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

Polysaccharides from Sacha Inchi shell reduces renal fibrosis in mice by modulating the TGF-β1/Smad pathway and intestinal microbiota

Renal fibrosis is a common pathway involved in the progression of various chronic kidney to end-stage diseases, posing a substantial global public health challenge in the search for effective and safe treatments. This study investigated the effects and mechanisms of sacha inchi shell polysaccharide (SISP) on renal fibrosis induced by a high-salt diet (HSD) in mice. By analysing kidney-related protein pathways and the structure of gut microbiota, we found that SISP significantly reduced urinary protein levels induced by a HSD from 41.08 to 22.95 μg/mL and increased urinary creatinine from 787.43 to 1294.50 μmol/L. It reduced renal interstitial collagen fibres by 11.30 %, thereby improving the kidney function. SISP lowered the mRNA expression of TGF-B1, fibronectin, α-SMA, Smad2/3, and TGFBRII, leading to decreased protein levels of TGF-β1, p-Smad2/3, p-TGFβRII, fibronectin, α-SMA, p-Smad2/3/Smad2/3, and p-TGFβRII/TGFβRII. These changes blocked downstream transcription in the TGF-β1/Smad signalling pathway, thereby attenuating renal fibrosis in HSD mice. In addition, SISP altered the intestinal flora imbalance in HSD mice by reducing the relative abundance of the genera, Akkermansia, Faecalibaculum, and unidentified_Ruminococcaceae, and reversing the decline in the levels of the genera, Lactobacillus and Bacteroides. In conclusion, SISP is a promising nutraceutical for renal fibrosis management.

Natural polysaccharides as promising reno-protective agents for the treatment of various kidney injury

Renal injury, a prevalent clinical outcome with multifactorial etiology, imposes a substantial burden on society. Currently, there remains a lack of effective management and treatments. Extensive research has emphasized the diverse biological effects of natural polysaccharides, which exhibit promising potential for mitigating renal damage. This review commences with the pathogenesis of four common renal diseases and the shared mechanisms underlying renal injury. The renoprotective roles of polysaccharides in vivo and in vitro are summarized in the following five aspects: anti-oxidative stress effects, anti-apoptotic effects, anti-inflammatory effects, anti-fibrotic effects, and gut modulatory effects. Furthermore, we explore the structure-activity relationship and bioavailability of polysaccharides in relation to renal injury, as well as investigate their utility as biomaterials for alleviating renal injury. The clinical experiments of polysaccharides applied to patients with chronic kidney disease are also reviewed. Broadly, this review provides a comprehensive perspective on the research direction of natural polysaccharides in the context of renal injury, with the primary aim to serve as a reference for the clinical development of polysaccharides as pharmaceuticals and prebiotics for the treatment of kidney diseases.

Add-on astragalus in type 2 diabetes and chronic kidney disease: A multi-center, assessor-blind, randomized controlled trial

BACKGROUND

Diabetes leads to chronic kidney disease (CKD) and kidney failure, requiring dialysis or transplantation. Astragalus, a common herbal medicine and US pharmacopeia-registered food ingredient, is shown kidney protective by retrospective and preclinical data but with limited long-term prospective clinical evidence. This trial aimed to assess the effectiveness of astragalus on kidney function decline in macroalbuminuric diabetic CKD patients.

METHODS

This randomized, assessor-blind, standard care-controlled, multi-center clinical trial randomly assigned 118 patients with estimated glomerular filtration rate (eGFR) of 30-90 ml/min/1.73m2 and urinary albumin-to-creatinine ratio (UACR) of 300-5000 mg/g from 7 public outpatient clinics and the community in Hong Kong between July 2018 and April 2022 to add-on oral astragalus granules (15 gs of raw herbs daily equivalent) or to continue standard care alone as control for 48 weeks. Primary outcomes were the slope of change of eGFR (used for sample size calculation) and UACR of the intention-to-treat population. Secondary outcomes included endpoint blood pressures, biochemistry, biomarkers, concomitant drug change and adverse events. (ClinicalTrials.gov: NCT03535935) RESULTS: During the 48-week period, the estimated difference in the slope of eGFR decline was 4.6 ml/min/1.73m2 per year (95 %CI: 1.5 to 7.6, p = 0.003) slower with astragalus. For UACR, the estimated inter-group proportional difference in the slope of change was insignificant (1.14, 95 %CI: 0.85 to 1.52, p = 0.392). 117 adverse events from 31 astragalus-treated patients and 41 standard care-controlled patients were documented. The 48-week endpoint systolic blood pressure was 7.9 mmHg lower (95 %CI: -12.9 to -2.8, p = 0.003) in the astragalus-treated patients. 113 (96 %) and 107 (91 %) patients had post-randomization and endpoint primary outcome measures, respectively.

