FTZ polysaccharides ameliorate kidney injury in diabetic mice by regulating gut-kidney axis

Ligusticum cycloprolactam ameliorates hyperuricemic nephropathy through inhibition of TLR4/NF-κB signaling

Hyperuricemia is a metabolic disease attributed to a sustained dysregulation of purine metabolism, manifesting as consistently elevated blood uric acid levels. Hyperuricemic nephropathy (HN) is a renal complication of hyperuricemia. It is characterized by the deposition of urate crystals, inflammatory cell infiltration and tubulointerstitial injury. Ligusticum cycloprolactam (LIGc) is a novel monomeric derivative of the active ingredient ligustilide (LIG) from Angelica sinensis (Oliv.). LIG demonstrates anti-inflammatory and antioxidant properties. Nevertheless, the therapeutic potential of LIGc to ameliorate HN required further investigation. Our study revealed that LIGc effectively reduced serum uric acid and attenuated HN in mice induced by co-administering potassium oxonate and hypoxanthine. Our research demonstrated that LIGc treatment improved renal function in mice with HN by regulating the expression of uric acid transporters. Histopathological analysis showed that LIGc treatment reduced tubular damage, inflammatory infiltration and interstitial collagen deposition. Mechanistically, LIGc alleviated renal injury by inhibiting the TLR4/NF-κB signaling pathway both in vivo and in vitro. Our study revealed that LIGc effectively mitigated HN by attenuating the inflammatory response through the TLR4/NF-κB signaling pathway, providing new perspectives for the treatment of HN.

Curcumin alleviates atrazine-induced nephrotoxicity by enhancing mitophagy through PINK1/Parkin signaling pathway in mice

Atrazine (ATR), a widely used herbicide, poses significant environmental and health risks due to its high solubility and adsorption in soil. ATR exposure can lead to nephrotoxicity in humans and animals. Curcumin (Cur), an active compound in Curcuma species, is renowned for its antioxidant and anti-inflammatory properties, with potential to mitigate chronic disease risks. We hypothesized that the addition of Cur could alleviate renal impairment associated with ATR exposure and carried out experiments using mice as subjects. This study investigates whether Cur can attenuate ATR-induced nephrotoxicity in mice by modulating mitophagy and apoptotic pathways. Our findings illustrate that consumption with Cur attenuates nephrotoxicity induced by ATR, as evidenced by lowered serum concentrations of uric acid (UA), blood urea nitrogen (BUN), and creatinine (CRE), established biomarkers of renal injury. Moreover, Curcumin enhances renal antioxidant defense mechanisms in ATR-exposed mice, as indicated by elevated levels of total antioxidant capacity (T-AOC), catalase (CAT), and glutathione peroxidase (GSH-Px), alongside reduced levels of malondialdehyde (MDA). Histopathological and electron microscopy analyses further corroborate these findings, showing reduced organelle damage, particularly mitochondrial ridge breakage and vacuolization, and increased autophagic lysosomes. Cur further enhances PINK1/Parkin-mediated autophagy, as evidenced by elevated levels of PINK1, Parkin, LC3BII, and P62 compared to ATR-treated mice. Moreover, Cur mitigates the mitochondrial apoptotic pathway, indicated by the down-regulation of apoptosis-related genes (Cytochrome C (Cyto-C), Caspase3, Caspase9) and the pro-apoptotic marker (Bax), along with the up-regulation of the anti-apoptotic marker (Bcl-2) at both transcriptional and translational levels compared to ATR-treated mice. In summary, Cur demonstrates nephroprotective properties against ATR-induced injury through the enhancement of mitochondrial autophagy and display of anti-apoptotic actions, underscoring its curative potency as a treatment for nephrotoxicity caused by ATR.

Gut Microbiota and Their Metabolites: The Hidden Driver of Diabetic Nephropathy? Unveiling Gut Microbe's Role in DN

BACKGROUND

Diabetic nephropathy (DN) is a severe microvascular complication of diabetes with a complex pathogenesis.

METHODS

Recent studies were reviewed to explore the role of gut microbiota and its metabolites in DN development.

RESULTS

Dysbiosis of gut bacteria contributes to pathological changes such as glomerular sclerosis and renal tubule injury. Microbial metabolites are involved in DN through immune and inflammatory pathways.

CONCLUSIONS

Understanding the relationship between gut microbiota, its metabolites, and DN may offer potential implications for DN diagnosis, prevention, and treatment. Translating this knowledge into clinical practice presents challenges and opportunities.

Discussion on the treatment of diabetic kidney disease based on the "gut-fat-kidney" axis

Diabetic kidney disease is the main cause of end-stage renal disease, and its prevention and treatment are still a major clinical problem. The human intestine has a complex flora of hundreds of millions of microorganisms, and intestinal microorganisms, and their derivatives are closely related to renal inflammatory response, immune response, and material metabolism. Brown adipose tissue is the main part of adaptive thermogenesis. Recent studies have shown that activating brown fat by regulating intestinal flora has good curative effects in diabetic kidney disease-related diseases. As an emerging medical concept, the "gut-fat-kidney" axis has received increasing attention in diabetic kidney disease and related diseases. However, the specific mechanism involved needs further study. A new theoretical basis for the prevention and treatment of diabetic kidney disease is presented in this article, based on the "gut-fat-kidney" axis.

