Psyllium seed husk regulates the gut microbiota and improves mucosal barrier injury in the colon to attenuate renal injury in 5/6 nephrectomy rats.

Chronic kidney disease (CKD) can cause gut microbiota dysbiosis and thus impair intestinal barrier function. Disruption of intestinal homeostasis facilitates the production of enterogenic toxins, which exacerbate CKD-induced uremic toxicity and inflammation. Dietary fiber, by targeting the gut-kidney axis, could be used for CKD treatment. Psyllium seed husk (PSH) extracted from the seeds of Plantago ovata contains highly branched, gel-forming arabinoxylan. Positive effects of PSH on host physiology have been demonstrated but whether it also acts on the microbial ecosystem in CKD patients is unknown. In this study, the effects of dietary PSH on the gut microbiota, intestinal barrier function, systemic inflammation, uremic toxins, and renal injury were investigated in 5/6 nephrectomy (5/6Nx) CKD rats. Blood, feces, and kidney and colon tissues were collected from PSH-treated and control rats and subjected to biochemical and histological analyses, enzyme-linked immunosorbent assays, and 16SrRNA sequencing. PSH supplementation reduced serum creatinine and blood urea nitrogen levels, and attenuated renal tubular interstitial injury, in 5/6Nx rats. 16SrRNA sequencing showed that PSH improved the gut microbiota and intestinal barrier function in addition to down-regulating serum interleukin (IL)-1, IL-6, and indoxyl sulfate levels. Together, these results demonstrate the potential of PSH supplementation for treating CKD, including by improving intestinal microecology, reducing uremic toxin levels and systemic inflammation, and delaying disease progression.

A Fast Linearly Wavelength Step-Swept Light Source Based on Recirculating Frequency Shifter and Its Application to FBG Sensor Interrogation.

A wavelength step-swept light source (WSSL) using a recirculating frequency shifter loop (RFSL) based on a single-side-band (SSB) modulator is proposed, in order to achieve a linear and fast wavelength-sweeping. The swept step can be tuned from 1.2 pm to 128 pm by adjusting a precise and stable radio frequency (RF) signal that is applied to the SSB modulator. The swept rate can be tuned up to 99 kHz in a range of over 5.12 nm. Wavelength-to-time mapping is used to measure static strain-induced or temperature-induced shifting of the reflected central wavelength of a fiber Bragg grating (FBG). Because of the high linearity of the light source, the interrogation linearity of the strain and the temperature are as high as 0.99944 and 0.99946, respectively. When a dynamic periodic strain applied to FBG sensor, the dynamic performance of the FBG sensor is successfully recorded in the time domain and its power spectral density of a fast Fourier transform (FFT) is calculated. The signal-to-noise ratio (SNR) of the power spectral density is over 40 dB for a 100 Hz dynamic strain and the calculated sensitivity is 0.048 µÎµ/Hz1/2. A sharp change in the strain frequency from 100 Hz to 500 Hz is captured in real time.

Broadband linearly chirped light source with narrow linewidth based on external modulation.

An external modulation method is proposed and experimentally demonstrated for the generation of linearly chirped light over broadband with narrow linewidth. Our chirped light source is a combination of an optical recirculating frequency shifter loop and an optical frequency linear sweeper. A linearly chirped light over a range of 200 GHz at a chirp rate of 3.6×1016 Hz/s is generated. The instantaneous linewidth of the chirped light is estimated to be less than 50 kHz.

Grape seed proanthocyanidin extract protects human umbilical vein endothelial cells from indoxyl sulfate-induced injury via ameliorating mitochondrial dysfunction.