CONCLUSION

In patients with type 2 diabetes, stage 2 to 3 CKD and macroalbuminuria, add-on astragalus for 48 weeks further stabilized kidney function on top of standard care.

Efficacy and potential mechanisms of the main active ingredients of astragalus mongholicus in animal models of liver fibrosis: A systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Astragalus mongholicus (AM) is a Qi-tonifying and immune-regulating herb widely used in traditional Chinese medicine (TCM), which is increasingly regarded as a profound complementary medication in the treatment of fibrosis disease. Astragaloside (AS), astragaloside flavonoids (AF) and astragaloside polysaccharides (APS) are the main active ingredients of Astragalus Mongholicus (AM) that have a significant therapeutic effect on liver fibrosis.

AIM OF THE STUDY

This systematic review and meta-analysis aims to evaluate the effects and possible mechanisms of the main active ingredients of AM including astragaloside (AS), astragalus flavone (AF) and astragalus polysaccharide (APS) in animal models of liver fibrosis.

MATERIALS AND METHODS

We systematically searched ten databases PubMed, Web of Science, Embase, Scopus, CINAHL, ProQuest database, China National Knowledge Internet (CNKI), VIP Information Chinese Periodical Service Platform (VIP), WangFang database and China Biology Medicine Disc (CBM) to identify relevant animal studies from inception to November 2022. The SYRCLE's risk of bias tool was used to assess the methodological quality. The statistical analysis was performed using RevMan 5.4 software.

RESULTS

Twenty-three studies involving 482 animals were included. Studies quality scores ranged from 4 to 5. Alanine aminotransferase (ALT) (SMD, -3.87; 95% CI, -5.09 to -2.65; P < 0.00001) aminotransferase (AST) (SMD, -4.43; 95% CI, -5.77 to -3.08; P < 0.00001), hydroxyproline (HYP) (SMD, -2.94; 95% CI, -3.83 to -2.05; P < 0.00001) and transforming growth factor-β1 (TGF-β1) (SMD, -2.82; 95% CI, -3.57 to -2.06; P < 0.00001) were the main outcome measures to be analyzed. The meta-analysis revealed that the main active ingredients of AM lowered the levels of known risk factors including liver index (SMD, -1.25; 95% CI, -1.63 to -0.87; P < 0.00001), degree of liver fibrosis (SMD, -1.93; 95% CI, -2.57 to -1.28; P < 0.00001), collagen α type I (Col)-1 (SMD, -3.71; 95% CI, -5.63 to -1.79; P = 0.0001), hyaluronic acid (HA) (SMD, -2.65; 95% CI, -3.69 to -1.61; P < 0.00001), laminin (LN) (SMD, -2.06; 95% CI, -2.51 to -1.61; P < 0.00001), type IV collagen (CIV) (SMD, -3.04; 95% CI, -4.34 to -1.74; P < 0.00001), procollagen typeIII (PCIII) (SMD, -2.60; 95% CI, -3.15 to -2.05; P < 0.00001), albumin (ALB) (SMD, -1.19; 95% CI, -1.63 to -0.75; P < 0.00001), total bilirubin (TBiL) (SMD, -3.63; 95% CI, -5.39 to -1.88; P < 0.0001), α-smooth muscle actin (α-SMA) (SMD, -5.27; 95% CI, -6.94 to -3.61; P < 0.00001) and Smad3 (SMD, -4.11; 95% CI, -7.17 to -1.05; P = 0.009) level.

CONCLUSION

Our meta-analysis demonstrates the effective role of the main active ingredients of AM in preclinical studies of liver fibrosis. The underlying mechanisms may be related to attenuation of oxidative stress, modulation of inflammatory response and inhibition of collagen production. However, due to the significant heterogeneity and poor quality of included studies, positive findings should be treated cautiously.

REGISTRATION

PROSPERO ID CRD42023382282.

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.