Dietary phytosterol supplementation mitigates renal fibrosis via activating mitophagy and modulating the gut microbiota

Chronic kidney disease (CKD) poses a significant global health challenge, primarily driven by renal fibrosis, with limited treatment options. Addressing this condition necessitates either targeted medical treatments or dietary interventions. Phytosterols (PS) are cholesterol-like bioactive compounds in various plant-based foods with antioxidant and anti-inflammatory effects. A CKD mouse model was established using folic acid (FA) and treated with dietary supplements of two PS, stigmasterol (Stig) and β-sitosterol (β-Sito). The effects and mechanisms of PS were investigated through biochemical indices, pathology, transcriptomics, and 16S rDNA sequencing. The results indicated that high-dose PS are more effective than low-dose PS and Losartan potassium (LP) in reducing renal fibrosis, restoring function, and modulating oxidative stress and inflammation, with no significant differences between high-dose Stig and β-Sito treatments. Gene Ontology (GO) enrichment analysis revealed that PS were significantly enriched in pathways related to the mitochondrial outer membrane, ubiquitin-protein ligase binding, and other cellular components and molecular processes. PS reduced the expression of TGF-β/Smad and cGAS/Sting1/TBK1 and activated PINK1/Parkin pathway proteins, thereby mitigating renal fibrosis in mice. CKD is often associated with imbalanced gut microbiota and compromised intestinal barriers. Our observations indicated that PS restored the intestinal barrier, altered the composition of the gut microbiota, and improved renal function in CKD mice. The present findings indicate that both Stig and β-Sito activate mitophagy via the PINK1/Parkin pathway and modulate the gut microbiota, thereby alleviating renal fibrosis. The findings provide solid and significant implications for developing effective application of PS supplementation in the management of CKD, presenting novel concepts and approaches for research and clinical treatment.

Renshen Zhuye decoction ameliorates high-fat diet-induced obesity and insulin resistance by modulating gut microbiota and metabolic homeostasis

BACKGROUND

Obesity, characterized by excessive adipose tissue accumulation, has become a global health challenge with rapidly increasing prevalence. It contributes significantly to metabolic disorders including insulin resistance (IR). Renshen-zhuye decoction (RZD), a traditional Chinese medicine formula historically used for diabetes, shows potential for improving metabolic parameters, but its effects and mechanisms in obesity and insulin resistance remain unclear.

PURPOSE

This study aimed to evaluate the therapeutic benefits of RZD on obesity and insulin resistance, and to elucidate the underlying mechanisms through which it improves glucose and lipid metabolism.

METHODS

The role of RZD was evaluated in a high-fat diet (HFD) mouse model. The formula was characterized using UPLC-MS. Comprehensive analyses including histopathological staining, immunofluorescence, biochemical assays, 16S rRNA gene sequencing of gut microbiota, and non-targeted metabolomic analysis were performed. To validate the role of gut microbiota, we employed antibiotic treatment (ABX) to deplete intestinal flora and conducted fecal microbiota transplantation (FMT) experiments.

RESULTS

RZD treatment dose-dependently alleviated HFD-induced dyslipidemia and insulin resistance, improving glucose tolerance, insulin sensitivity, and energy expenditure. Gut microbiota analysis revealed that RZD significantly modulated the composition of intestinal flora and their metabolic profiles. Additionally, RZD reduced intestinal and systemic inflammation by enhancing intestinal barrier integrity, particularly through increased expression of tight junction proteins such as Occludin. Importantly, the beneficial effects of RZD on weight management and glucose homeostasis were antagonized by antibiotic intervention, while FMT experiments confirmed that these improvements were mediated through gut microbiota modulation.

CONCLUSION

This study provides new insights into RZD's modulatory effects on gut microbiota and subsequent improvements in obesity-related metabolic parameters. RZD alleviates HFD-induced obesity and insulin resistance in mice by modulating gut microbiota composition and function, which subsequently improves intestinal barrier integrity, reduces inflammation, and enhances metabolic homeostasis.

Boeravinone C ameliorates lipid accumulation and inflammation in diabetic kidney disease by activating PPARα signaling

ETHNOPHARMACOLOGICAL RELEVANCE

The roots of Oxybaphus himalaicus Edgew. is a traditional Tibetan herbal medicine with kidney reinforcing and tonifying effects, which is commonly applied to treat nephritis. Boeravinone C has been identified as one of the primary constituents of O. himalaicus. However, the potential renal protective effects of boeravinone C remains unclear.

AIM OF THE STUDY

This research aimed to investigate the protective effects of boeravinone C on diabetic kidney disease and the underlying mechanisms.

MATERIALS AND METHODS

Streptozotocin (100 mg/kg) was intraperitoneally injected to induce DKD in mice. High glucose (50 mM)-induced HK-2 cells were utilized to investigate the mechanisms of boeravinone C against tubular injuries in vitro. Anti-DKD activity was assessed by measuring reactive oxygen species (ROS) levels, analyzing apoptosis through flow cytometry, and evaluating inflammation, apoptosis, and FAO-related proteins via Western blotting. Additionally, serum biochemical assays, as well as histopathological and immunohistochemical analyses of kidney tissues, were performed to explore the pharmacological effects of boeravinone C.

RESULTS

In vivo, boeravinone C administered significantly reduced the creatinine (CRE), blood urea nitrogen (BUN), triglycerides (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) levels in serum of DKD mice. In vitro, boeravinone C significantly restored the apoptosis induced by HG in HK-2 cells, which is further validated by an upregulation of the apoptosis-inhibiting protein Bcl-2, along with a decreased expression of the apoptosis-promoting proteins Bax and caspase-3. Mechanistically, boeravinone C reversed HG-induced downregulation of peroxisome proliferator-activated receptor α (PPARα) expression. As a transcription factor, elevated expression of PPARα led to upregulation of CPT1A and ACOX1, which then enhanced fatty acid oxidation (FAO) to reduce lipid accumulation in HK-2 cells. Furthermore, boeravinone C-mediated high expression of PPARα sequestered p65 subunit of NF-κB in the cytoplasm, leading to reduced expression of proinflammatory cytokines such as iNOS, TNF-α and IL-6. To verify that the therapeutic effects of boeravinone C in diabetic kidney disease (DKD) are mediated via PPARα activation, we developed a PPARα knockdown HK-2 cell line. Our findings revealed that PPARα downregulation modified biological effects of boeravinone C, especially regarding fatty acid metabolism and the inflammatory response, with significant repercussions on apoptosis.

