflammation in nasal mucosa, and astragalus polysaccharide (APS) could mitigate inflammation.

OBJECTIVES

Herein, this study probed the specific mechanism of APS in inflammatory responses in AR.

METHODS

Firstly, AR guinea pig models were established through the stimulation and sensitization of ovalbumin (OVA) and received APS treatment. Changes in nasal symptoms were assessed through counting the sneezing and rubbing times of guinea pigs. The change patterns of OVA-specific immunoglobulin-E (OVA-sIgE), OVA-specific immunoglobulin-G1 (OVA-sIgG1), tumor necrosis factor (TNF)-α, and interleukin (IL)-6 in guinea pig serum were identified. Meanwhile, the levels of IL-17, transforming growth factor (TGF)-β, IL-10, and forkhead box protein P3 (Foxp3) in the guinea pig tissues or serum were examined, and CD25⁺Foxp3⁺Treg or CD4⁺IL17⁺Th17 cell proportion was detected. Afterwards, nuclear factor-kappa B (NF-kB) expression in guinea pig nasal mucosa tissues were examined. Rescue experiments were designed to probe the role of NF-kB overexpression in inflammatory responses and Treg/Th17 imbalance in AR guinea pigs.

RESULTS

APS treatment reduced sneezing and rubbing times of AR guinea pigs and suppressed OVA-sIgE, OVA-sIgG1, TNF-α, and IL-6 levels in guinea pig serum, and meanwhile, increased CD25⁺Foxp3⁺Treg cell proportion while reduced CD4⁺IL17⁺Th17 cell proportion in AR guinea pig serum or tissues, in a dose-dependent manner. NF-kB was highly-expressed in AR guinea pigs and down-regulated after APS treatment. NF-kB overexpression facilitated inflammatory responses and Treg/Th17 imbalance in AR.

CONCLUSION

APS reduced Treg/Th17 imbalance via suppressing NF-kB expression, thereby ameliorating inflammatory responses in AR.

TGF-β/Smad Signaling Pathway in Tubulointerstitial Fibrosis

Chronic kidney disease (CKD) was a major public health problem worldwide. Renal fibrosis, especially tubulointerstitial fibrosis, is final manifestation of CKD. Many studies have demonstrated that TGF-β/Smad signaling pathway plays a crucial role in renal fibrosis. Therefore, targeted inhibition of TGF-β/Smad signaling pathway can be used as a potential therapeutic measure for tubulointerstitial fibrosis. At present, a variety of targeting TGF-β1 and its downstream Smad proteins have attracted attention. Natural products used as potential therapeutic strategies for tubulointerstitial fibrosis have the characteristics of acting on multiple targets by multiple components and few side effects. With the continuous research and technique development, more and more molecular mechanisms of natural products have been revealed, and there are many natural products that inhibited tubulointerstitial fibrosis via TGF-β/Smad signaling pathway. This review summarized the role of TGF-β/Smad signaling pathway in tubulointerstitial fibrosis and natural products against tubulointerstitial fibrosis by targeting TGF-β/Smad signaling pathway. Additionally, many challenges and opportunities are presented for inhibiting renal fibrosis in the future.

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.

Astragalus Polysaccharide Reduces Blood Pressure, Renal Damage, and Dysfunction Through the TGF-β1-ILK Pathway

Background:Astragalus polysaccharide extract (APS) has been shown to exhibit antioxidant and anti-inflammatory potential in the treatment of several diseases. However, whether APS could protect against renal damage in hypertensive mice is unknown.

Methods: Hematoxylin and eosin staining, immunohistochemistry, real-time polymerase chain reaction, and Western blotting were used to investigate the effect of APS on the renal damage in deoxycorticosterone acetate- (DOCA) salt- and angiotensin II- (Ang II-) induced hypertensive mice and to elucidate the underlying mechanisms.

Results: Our data demonstrated that APS significantly reduced blood pressure in DOCA-salt- and Ang II-treated mice. Furthermore, APS reduced the inflammatory response and renal fibrosis, thereby improving renal function. Furthermore, the levels of serum creatinine, urea nitrogen, and uric acid increased in DOCA-salt-treated mice, alleviated by APS administration. At the molecular level, DOCA-salt and Ang II increased the mRNA levels of IL-1β, IL-6, α-SMA, collagen I, and collagen III, while APS significantly inhibited these effects. APS inhibited the TGF-β1/ILK signaling pathway, which was activated in hypertensive mice due to the administration of DOCA-salt.

Conclusion: Our results suggest that APS plays a beneficial role in improving renal dysfunction in hypertensive mice.