Derivation and elimination of uremic toxins from kidney-gut axis

Uremic toxins are chemicals, organic or inorganic, that accumulate in the body fluids of individuals with acute or chronic kidney disease and impaired renal function. More than 130 uremic solutions are included in the most comprehensive reviews to date by the European Uremic Toxins Work Group, and novel investigations are ongoing to increase this number. Although approaches to remove uremic toxins have emerged, recalcitrant toxins that injure the human body remain a difficult problem. Herein, we review the derivation and elimination of uremic toxins, outline kidney-gut axis function and relative toxin removal methods, and elucidate promising approaches to effectively remove toxins.

Renal protective effects of astragalus root in rat models of chronic kidney disease

BACKGROUND

Astragalus root is a commonly used herb in traditional Chinese medicine. Although renoprotective effects have been reported in some clinical and experimental studies, the details remain unknown.

METHODS

We used 5/6 nephrectomized rats as chronic kidney disease (CKD) models. At 10 weeks, they were divided into four groups, namely, CKD, low-dose astragalus (AR400), high-dose astragalus (AR800), and sham groups. At 14 weeks, they were sacrificed for the evaluation of blood, urine, mRNA expression in the kidney, and renal histopathology.

RESULTS

Kidney dysfunction was significantly improved following astragalus administration (creatinine clearance: sham group; 3.8 ± 0.3 mL/min, CKD group; 1.5 ± 0.1 mL/min, AR400 group; 2.5 ± 0.3 mL/min, AR800 group; 2.7 ± 0.1 mL/min). Blood pressure, urinary albumin, and urinary NGAL levels were significantly lower in the astragalus-treated groups than those in the CKD group. Excretion of urinary 8-OHdG, an oxidative stress marker, and intrarenal oxidative stress were lower in the astragalus-treated groups than those in the CKD group. Furthermore, the mRNA expression of NADPH p22 phox, NADPH p47 phox, Nox4, renin, angiotensin II type 1 receptor, and angiotensinogen in the kidney was lower in the astragalus-treated groups compared with the CKD group.

CONCLUSION

This study suggests that astragalus root slowed CKD progression, possibly through the suppression of oxidative stress and the renin-angiotensin system.

Fufang shenhua tablet, astragali radix and its active component astragaloside IV: Research progress on anti-inflammatory and immunomodulatory mechanisms in the kidney

Background: Given the limited treatment options available for kidney disease, a significant number of patients turn to alternative therapies, including traditional Chinese medicine. Among these therapies, the Fufang Shenhua tablet (SHT) has garnered attention for its effectiveness in addressing the most common deficiency of Qi and Yin in chronic glomerulonephritis. Notably, the sovereign drug of SHT is Astragali Radix (AR), with the most abundant and effective component being Astragaloside IV (AS-IV). AS-IV has been shown to possess anti-inflammatory and immunomodulatory properties, and it is extensively used in treating kidney diseases. Nevertheless, the molecular mechanisms underlying its action are numerous and intricate, and a comprehensive understanding is yet to be achieved. Aim of the review: Thus, we have thoroughly examined the existing research and outlined the advancements made in investigating the anti-inflammatory and immunomodulatory mechanisms of SHT, AR and its active component AS-IV, in relation to kidney health. This serves as a dependable foundation for conducting more comprehensive investigations, evaluating efficacy, and making further improvements in the future. Materials and methods: We conducted a comprehensive literature search utilizing multiple globally recognized databases, including Web of Science, Google Scholar, PubMed, ScienceDirect, Wiley, ACS, Springer, and CNKI. The search keywords used in this study were "Fufang Shenhua tablet," "Astragali Radix," "Astragaloside IV," and "Anti-inflammatory" or "Immunity." Results: The mechanism of inflammation inhibition by SHT, AR and its active component AS-IV is mainly related to the signaling pathways such as NF-κB, TLRs, PI3K/AKT, Wnt/β-catenin, and JAK-STAT. Immunomodulation exerts not only activating, stimulating, and regulating effects on macrophages and dendritic cells, but also on immune organs, T-lymphocytes, B-lymphocytes, and a myriad of cytokines. Moreover, the SHT, AR and its active component AS-IV also demonstrate regulatory effects on renal cells, including glomerular mesangial cells, tubular epithelial cells, and podocytes. Conclusion: To summarize, SHT, AR and its active component AS-IV, exhibit notable therapeutic effects in kidney-related ailments, and their molecular mechanisms for anti-inflammatory and immunomodulatory effects have been extensively explored. However, further standard clinical trials are necessary to evaluate their safety and efficacy in the adjunctive treatment of kidney-related diseases. Moreover, in-depth studies of unverified chemical components and regulatory mechanisms in SHT are required. It is our belief that with continued research, SHT, AR and its active component AS-IV are poised to pave the way for enhancing therapeutic outcomes in kidney-related ailments.