CONCLUSION

This study demonstrates that the major component boeravinone C from O. himalaicus promotes the fatty acid oxidation and suppresses inflammatory response by upregulating PPARα expression, thereby reducing apoptosis in HG-induced renal tubule cells. Consequently, boeravinone C restores tubular function in DKD mice. Collectively, this study provides a pharmacological basis for utilizing of O. himalaicus in treating DKD.

Recent insights and advances in gut microbiota's influence on host antiviral immunity

A diverse array of microbial organisms colonizes the human body, collectively known as symbiotic microbial communities. Among the various pathogen infections that hosts encounter, viral infections represent one of the most significant public health challenges worldwide. The gut microbiota is considered an important biological barrier against viral infections and may serve as a promising target for adjuvant antiviral therapy. However, the potential impact of symbiotic microbiota on viral infection remains relatively understudied. In this review, we discuss the specific regulatory mechanisms of gut microbiota in antiviral immunity, highlighting recent advances in how gut microbiota regulate the host immune response, produce immune-related molecules, and enhance the host's defense against viruses. Finally, we also discuss the antiviral potential of oral probiotics.

Proteomics exploration of metformin hydrochloride for diabetic kidney disease treatment via the butanoate metabolism pathway

Diabetic nephropathy (DKD) is a diabetesrelated kidney injury with an increasing incidence every year. Metformin hydrochloride (MET), a cornerstone treatment for glucose lowering, has been widely reported for the treatment of DKD, but the specific molecular mechanisms and potential therapeutic targets still need to be further explored. We used kidney tissues from db/db mice as samples and used proteomics and bioinformatics to analyse the function, distribution and related pathways of differential proteins in DKD, focusing on the assessment of the binding energies of key proteins in the butyrate pathway and drugs at the molecular level, which showed that the expression profiles of differential proteins in kidney tissues were altered after MET treatment, involving energy metabolism. The key proteins involved in the butanoate metabolism pathway, including AACS, ACSM3, EHHADH and HMGCS2, exhibit binding energies to MET of ＜-5 kcal. It is therefore plausible that MET treatment may affect the butanoate metabolism pathway, potentially ameliorating the progression of DKD by modulating mitochondrial function and inflammatory responses.

Associations Between Gut Microbiota and Diabetic Nephropathy: A Mendelian Randomization Study

Objectives

Diabetic nephropathy (DN) is a severe complication of diabetes mellitus, and its pathogenesis remains incompletely understood. Emerging evidence suggests a potential link between gut microbiota and DN. This study aimed to explore the causal relationship between gut microbiota and DN using a two-sample Mendelian randomization (MR) approach.

Methods

Gut microbiota data were obtained from the MiBioGen consortium, which provides the most comprehensive genome-wide association studies (GWAS) on gut microbiota. Summary-level genetic data for DN were sourced from publicly available GWAS data provided by the FinnGen consortium. The primary analysis was conducted using the inverse variance-weighted (IVW) method, complemented by sensitivity analyses to evaluate pleiotropy and heterogeneity.

Results

Fourteen gut microbiota species demonstrated significant genetic associations with DN in the MR analysis, including five negatively and nine positively associated species, as determined by the IVW method. No evidence of pleiotropy or heterogeneity was observed, ensuring the robustness of the findings.

Conclusions

This study provides novel insight into the causal role of gut microbiota in DN pathogenesis, uncovering specific microbial species that may contribute to disease progression. These findings offer a promising avenue for future research and therapeutic development targeting gut microbiota.

The role of fecal microbiota transplantation in type 2 diabetes mellitus treatment

In contemporary microbial research, the exploration of interactions between microorganisms and multicellular hosts constitutes a burgeoning field. The gut microbiota is increasingly acknowledged as a pivotal contributor to various disorders within the endocrine system, encompassing conditions such as diabetes and thyroid diseases. A surge in research activities has been witnessed in recent years, elucidating the intricate interplay between the gut microbiota and disorders of the endocrine system. Simultaneously, fecal microbiota transplantation (FMT) has emerged as a focal point, garnering substantial attention in both biomedical and clinical spheres. Research endeavors have uncovered the remarkable therapeutic efficacy of FMT across diverse diseases, with particular emphasis on its application in addressing type 2 diabetes mellitus (T2DM) and associated com-plications. Consequently, this manuscript accentuates the intimate connection between the gut microbiota and disorders within the endocrine system, with a specific focus on exploring the potential of FMT as an intervention in the therapeutic landscape of T2DM and its complications. Furthermore, the article scrutinizes concerns inherent in treatment modalities centered around the gut microbiota, proposing viable solutions to address these issues.

Exploration of the pathogenesis of nephrotic syndrome and traditional Chinese medicine intervention based on gut microbiota

Nephrotic syndrome (NS) represents a prevalent syndrome among various chronic kidney disease pathologies and is known for its higher severity and worse prognosis compared with chronic glomerulonephritis. Understanding its pathogenesis and identifying more effective treatment modalities have long been a concern of kidney specialists. With the introduction of the gut-kidney axis concept and the progress in omics technologies, alterations in the gut microbiota have been observed in primary and secondary NS. This link has been extensively researched in conditions such as diabetic nephropathy and immunoglobulin A (IgA) nephropathy. Thus, dysbiosis of the gut microbiota is seen as a crucial contributing factor in NS; however, there is a lack of comprehensive reviews that elucidate the changes in the gut microbiota across different NS conditions and that describe its mechanistic role in the disease. Moreover, serving as an innate regulator of the gut microbiota, traditional Chinese medicine (TCM) has the potential to exert a profound impact on the expression of inflammation-promoting agents, decreasing the levels of endotoxins and uremic toxins. In addition, it strengthens the stability of the intestinal barrier while controlling the metabolic function of the body through its efficient modulation of the gut microbiota. This intricate process yields far-reaching consequences for NS.