OBJECTIVE: To investigate the effects of grape seed proanthocyanidin extract (GSPE) on indoxyl sulfate-induced Human Umbilical Vein Endothelial Cells (HUVECs) injury in vitro and study its mechanism. METHODS: HUVECs were incubated with indoxyl sulfate at concentrations in the range found in uremic patients. Then we determined the effect of indoxyl sulfate on endothelial phenotype, endothelial function, ROS (reactive oxygen species), cell apoptosis and mitochondrial function. In addition, we detected whether GSPE can suppress the injury of HUVECs induced by indoxyl sulfate and probe the mechanism underlying the protective effects of GSPE by analyzing mitochondrial dysfunction. RESULTS: GSPE treatment significantly attenuated indoxyl sulfate-induced HVUECs injury in a dose- and time-dependent manner. GSPE-enhanced eNOS and VE-cadherin expression, inhibited intracellular ROS level and cell apoptosis, adjust mitochondrial membrane potential and reduced 8-hydroxy-desoxyguanosine (8-OHdG) level induced by indoxyl sulfate. CONCLUSION: These results suggest that GSPE prevents HUVECs from indoxyl sulfate-induced injury by ameliorating mitochondrial dysfunction and may be a promising agent for treating uremia toxin-induced injury.

Rationale and design of the Helping Ease Renal failure with Bupi Yishen compared with the Angiotensin II Antagonist Losartan (HERBAAL) trial: a randomized controlled trial in non-diabetes stage 4 chronic kidney disease.

BACKGROUND: Chronic kidney disease (CKD) is a global public health problem. Currently, as for advanced CKD populations, medication options limited in angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARB), which were partially effective. A Chinese herbal compound, Bupi Yishen formula, has showed renal protective potential in experiments and retrospective studies. This study will evaluate the efficacy and safety of Bupi Yishen formula (BYF) in patients with CKD stage 4. DESIGN: In this double blind, double dummy, randomized controlled trial (RCT), there will be 554 non-diabetes stage 4 CKD patients from 16 hospitals included and randomized into two groups: Chinese medicine (CM) group or losartan group. All patients will receive basic conventional therapy. Patients in CM group will be treated with BYF daily while patients in control group will receive losartan 100 mg daily for one year. The primary outcome is the change in estimated glomerular filtration rate (eGFR) over 12 months. Secondary outcomes include the incidence of endpoint events, liver and kidney function, urinary protein creatinine ratio, cardiovascular function and quality of life. DISCUSSION: This study will be the first multi-center, double blind RCT to assess whether BYF, compared with losartan, will have beneficial effects on eGFR for non-diabetes stage 4 CKD patients. The results will help to provide evidence-based recommendations for clinicians. TRIAL REGISTRATION: Chinese Clinical Trial Registry Number: ChiCTR-TRC-10001518 .

Integrins as a bridge between bacteria and cells: key targets for therapeutic wound healing.

Integrins are heterodimers composed of α and ß subunits that are bonded through non-covalent interactions. Integrins mediate the dynamic connection between extracellular adhesion molecules and the intracellular actin cytoskeleton. Integrins are present in various tissues and organs where these heterodimers participate in diverse physiological and pathological responses at the molecular level in living organisms. Wound healing is a crucial process in the recovery from traumatic diseases and comprises three overlapping phases: inflammation, proliferation and remodeling. Integrins are regulated during the entire wound healing process to enhance processes such as inflammation, angiogenesis and re-epithelialization. Prolonged inflammation may result in failure of wound healing, leading to conditions such as chronic wounds. Bacterial colonization of a wound is one of the primary causes of chronic wounds. Integrins facilitate the infectious effects of bacteria on the host organism, leading to chronic inflammation, bacterial colonization, and ultimately, the failure of wound healing. The present study investigated the role of integrins as bridges for bacteria-cell interactions during wound healing, evaluated the role of integrins as nodes for bacterial inhibition during chronic wound formation, and discussed the challenges and prospects of using integrins as therapeutic targets in wound healing.

Integrins regulation of wound healing processes: insights for chronic skin wound therapeutics.