Ganoderma lucidum polysaccharide inhibits HSC activation and liver fibrosis via targeting inflammation, apoptosis, cell cycle, and ECM-receptor interaction mediated by TGF-β/Smad signaling

BACKGROUND

Ganoderma lucidum polysaccharide (GLP) has many biological properties, however, the anti-fibrosis effect of GLP is unknown at present.

PURPOSE

This study aimed to examine the anti-fibrogenic effect of GLP and its underlying molecular mechanisms in vivo and in vitro.

STUDY DESIGN

Both CCl₄-induced mouse and TGF-β1-induced HSC-T6 cellular models of fibrosis were established to examine the anti-fibrogenic effect of a water-soluble GLP (25 kDa) extracted from the sporoderm-removed spores of G. lucidum..

METHOD

Serum markers of liver injury, histology and fibrosis of liver tissues, and collagen formation were examined using an automatic biochemical analyzer, H&E staining, Sirius red staining, immunohistochemistry, immunofluorescence, ELISA, Western blotting, and qRT-PCR. RNA-sequencing, enrichment pathway analysis, Western blotting, qRT-PCR, and flow cytometry were employed to identify the potential molecular targets and signaling pathways that are responsible for the anti-fibrotic effect of GLP.

RESULTS

We showed that GLP (150 and 300 mg/kg) significantly inhibited hepatic fibrogenesis and inflammation in CCl₄-treated mice as mediated by the TLR4/NF-κB/MyD88 signaling pathway. We further demonstrated that GLP significantly inhibited hepatic stellate cell (HSCs) activation in mice and in TGF-β1-induced HSC-T6 cells as manifested by reduced collagen I and a-SMA expressions. RNA-sequencing uncovered inflammation, apoptosis, cell cycle, ECM-receptor interaction, TLR4/NF-κB, and TGF-β/Smad signalings as major pathways suppressed by GLP administration. Further studies demonstrated that GLP elicits anti-fibrotic actions that are associated with a novel dual effect on apoptosis in vivo (inhibit) or in vitro (promote), suppression of cell cycle in vivo, induction of S phase arrest in vitro, and attenuation of ECM-receptor interaction-associated molecule expressions including integrins ITGA6 and ITGA8. Furthermore, GLP significantly inhibited the TGF-β/Smad signaling in mice, and reduced TGF-β1 or its agonist SRI-011381-induced Smad2 and Smad3 phosphorylations, but increased Samd7 expression in HSC-T6 cells.

CONCLUSION

This study provides the first evidence that GLP could be a promising dietary strategy for treating liver fibrosis, which protects against liver fibrosis and HSC activation through targeting inflammation, apoptosis, cell cycle, and ECM-receptor interactions that are mediated by TGF-β/Smad signaling.

Astragalus and its formulas as a therapeutic option for fibrotic diseases: Pharmacology and mechanisms

Fibrosis is the abnormal deposition of extracellular matrix, characterized by accumulation of collagen and other extracellular matrix components, which causes organ dysfunction and even death. Despite advances in understanding fibrosis pathology and clinical management, there is no treatment for fibrosis that can prevent or reverse it, existing treatment options may lead to diarrhea, nausea, bleeding, anorexia, and liver toxicity. Thus, effective drugs are needed for fibrotic diseases. Traditional Chinese medicine has played a vital role in fibrotic diseases, accumulating evidence has demonstrated that Astragalus (Astragalus mongholicus Bunge) can attenuate multiple fibrotic diseases, which include liver fibrosis, pulmonary fibrosis, peritoneal fibrosis, renal fibrosis, cardiac fibrosis, and so on, mechanisms may be related to inhibition of epithelial-mesenchymal transition (EMT), reactive oxygen species (ROS), transforming growth factor beta 1 (TGF-β1)/Smads, apoptosis, inflammation pathways. The purpose of this review was to summarize the pharmacology and mechanisms of Astragalus in treating fibrotic diseases, the data reviewed demonstrates that Astragalus is a promising anti-fibrotic drug, its main anti-fibrotic components are Calycosin, Astragaloside IV, Astragalus polysaccharides and formononetin. We also review formulas that contain Astragalus with anti-fibrotic effects, in which Astragalus and Salvia miltiorrhiza Bunge, Astragalus and Angelica sinensis (Oliv.) Diels are the most commonly used combinations. We propose that combining active components into new formulations may be a promising way to develop new drugs for fibrosis. Besides, we expect Astragalus to be accepted as a clinically effective method of treating fibrosis.