Fufang Zhenzhu Tiaozhi (FTZ) capsule ameliorates diabetic kidney disease in mice via inhibiting the SGLT2/glycolysis pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Fufang Zhenzhu Tiaozhi (FTZ) capsule is a hospital preparation of a patented traditional Chinese medicine compound. FTZ has been clinically used for nearly 13 years in the treatment of diabetes and glycolipid metabolic diseases. With the significant benefits of SGLT2 inhibitor in patients with diabetic kidney disease (DKD), it provides a research avenue to explore the mechanism of FTZ in treating this disease based on glycolysis pathway.

AIM OF THE STUDY

To explore the pharmacological characteristics of FTZ in DKD mice and its impact on the glycolysis pathway.

MATERIALS AND METHODS

We induced a DKD model in C57BL/6 mice by injection of streptozotocin (STZ) combined with long-term high-fat diet. We administered three doses of FTZ for 12 weeks of treatment. Kidney function, blood lipid levels, glucose tolerance, and key glycolytic enzymes were evaluated. Renal pathological changes were observed using HE, MASSON, and PAS staining. The potential targets of the active ingredients of FTZ in the glycolysis pathway were predicted using network pharmacology and molecular docking. Validation was performed using immunohistochemistry and Western blotting.

RESULTS

FTZ effectively reduces blood glucose, total cholesterol, triglyceride, low density lipoprotein cholesterol, 24 h proteinuria, serum creatinine, blood urea nitrogen, and increases urinary glucose levels. Glucose tolerance and renal pathological changes were significantly improved by FTZ treatment. Pinusolidic acid, a component of FTZ, shows good binding affinity with three active pockets of SGLT2. WB and immunohistochemistry revealed that FTZ significantly inhibits the expression of SGLT2 and its glycolytic related proteins (GLUT2/PKM2/HK2). Hexokinase, pyruvate kinase, and lactate dehydrogenase in the kidney were also significantly inhibited by FTZ in a dose-dependent manner.

CONCLUSION

FTZ may alleviate the progression of DKD by inhibiting the activation of the SGLT2/glycolytic pathway. Our study provides new insights into the clinical application of FTZ in DKD.

Establishment and optimization of a novel mouse model of hyperuricemic nephropathy

Hyperuricemia is a metabolic disorder characterized by elevated serum uric acid levels. Soluble urate can activate immune responses, and the excessive accumulation of urate in the kidneys results in hyperuricemic nephropathy (HN). However, the lack of an established HN model is a major obstacle to advancing research into the pathogenesis of HN and the development of novel drugs. In this study, we generated and evaluated an optimized mouse model of HN by the combined administration of potassium oxonate and hypoxanthine at various dosages. Our results demonstrated that intraperitoneal injection of 200 mg/kg potassium oxonate with gavage of 500 mg/kg hypoxanthine caused renal injury in mice, as evidenced by the elevation in serum uric acid, serum creatinine, and 24 h albuminuria levels, as well as pathological changes in renal histology. Intraperitoneal injection of 200 mg/kg potassium oxonate with gavage of 500 mg/kg hypoxanthine markedly increased the production of uric acid, inhibited uricase activity, and disrupted uric acid transporters. This led to supersaturated urate deposition in the kidneys, triggering renal inflammation and fibrosis, thereby promoting HN progression. In conclusion, we successfully established a stable and efficient mouse model that can mimic the pathogenesis of HN. This novel model may facilitate the discovery of therapeutic targets and the development of new drugs for the treatment of HN.

The Influence and Mechanisms of Natural Plant Polysaccharides on Intestinal Microbiota-Mediated Metabolic Disorders

Natural plant polysaccharides are renowned for their broad spectrum of biological activities, making them invaluable in both the pharmaceutical and food industries. Their safety, characterized by low toxicity and minimal side effects, coupled with their potential therapeutic properties, positions them as crucial elements in health-related applications. The functional effectiveness of these polysaccharides is deeply connected to their structural attributes, including molecular weight, monosaccharide components, and types of glycosidic bonds. These structural elements influence how polysaccharides interact with the gut microbiota, potentially alleviating various metabolic and inflammatory disorders such as inflammatory bowel disease, diabetes, liver-associated pathologies, obesity, and kidney diseases. The polysaccharides operate through a range of biological mechanisms. They enhance the formation of short-chain fatty acids, which are pivotal in keeping intestinal health and metabolic balance. Additionally, they strengthen the intestinal mucosal barrier, crucial for deterring the ingress of pathogens and toxins into the host system. By modulating the immune responses within the gut, they help in managing immune-mediated disorders, and their role in activating specific cellular signaling pathways further underscores their therapeutic potential. The review delves into the intricate structure-activity relationships of various natural polysaccharides and their interactions with the intestinal flora. By understanding these relationships, the scientific community can develop targeted strategies for the use of polysaccharides in therapeutics, potentially leading to innovative treatments for a range of diseases. Furthermore, the insights gained can drive the advancement of research in natural polysaccharide applications, providing direction for novel dietary supplements and functional foods designed to support gut health and overall well-being.