Integrins are heterodimers composed of non-covalently associated alpha and beta subunits that mediate the dynamic linkage between extracellular adhesion molecules and the intracellular actin cytoskeleton. Integrins are present in various tissues and organs and are involved in different physiological and pathological molecular responses in vivo. Wound healing is an important process in the recovery from traumatic diseases and consists of three overlapping phases: inflammation, proliferation, and remodeling. Integrin regulation acts throughout the wound healing process to promote wound healing. Prolonged inflammation may lead to failure of wound healing, such as wound chronicity. One of the main causes of chronic wound formation is bacterial colonization of the wound. In this review, we review the role of integrins in the regulation of wound healing processes such as angiogenesis and re-epithelialization, as well as the role of integrins in mediating bacterial infections during wound chronicity, and the challenges and prospects of integrins as therapeutic targets for infected wound healing.

Role and research progress of spasmolytic polypeptide­expressing metaplasia in gastric cancer (Review).

Gastric cancer ranks as one of the most prevalent cancers worldwide. While the incidence of gastric cancer in Western countries has notably diminished over the past century, it continues to be a leading cause of cancer­related mortality on a global scale. The majority of gastric cancers in humans are attributed to chronic Helicobacter pylori infection and the progression of gastric cancer is often preceded by gastritis, atrophy, metaplasia and dysplasia. However, the precise mechanisms underlying the development of gastric cancer remain ambiguous, including the formation of gastric polyps and precancerous lesions. In humans, two types of precancerous metaplasia have been identified in relation to gastric malignancies: Intestinal metaplasia and spasmolytic polypeptide­expressing metaplasia (SPEM). The role of SPEM in the induction of gastric cancer has gained recent attention and its link with early­stage human gastric cancer is increasingly evident. To gain insight into SPEM, the present study reviewed the role and research progress of SPEM in gastric cancer.

Sanqi oral solution ameliorates renal fibrosis by suppressing fibroblast activation via HIF-1α/PKM2/glycolysis pathway in chronic kidney disease.

ETHNOPHARMACOLOGICAL RELEVANCE: Sanqi oral solution (SQ) is a traditional Chinese patent medicine, widely used to treat chronic kidney diseases (CKD) in the clinic in China. Previous studies have confirmed its anti-renal fibrosis effect, but the specific pharmacological mechanism is still unclear. AIM OF THE STUDY: Focusing on energy metabolism in fibroblasts, the renoprotective mechanism of SQ was investigated in vitro and in vivo. METHODS: Firstly, the fingerprint of SQ was constructed and its elementary chemical composition was analyzed. In the 5/6Nx rats experiment, the efficacy of SQ on the kidney was evaluated by detecting serum and urine biochemical indexes and pathological staining of renal tissues. Lactic acid and pyruvic acid levels in serum and renal tissues were detected. PCNA protein expression in kidney tissue was detected by immunofluorescence assay and Western blot. Expression levels of HIF-1α, PKM2 and HK2 were determined by immunohistochemistry, Western blot or RT-qPCR assay. In addition, the effect of SQ intervention on cell proliferation and glycolysis was evaluated in TGF-ß1-induced NRK-49F cells, and the role of SQ exposure and HIF-1α/PKM2/glycolysis pathway were further investigated by silencing and overexpressing HIF-1α gene in NRK-49F cells. RESULTS: In 5/6 Nx rats, SQ effectively improved renal function and treated renal injury. It reduced the levels of lactic acid and pyruvic acid in kidney homogenates from CKD rats and decreased the expression levels of HIF-1α, PKM2, HK2, α-SMA, vimentin, collagen I and PCNA in kidney tissues. Similar results were observed in vitro. SQ inhibited NRK-49F cell proliferation, glycolysis and the expression levels of HIF-1α, PKM2 induced by TGF-ß1. Furthermore, we established NRK-49F cells transfected with siRNA or pDNA to silence or overexpress the HIF-1α gene. Overexpression of HIF-1α promoted cellular secretion of lactic acid and pyruvic acid in TGF-ß1-induced NRK-49F cells, however, this change was reversed by intervention with SQ or silencing the HIF-1α gene. Overexpression of HIF-1α can further induce increased PKM2 expression, while SQ intervention can reduce PKM2 expression. Moreover, PKM2 expression was also inhibited after silencing HIF-1α gene, and SQ was not effective even when given. CONCLUSION: The mechanism of action of SQ was explored from the perspective of energy metabolism, and it was found to regulate PKM2-activated glycolysis, inhibit fibroblast activation, and further ameliorate renal fibrosis in CKD by targeting HIF-1α.