Effect of traditional Chinese medicine on gut microbiota in adults with type 2 diabetes: A systematic review and meta-analysis

BACKGROUND

Despite advances in research on type 2 diabetes mellitus (T2DM) with the development of science and technology, the pathogenesis and treatment response of T2DM remain unclear. Recent studies have revealed a significant role of the microbiomein the development of T2DM, and studies have found that the gut microbiota may explain the therapeutic effect of traditional Chinese medicine (TCM), a primary branch of alternative and complementary medicine, in the treatment of T2DM. The aim of this study was to systematically review all randomized controlled trials (RCTs) on TCM for gut microbiota to assess the effectiveness and safety of TCM in T2DM patients.

METHODS

All RCTs investigating the effects of TCM interventions on modulating gut microbiota and improving glucose metabolism in the treatment of T2DM adults were included. Meta-analyses were conducted when sufficient data were available, other results were reported narratively. The study protocol was pre-specified, documented, and published in PROSPERO (registration no. CRD42020188043).

RESULTS

Five studies met the eligibility criteria ofthe systematic review. All five studies reported the effects of TCM interventions on the gut microbiota modulation and blood glucose control. There were statistically significant improvements in HbA1c (mean difference [MD]: -0.69%; [95% CI -0.24, -0.14]; p = 0.01, I² = 86%), fasting blood glucose (MD: -0.87 mmol/l; [95% CI -1.26, -0.49]; p < 0.00001, I² = 75%) and 2-h postprandial blood glucose(MD: -0.83mmol/l; [95% CI: -1.01, -0.65]; p < 0.00001, I² = 0%). In addition, there were also statistically significant improvements in homeostasis model assessment of insulin resistance (HOMA-IR) (standardized mean difference [SMD]: -0.99, [95% CI -1.25 to -0.73]; p < 0.00001, I² = 0%) and homeostasis model assessment of β-cell function (HOMA-β) (SMD: 0.54, [95% CI 0.21 to 0.87]; p = 0.001, I² = 0%).There was a significant change in the relative abundance of bacteria in the genera Bacteroides (standardized mean difference [SMD] 0.87%; [95% CI 0.58, 1.16], however, the change in Enterococcus abundance was not statistically significant (SMD: -1.71%; [95% CI: -3.64, 0.23]; p = 0.08) when comparing TCM supplementaltreatment with comparator groups. Other changes in the gut microbiota, including changes in the relative abundances of some probiotics and opportunistic pathogens at various taxon levels, and changes in diversity matrices (α and β), were significant by narrative analysis. However, insufficient evidences were found to support that TCM intervention had an effect on inflammation.

CONCLUSION

TCM had the effect of modulating gut microbiota and improving glucose metabolisms in T2DM patients. Although the results of the included studies are encouraging, further well-conducted studies on TCM interventions targeting the gut microbiota are needed.

Based on Network Pharmacology and Molecular Docking to Explore the Underlying Mechanism of Huangqi Gegen Decoction for Treating Diabetic Nephropathy

Background

Huangqi Gegen decoction (HGD), a Chinese herb formula, has been widely used to treat diabetic nephropathy in China, while the pharmacological mechanisms are still unclear. Therefore, the present study aims to explore the underlying mechanism of HGD for treating diabetic nephropathy (DN).

Materials and Methods

Traditional Chinese Medicine Systems Pharmacology Database (TCMSP), UniProt, and SwissTargetPrediction databases were used to search the active ingredients and potential targets of HGD. In addition, multiple disease-related databases were used to collect DN-related targets. Common targets of the protein-protein interaction (PPI) network were established using the STRING database. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using the DAVID database. At last, AutoDockVina was used to conduct molecular docking verification for the core components and targets.

Results

A total of 27 active ingredients and 354 putative identified target genes were screened from HGD, of which 99 overlapped with the targets of DN and were considered potential therapeutic targets. Further analysis showed that the HGD activity of quercetin, formononetin, kaempferol, isorhamnetin, and beta-sitosterol ingredients is possible through VEGFA, IL6, TNF, AKT1, and TP53 targets involved in TNF, toll-like receptors, and MAPK-related pathways, which have anti-inflammatory, antiapoptosis, antioxidation, and autophagy effects, relieve renal fibrosis and renal cortex injury, and improve renal function, thus delaying the development of DN. The molecular docking results showed that quercetin, formononetin, kaempferol, isorhamnetin, beta-sitosterol had a good binding activity with VEGFA, IL6, TNF, AKT1, and TP53.

Conclusion

This study demonstrated that HGD might take part in the treatment of DN through multicomponent, multitarget, and multichannel combined action.