Low molecular weight polysaccharide of Tremella fuciformis exhibits stronger antioxidant and immunomodulatory activities than high molecular weight polysaccharide

Low molecular weight polysaccharides had higher bio-activity and bioavailability compared to ultra-high molecular weight polysaccharides, this study aimed to obtain low molecular weight polysaccharides from Tremella fuciformis (TFLP) by using high-temperature and high-pressure assisted hydrochloric acid method to degrade Tremella fuciformis polysaccharides (TFP), and the structural characteristics, in vivo antioxidant and immune enhancing activities of TFP and TFLP was explored through Caenorhabditis elegans (C. elegans) and mice model. It was found that TFP and TFLP were acidic polysaccharides with molecular weights of 2238 kDa and 3 kDa, respectively. The glycosidic bonding of TFP and TFLP was mainly composed of different configurations of mannopyranose. TFP and TFLP had excellent in vivo antioxidant activity and stress resistance by regulating the mRNA transcription level and metabolites in C. elegans. Results also showed that TFP and TFLP could enhance the antioxidant capacity and immunity of serum, spleen and small intestine tissues in normal mice and cyclophosphamide-induced immunosuppressive mice through regulating the relative transcription and expression levels of anti-inflammatory related signaling factors, and it has found that TFLP showed better immune enhancement and antioxidant activity than TFP. In addition, Akkermansia, Bacteroides and Alloprevotella were characteristic bacteria at the genus level in immunosuppressed mice intervened with TFLP, with a significant increase in relative abundance. The content of SCFAs significantly increased in immunosuppressed mice by TFLP. These results indicated that TFP and TFLP had potential in vivo antioxidant and immune enhancing activities.

Micro/nano plastics in the urinary system: Pathways, mechanisms, and health risks

Micro/Nano plastics (MNPs) pollutants are widespread in the environment, raising significant concerns about their biosafety. Emerging studies indicate that the urinary system is a primary accumulation site for MNPs, leading to severe tissue and functional damage. This review aims to summarize recent research on the potential hazards that MNPs may pose to the urinary system, highlighting the mechanisms of toxicity and the current state of knowledge. Studies have shown that MNPs enter the human body through drinking water, the food chain, inhalation, and skin contact. They may penetrate the bloodstream via the digestive, respiratory, and skin systems, subsequently dispersing to various organs, including the urinary system. The potential accumulation of MNPs in the urinary system might induce cellular oxidative stress, inflammation, apoptosis, autophagy, the "intestine-kidney axis", and other possible toxic mechanisms. These processes could disrupt kidney metabolic functions and promote tissue fibrosis, thereby potentially increasing the risk of urinary system diseases. Despite ongoing research, the understanding of MNPs' impact on the urinary system remains limited. Therefore, this review provides a comprehensive overview of MNPs' potential toxicity mechanisms in the urinary system, highlights key challenges, and outlines future research directions. It offers a theoretical basis for the development of effective protective measures and policies.

Genetic Evidence for the Causal Relationship Between Gut Microbiota and Diabetic Kidney Disease: A Bidirectional, Two-Sample Mendelian Randomisation Study

Aims: According to the gut-kidney axis theory, gut microbiota (GM) has bidirectional crosstalk with the development of diabetic kidney disease (DKD). However, empirical results have been inconsistent, and the causal associations remain unclear. This study was aimed at exploring the causal relationship between GM and DKD as well as the glomerular filtration rate (GFR) and urinary albumin-to-creatinine ratio (UACR). Materials and Methods: Two-sample Mendelian randomisation (MR) analysis was performed with inverse-variance weighting as the primary method, together with four additional modes (MR-Egger regression, simple mode, weighted mode, and weighted median). We utilised summary-level genome-wide association study statistics from public databases for this MR analysis. Genetic associations with DKD were downloaded from the IEU Open GWAS project or CKDGen consortium, and associations with GM (196 taxa from five levels) were downloaded from the MiBioGen repository. Results: In forward MR analysis, we identified 13 taxa associated with DKD, most of which were duplicated in Type 2 diabetes with renal complications but not in Type 1 diabetes. We observed a causal association between genetic signature contributing to the relative abundance of Erysipelotrichaceae UCG003 and that for both DKD and GFR. Similarly, host genetic signature defining the abundance of Ruminococcaceae UCG014 was found to be simultaneously associated with DKD and UACR. In reverse MR analysis, the abundance of 14 other GM taxa was affected by DKD, including the phylum Proteobacteria, which remained significant after false discovery rate correction. Sensitivity analyses revealed no evidence of outliers, heterogeneity, or horizontal pleiotropy. Conclusion: Our findings provide compelling causal genetic evidence for the bidirectional crosstalk between specific GM taxa and DKD development, contributing valuable insights for a comprehensive understanding of the pathological mechanisms of DKD and highlighting the possibility of prevention and management of DKD by targeting GM.

Renal Health Through Medicine-Food Homology: A Comprehensive Review of Botanical Micronutrients and Their Mechanisms

BACKGROUND

As an ancient concept and practice, "food as medicine" or "medicine-food homology" is receiving more and more attention these days. It is a tradition in many regions to intake medicinal herbal food for potential health benefits to various organs and systems including the kidney. Kidney diseases usually lack targeted therapy and face irreversible loss of function, leading to dialysis dependence. As the most important organ for endogenous metabolite and exogenous nutrient excretion, the status of the kidney could be closely related to daily diet. Therefore, medicinal herbal food rich in antioxidative, anti-inflammation micronutrients are ideal supplements for kidney protection. Recent studies have also discovered its impact on the "gut-kidney" axis.

METHODS

Here, we review and highlight the kidney-protective effects of botanicals with medicine-food homology including the most frequently used Astragalus membranaceus and Angelica sinensis (Oliv.) Diels, concerning their micronutrients and mechanism, offering a basis and perspective for utilizing and exploring the key substances in medicinal herbal food to protect the kidney.

RESULTS

The index for medicine-food homology in China contains mostly botanicals while many of them are also consumed by people in other regions. Micronutrients including flavonoids, polysaccharides and others present powerful activities towards renal diseases.

CONCLUSIONS

Botanicals with medicine-food homology are widely speeded over multiple regions and incorporating these natural compounds into dietary habits or as supplements shows promising future for renal health.