Myeloid sarcoma with maxillary gingival swelling as the initial symptom: A case report and review of literature.

BACKGROUND: Myeloid sarcoma (MS), also referred to as granulocytic sarcoma or chloroma, is a rare type of extramedullary malignant tumor. MS comprises primitive granulocytic precursor cells that play a key role in the early stages of white blood cell development. Notably, the occurrence of this tumor in the gingiva is rare. CASE SUMMARY: The present study reported the case of MS with gingival swelling in the maxillary region, with aleukemic presentation in a 32-year-old male patient. Following two courses of chemotherapy, computed tomography of the region demonstrated complete clearance of the tumor. At the 12-month follow-up appointment, the patient was in a stable condition with the absence of progression. The etiology, clinical features, diagnosis, and relevant treatment of MS are discussed in the present study. CONCLUSION: Diagnosis of MS may be confirmed following histological and immunohistochemical examinations.

Preparation of Luvangetin Nanoemulsions: Antimicrobial Mechanism and Role in Infected Wound Healing.

Purpose: Incorporation of luvangetin in nanoemulsions for antimicrobial and therapeutic use in infected wound healing. Patients and Methods: Luvangetin nanoemulsions were prepared by high-speed shear method and characterized based on their appearance structure, average droplet size, polydispersity index (PDI), electric potential, storage stability. Optimized formulation of luvangetin nanoemulsion by Box-Behnken design (BBD). The antimicrobial activity and antimicrobial mechanism of luvangetin nanoemulsions against common hospital pathogens, ie, Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), were investigated using luvangetin nanoemulsions. The biosafety of luvangetin nanoemulsion was evaluated through cytotoxicity, apoptosis, and reactive oxygen species (ROS) assay experiments using human normal epidermal cells and endothelial cells. Finally, the effect of luvangetin nanoemulsion on healing of infected wounds was investigated in B6 mice. Results: Luvangetin nanoemulsion formulation consists of 2.5% sunflower seed oil, 10% emulsifier Span-20 and 7 minutes of shear time, and with good stability. Luvangetin nanoemulsion produces antibacterial activity against S. aureus and E. coli by disrupting the structure of bacterial cell membranes. Luvangetin nanoemulsion are biologically safe for HaCat and HUVEC. Luvangetin nanoemulsion showed good therapeutic effect on MRSA infected wounds in mice. Conclusion: For the first time, developed a new formulation called luvangetin nanoemulsion, which exhibited superior antibacterial effects against Gram-positive bacteria. Luvangetin nanoemulsion has a favorable effect in promoting infected wound healing. We have combined luvangetin, which has multiple activities, with nanoemulsions to provide a new topical fungicidal formulation, and have comprehensively evaluated its effectiveness and safety, opening up new possibilities for further applications of luvangetin.

Ultrabright Dibenzofluoran-Based Polymer Dots with NIR-IIa Emission Maxima and Unusual Large Stokes Shifts for 3D Rotational Stereo Imaging.