Astragalus polysaccharide alleviates ulcerative colitis by regulating the balance of Tfh/Treg cells

The immunomodulatory function of natural active ingredients has long been a focus of scientific research, with recent hotspots reporting targeted modulation of the follicular helper T cells (Tfh)/regulatory T cells (Treg) balance as an emerging strategy for the treatment of ulcerative colitis (UC). Here, dextran sodium sulfate induced mice UC and Astragalus polysaccharide (APS, 200 mg/kg/day) was administered simultaneously. In this study, APS effectively alleviated colitis in mice by improving survival rate, disease activity index (DAI), the change rate of body weight, colonic length and weight, and histopathological injury of the colon. Moreover, APS regulated the expression of inflammatory cytokines interleukin (IL)-2, IL-6, IL-12p70, IL-23, Tumour necrosis factor (TNF)-ɑ, and transforming growth factor (TGF)-β1 in colonic tissues of colitis mice. Importantly, APS significantly downregulated Tfh cell and the expression of its related nuclear transcription factors Blimp-1 and Bcl-6, and cytokine IL-21. Meanwhile, APS regulated the differentiation of Tfh subpopulations in colitis mice, with Tfh10 and Tfr significantly upregulated while Tfh1, Tfh17, and Tfh21 significantly downregulated. In addition, APS significantly upregulated Treg cells and the levels of its associated nuclear transcription factor Foxp3, and cytokine IL-10 in colitis mice. In conclusion, APS effectively alleviated UC by reshaping the balance of Tfh/Treg cells.

Heidihuangwan alleviates renal fibrosis in rats with 5/6 nephrectomy by inhibiting autophagy

Renal fibrosis is a common pathway for the progression of various chronic kidney diseases (CKD), and the formation and deterioration will eventually lead to end-stage renal failure, which brings a heavy medical burden to the world. HeidihuangWan (HDHW) is a herbal formulation with stable and reliable clinical efficacy in the treatment of renal fibrosis. However, the mechanism of HDHW in treating renal fibrosis is not clear. In this study, we aimed to investigate the mechanism of HDHW to improve renal fibrosis. Wistar rats were randomly divided into the normal control group, 5/6 Nephrectomy group, astragaloside IV (AS-IV) group, HDHW group, and HDHW + IGF-1R inhibitor (JB1) group. Except for the normal control group, the rat renal fibrosis model was established by 5/6 nephrectomy and intervened with drugs for 8 weeks. Blood samples were collected to evaluate renal function. Hematoxylin-Eosin (HE), Periodic Acid-Schiff (PAS), Modified Masson’s Trichrome (Masson) staining were used to evaluate the pathological renal injury, and immunohistochemistry and Western blotting were used to detect the protein expression of renal tissue. The results showed that HDHW was effective in improving renal function and reducing renal pathological damage. HDHW down-regulated the levels of fibrosis marker proteins, including α-smooth muscle actin (α-SMA), vimentin, and transforming growth factors–β(TGF-β), which in turn reduced renal fibrosis. Further studies showed that HDHW down-regulated the expression of autophagy-related proteins Beclin1 and LC3II, indicating that HDHW inhibited autophagy. In addition, we examined the activity of the class I phosphatidylinositol-3 kinase (PI3K)/serine-threonine kinase (Akt)/mTOR pathway, an important signaling pathway regulating autophagy, and the level of insulin-like growth factor 1 (IGF-1), an upstream activator of PI3K/Akt/mTOR. HDHW upregulated the expression of IGF-1 and activated the PI3K/Akt/mTOR pathway, which may be a vital pathway for its inhibition of autophagy. Application of insulin-like growth factor 1 receptor (IGF-1R) inhibitor further confirmed that the regulation of autophagy and renal fibrosis by HDHW was associated with IGF-1-mediated activation of the PI3K/Akt/mTOR pathway. In conclusion, our study showed that HDHW inhibited autophagy by upregulating IGF-1 expression, promoting the binding of IGF-1 to IGF-1R, and activating the PI3K/Akt/mTOR signaling pathway, thereby reducing renal fibrosis and protecting renal function. This study provides support for the application and further study of HDHW.