Research progress of traditional Chinese medicine on the treatment of diarrhea by regulating intestinal microbiota and its metabolites based on renal-intestinal axis

Intestinal microbiota and its metabolites are involved in many physiological processes of the human body and play a vital role in maintaining human health. The occurrence of kidney disease can cause intestinal microbiota imbalance, resulting in diarrhea. The change of intestinal microbiota and its metabolites content can aggravate renal function injury, which has a bidirectional regulating effect. The theory of renal-intestinal axis further clarified that the impaired renal function is related to the imbalance of intestinal microorganisms, and the impaired intestinal barrier is related to the accumulation of toxin products. Because of its unique therapeutic advantages, Traditional Chinese Medicine can treat diarrhea by enhancing the growth of beneficial bacteria, inhibiting pathogenic bacteria and immune regulation, and slow down the continuous deterioration of kidney disease. This paper focuses on the relationship between intestinal microbiota and its metabolites and diarrhea, the influence of Traditional Chinese Medicine on intestinal microbiota in the treatment of diarrhea, and the role of intestinal microbiota and its metabolites in the renal-intestinal axis. It provides a theoretical basis for Traditional Chinese Medicine to regulate intestinal microbiota and its metabolites based on the renal-intestinal axis theory to treat nephrology-induced diarrhea, and also provides a new idea and method for Traitional Chinese Medicine to treat nephrology-induced diarrhea.

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.

A graminan type fructan from Achyranthes bidentata prevents the kidney injury in diabetic mice by regulating gut microbiota

Diabetic kidney disease (DKD) is the main cause of end-stage renal disease, and few therapeutic options are available. The root of Achyranthis bidentatae (AB) is commonly used for DKD treatment in Traditional Chinese medicine. However, its mechanisms are still unclear. Here, a graminan type fructan ABPW1 with molecular weight of 3998 Da was purified from AB. It was composed of β-1,2-linked Fruf, β-2,6-linked-Fruf and β-1,2,6-linked-Fruf backbone, and terminated with T-Glcp and 2-Fruf residues. ABPW1 protected against kidney injuries and intestinal barrier disruption in Streptozotocin (STZ)/High fat diet (HFD) mice. It could modulate gut microbiota composition, evidenced by a rise in the abundance of Bacteroide and decreases of Rikenella, Alistipes, Laedolimicola and Faecalibaculum. ABPW1 intervention promoted short chain fatty acids (SCFAs) production in STZ/HFD mice, especially propionate and isobutyric acid. Antibiotic treatment further demonstrated the key role of gut microbiota in the renal protective action of ABPW1. In addition, in vitro simulated digestion and fermentation together with in vivo fluorescent labeling studies demonstrated ABPW1 was indigestible in upper digestive tract but could reach the colon and be degraded into SCFAs by gut microbiota there. Overall, these data suggested ABPW1 has the potential application on DKD prevention.

Comparisons of procyanidins with different low polymerization degrees on prevention of lipid metabolism in high-fat diet/streptozotocin-induced diabetic mice

Procyanidins, which are oligomerized flavan-3-ols with a polyphenolic structure, are bioactive substances that exhibit various biological effects. However, the relationship between the degree of polymerization (DP) of procyanidins and their bioactivities remains largely unknown. In this study, the preventive effects of procyanidins with different DP (EC, PB2 and PC1) on glucose improvement and liver lipid deposition were investigated using a high-fat diet/streptozotocin-induced diabetes mouse model. The results demonstrated that all the procyanidins with different DP effectively reduced fasting blood glucose and glucose/insulin tolerance, decreased the lipid profile (total cholesterol, triglyceride, and low-density lipoprotein cholesterol content) in serum and liver tissue as well as the liver oil red staining, indicating the improvement of glucose metabolism, insulin sensitivity and hepatic lipid deposition in diabetic mice. Furthermore, the procyanidins down-regulated expression of glucose regulated 78-kDa protein (GRP78) and C/EBP homologous protein (CHOP), indicating a regulation role of endoplasmic reticulum (ER) stress. The inhibition of ER stress by tauroursodeoxycholic acid (TUDCA) treatment abolished the effects of procyanidins with different DP in PA-induced HepG2 cells, confirming that procyanidins alleviate liver hyperlipidemia through the modulation of ER stress. Molecular docking results showed that EC and PB2 could better bind GRP78 and CHOP. Collectively, our study reveals that the structure of procyanidins, particularly DP, is not directly correlated with the improvement of blood glucose and lipid deposition, while highlighting the important role of ER stress in the bioactivities of procyanidins.

"Qi Nan" agarwood restores podocyte autophagy in diabetic kidney disease by targeting EGFR signaling pathway

BACKGROUND

Diabetic kidney disease (DKD) is a microvascular complication of diabetes mellitus, contributing to end-stage renal disease with limited treatment options. The development of DKD is attributed to podocyte injury resulting from abnormal podocyte autophagy. Consequently, the restoration of podocyte autophagy is deemed a practicable approach in the treatment of DKD.

METHODS

Diabetic mice were induced by streptozotocin and high-fat diet feeding. Following 8 weeks of "QN" agarwood treatment, metrics such as albuminuria, serum creatinine (Scr), and blood urea nitrogen (BUN) were evaluated. Renal histological lesions were evaluated by H&E, PAS, Masson, and Sirius red staining. Evaluation of the effects of "QN" agarwood on renal inflammation and fibrosis in DKD mice through WB, q-PCR, and IHC staining analysis. Cytoscape 3.7.1 was used to construct a PPI network. With the DAVID server, the gene ontology (GO) functional annotation and the Kyoto encyclopedia of genes and genomes (KEGG) signaling pathways of the target enrichment were performed. Molecular docking and binding affinity calculations were conducted using AutoDock, while PyMOL software was employed for visualizing the docking results of active compounds and protein targets.

RESULTS

The results of this study show that "QN" agarwood reduced albuminuria, Scr, and BUN in DKD mice, and improved the renal pathological process. Additionally, "QN" agarwood was observed to downregulate the mRNA and protein expression levels of pro-inflammatory and pro-fibrotic factors in the kidneys of DKD mice. Network pharmacology predicts that "QN" agarwood modulates the epidermal growth factor receptor (EGFR) signaling pathway. "QN" agarwood can increase the expression of LC3B and Nphs1 in DKD mice while reducing the expression of EGFR.

CONCLUSION

The present study demonstrated that "QN" agarwood ameliorated renal injury in DKD by targeting EGFR and restoring podocyte autophagy.

Tangshen Formula alleviates inflammatory injury against aged diabetic kidney disease through modulating gut microbiota composition and related amino acid metabolism

Diabetic kidney disease (DKD) is leading causes and one of the fastest growing causes of chronic kidney disease worldwide, and leads to high morbidity and mortality. Emerging evidences have revealed gut microbiota dysbiosis and related metabolism dysfunction play a dominant role in DKD progression and treatment through modulating inflammation. Our previous studies showed that Tangshen Formula (TSF), a Chinese herbal prescription, exhibited anti-inflammatory effect on DKD, but underlying mechanism that involved gut microbiota and related metabolism in aged model remained obscure. Here, BTBR ob/ob mice were used to establish aged DKD model, and 16S rRNA sequence and untargeted metabolomic analyses were employed to investigate the correlation between colonic microbiota and serum metabolism. The aged ob/ob mice exhibited obvious glomerular and renal tubule injury and kidney function decline in kidney, while TSF treatment significantly attenuated these abnormalities. TSF also exhibited potent anti-inflammatory effect in aged ob/ob mice indicating by reduced proinflammatory factor IL-6 and TNF-α, MCP-1 and COX-2 in serum, kidney and intestine, which suggested the involvement of gut microbiota with TSF effect. The 16S rDNA sequencing of the colonic microbiome and untargeted serum metabolomics analysis revealed significant differences in gut microbiota structure and serum metabolomic profiles between WT and ob/ob mice. Notably, TSF treatment reshaped the structure of gut microbiota and corrected the disorder of metabolism especially tryptophan metabolism and arginine biosynthesis. TSF increased Anaeroplasma and Barnesiella genera and decreased Romboutsia, Akkermansia, and Collinsella genera, and further elevated tryptophan, 5-hydroxyindoleacetate, glutamic acid, aspartate and reduced 4-hydroxy-2-quinolinecarboxylic acid, indole-3-acetic acid, xanthurenic acid, glutamine. Further correlation analysis indicated that disturbed gut microbiota was linked to tryptophan metabolism and arginine biosynthesis to regulate inflammation in aged DKD. Our data revealed that TSF attenuated renal inflammation by modulating gut microbiota and related amino acid metabolism in aged DKD model, highlighting gut microbiota and related metabolism functioned as potential therapeutic target for DKD in elderly patients.

Abscisic acid ameliorates d-galactose -induced aging in mice by modulating AMPK-SIRT1-p53 pathway and intestinal flora

Abscisic acid (ABA) is a plant hormone with various biological activities. Aging is a natural process accompanied by cognitive and physiological decline, and aging and its associated diseases pose a serious threat to public health, but its mechanisms remain insufficient. Therefore, the purpose of this study was to investigate the ameliorative effects of ABA on d-galactose (D-Gal)-induced aging in mice and to delve into its molecular mechanisms. Aging model was es-tablished by theintraperitoneal injection of D-Gal. We evaluated the oxidative stress by measuring superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT) levels in serum. Proteins content in brain were determined by Western blot. D-Gal-induced brain damage was monitored by measuring the levels of acetylcholinesterase (AChE) content and hematoxylin-eosin staining (H&E). To evaluate the effects of ABA on aging, we measured the gut microbiota. The results demonstrated that ABA increased SOD, CAT and AChE, decreased MDA level. H&E staining showed that ABA could improve D-Gal-induced damage. In addition, ABA regulated the B-cell-lymphoma-2 (BCL-2) family and Phosphatidylinositol 3-kinase/Protein kinase B (PI3K/AKT) signaling pathway, while further regulating the acetylation of p53 protein by modulating the AMPK pathway and activating SIRT1 protein, thereby inhibiting the apoptosis of brain neurons and thus regulating the aging process. Interestingly, ABA improved the ratio of intestinal bacteria involved in regulating multiple metabolic pathways in the aging process, such as Bacteroides, Firmicutes, Lactobacillus and Ak-kermansia. In conclusion, the present study suggests that ABA may be responsible for improving and delaying the aging process by enhancing antioxidant activity, anti-apoptosis and regulating intestinal flora.

Association between gut microbiota and diabetic nephropathy: a mendelian randomization study

Background

The correlation between diabetic nephropathy (DN) and gut microbiota (GM) has been suggested in numerous animal experiments and cross-sectional studies. However, a causal association between GM and DN has not been ascertained.

Methods

This research adopted MR analysis to evaluate the causal link between GM and DN derived from data acquired through publicly available genome-wide association studies (GWAS). The study utilized the inverse variance weighted (IVW) approach to assess causal association between GM and DN. Four additional methods including MR-Egger, weighted median, weighted mode, and simple mode were employed to ensure comprehensive analysis and robust results. The Cochran's Q test and the MR-Egger method were conducted to identify heterogeneity and horizontal pleiotropy, respectively. The leave-one-out approach was utilized to evaluate the stability of MR results. Finally, a reverse MR was performed to identify the reverse causal association between GM and DN.

Results

According to IVW analysis, Class Verrucomicrobiae (p = 0.003), Order Verrucomicrobiales (p = 0.003), Family Verrucomicrobiaceae (p = 0.003), Genus Akkermansia (p = 0.003), Genus Catenibacterium (p = 0.031), Genus Coprococcus 1 (p = 0.022), Genus Eubacterium hallii group (p = 0.018), and Genus Marvinbryantia (p = 0.023) were associated with a higher risk of DN. On the contrary, Class Actinobacteria (p = 0.037), Group Eubacterium ventriosum group (p = 0.030), Group Ruminococcus gauvreauii group (p = 0.048), Order Lactobacillales (p = 0.045), Phylum Proteobacteria (p = 0.017) were associated with a lower risk of DN. The sensitivity analysis did not identify any substantial pleiotropy or heterogeneity in the outcomes. We found causal effects of DN on 11 GM species in the reverse MR analysis. Notably, Phylum Proteobacteria and DN are mutually causalities.

Conclusion

This study identified the causal association between GM and DN with MR analysis, which may enhance the understanding of the intestinal-renal axis and provide novel potential targets for early non-invasive diagnosis and treatment of DN.

Anti-diabetic effect of red quinoa polysaccharide on type 2 diabetic mellitus mice induced by streptozotocin and high-fat diet

The purpose of this study was to explore the mechanism of red quinoa polysaccharide (RQP) in alleviating type 2 diabetes (T2D) through in vivo and in vitro experiments. Results of HPLC and FITR showed that RQP was a complex polysaccharide and contained more glucose, galactose and acarbose. In vitro experiments, RQP showed strong antioxidant capacity and inhibition on α-amylase and α-glucosidase. In vivo experiments, RQP was proved to induce a significant improvement of diabetes after 4 weeks of ingestion, including the abilities of lowering blood glucose, regulating lipid metabolism, anti-oxidation and promoting secretion of SCFAs. Furthermore, 16S rRNA study demonstrated that RQP transformed the intestinal microbiota composition in diabetic mice, decreased the abundance of norank_f_Muribaculaceae and Lachnospiraceae_NK4A136_group, and increased the relative abundance of Akkermansia, unclassified_f_Lachnospiraceae, norank_f_Eubacterium_coprostanoligenes_group, unclassified_f_Atopobiaceae and norank_f_Lachnospiraceae. The biosynthetic pathways, metabolic pathways and intestinal microbiome phenotypes in mice also changed accordingly. In conclusion, this study suggests that RQP can inhibit the development of diabetes by correcting the imbalance of intestinal flora.

Metagenomic sequencing revealed the regulative effect of Danshen and Honghua herb pair on the gut microbiota in rats with myocardial ischemia injury

In recent years, more and more evidence has shown that the disorder of gut microbiota (GM) is closely correlated with myocardial ischemia (MI). Even though the Danshen and Honghua herb pair (DHHP) is widely used in treating cardiovascular disease in China and exhibits obvious clinical efficacy on MI, the anti-MI mechanism of DHHP remains and needs to be explored in depth. Thus, in this study, we investigated whether the amelioration effect and molecular mechanism of DHHP on MI were related to regulating GM through pharmacodynamics evaluation and metagenomic sequencing. Histopathological testing results showed that DHHP treatment could alleviate the pathological changes of myocardial tissue in the acute MI (AMI) rats induced by isoproterenol (ISO), especially structural disorder, irregular distribution, and enlargement of the myocardial space. These pathological changes were all alleviated to some extent by DHHP treatment. Biochemical analysis results suggested that compared with the control group, the serum levels of AST, CTn-I, CK-MB, and TNF-α in model group rats were notably decreased, and the CAT and SOD levels in serum were markedly increased. These abnormal trends were significantly reversed by DHHP treatment. Furthermore, metagenomic sequencing analysis results indicated that DHHP could improve disorders in the composition and function of GM in AMI rats, mainly reflected in increasing diversity and richness, and obviously enhancing the abundance of Bacteroides fluxus, B. uniformis, B. stercoris, Roseburia hominis, Schaedlerella arabinosiphila, and R. intestinalis, and reducing the abundance of Enterococcus avium and E. canintestini, which were associated with purine metabolism, tyrosine metabolism, cyanoamino acid metabolism, and glutathione metabolism. In conclusion, DHHP may attenuate ISO-induced MI by regulating the structure, composition, and function of GM, thus contributing to further our understanding of the anti-MI mechanisms of DHHP and providing new therapeutic ideas and diagnostic targets for the clinical studies of MI.

Exploring global research status and trends in anti-obesity effects of traditional Chinese medicine through intestinal microbiota: a bibliometric study

Background

The intestinal microbiota (IM) has been found to contribute to metabolic disorders that lead to excessive fat accumulation, systemic and chronic low-grade inflammation, and insulin resistance in the host. Current research highlights a pivotal interaction between IM and traditional Chinese medicine (TCM) in mitigating obesity-related diseases. Undeniably, IM stands as a central focus in TCM research aimed at preventing and treating obesity. Therefore, tracing the progress and trends in this field can offer valuable references and insights for future studies.

Methods

On June 17, 2023, we conducted a literature search on the topic of "IM and obesity in TCM" spanning the period from 2009 to 2023. We extracted the primary information of the publications, which includes complete records and reference citations, from the Science Citation Index Expanded (SCI-E) within the Web of Science Core Collection (WoSCC). To visualize and analyze the literature, we utilized CiteSpace and VOSviewer for bibliometric analysis.

Results

During the past fifteen years, a rapid increase in the number of publications has been observed. The cooperative networks demonstrate China, Beijing University of Chinese Medicine, and Food & Function as the most active countries, organizations, and journals in this field, respectively. Liu Bin has contributed the most publications. A paper by Xu Jia, published in 2014, holds the highest Local Citation Score (LCS). Analyses of keyword co-occurrence and reference co-citation indicate that the research hotspots of IM and obesity in TCM are primarily focused on the metabolic benefits driven by endogenous functional metabolic molecules generated by TCM regulation of IM. Other focal points include the mechanism by which TCM regulates IM to restore the intestinal mucosal barrier This is a provisional file, not the final typeset article, and manages the gut-organ axis, the metabolic advantages of acupuncture's regulation of IM, and the process by which Chinese medicine small molecules transform IM.

Conclusion

This research offers a comprehensive understanding of the current status, hotspots, and trends in global TCM research. Additionally, it provides a comprehensive summary and exploration of the latest advancements in this field, thereby emphasizing the essence of TCM more effectively.