Emerging organic molecules with emissions in the second near-infrared (NIR-II) region are garnering significant attention. Unfortunately, achieving accountable organic emission intensity over the NIR-IIa (1300 nm) region faces challenges due to the intrinsic energy gap law. Up to the current stage, all reported organic NIR-IIa emitters belong to polymethine-based dyes with small Stokes shifts (<50 nm) and low quantum yield (QY; ≤0.015%). However, such polymethines have proved to cause self-absorption with constrained emission brightness, limiting advanced development in deep-tissue imaging. Here a new NIR-IIa scaffold based on rigid and highly conjugated dibenzofluoran core terminated by amino-containing moieties that reveal emission peaks of 1230-1305 nm is designed. The QY is at least 10 times higher than all synthesized or reported NIR-IIa polymethines with extraordinarily large Stokes shifts of 370-446 nm. DBF-BJ is further prepared as a polymer dot to demonstrate its in vivo 3D stereo imaging of mouse vasculature with a 1400 nm long-pass filter.

Iron Nanoparticles Open Up New Directions for Promoting Healing in Chronic Wounds in the Context of Bacterial Infection.

Metal nanoparticles play an outstanding role in the field of wound healing due to their excellent properties, and the significance of iron, one of the most widely used metals globally, cannot be overlooked. The purpose of this review is to determine the importance of iron nanoparticles in wound-healing dressings. Prolonged, poorly healing wounds may induce infections; wound infections are a major cause of chronic wound formation. The primary components of iron nanoparticles are iron oxide nanoparticles, which promote wound healing by being antibacterial, releasing metal ions, and overcoming bacterial resistance. The diameter of iron oxide nanoparticles typically ranges between 1 and 100 nm. Magnetic nanoparticles with a diameter of less than 30 nm are superparamagnetic and are referred to as superparamagnetic iron oxide nanoparticles. This subset of iron oxide nanoparticles can use an external magnetic field for novel functions such as magnetization and functionalization. Iron nanoparticles can serve clinical purposes not only to enhance wound healing through the aforementioned means but also to ameliorate anemia and glucose irregularities, capitalizing on iron's properties. Iron nanoparticles positively impact the healing process of chronic wounds, potentially extending beyond wound management.

Tryptophan intake, not always the more the better.

Objectives: To investigate the effects of excessive tryptophan intake on the body and the effects of tryptophan metabolism-related aryl hydrocarbon receptor (AhR) pathway in healthy rats and chronic kidney disease rats, to study the adverse effects of excess tryptophan. Design: In Part I Experiment, the healthy rats were fed with diet containing 0.6, 1.2 and 1.8% tryptophan for 12 weeks. After the intervention, the blood and kidney tissues were collected. Serum creatinine and blood urea nitrogen were detected. Hematoxylin-eosin (H&E) staining was used to observe renal pathological changes. Enzyme-linked immunosorbent assay was used to detect serum kynurenic acid and AhR levels. The kidney levels of AhR, CyP1A1 and CyP1B1 were detected by western-blot. In Part II Experiment, the chronic kidney disease (CKD) model was induced by intra-gastric gavage with adenine for 4 weeks. Then the CKD rats were given tryptophan at a dose of 100 mg/kg or 500 mg/kg for eight weeks. Rat survival curve, renal function, renal tissue pathology and serum AhR were detected. Tryptophan-targeted ultra-high-performance liquid chromatography coupled with multiple reaction monitoring mass spectrometry (UHPLC-MRM-MS) was employed to quantitatively access the tryptophan-targeted metabolites in two parts experiments. Results: In part I experiment, high tryptophan diet can increase the level of blood urea nitrogen (BUN) in healthy rats and induce focal renal tubulointerstitial injury. Tryptophan-targeted analyzes showed that high tryptophan diet feeding can significantly increase the concentration of kynurenine and indole metabolites. The serum AhR level and kidney AhR, CyP1A1 and CyP1B1 were also significantly increased in high tryptophan diet rats. In part II experiment, high tryptophan intervention induced a significant increase in mortality, serum creatinine, urea nitrogen levels, and renal pathological damage in CKD rats. The levels of tryptophan-targeted metabolites, kynurenine, xanthurenate, picolinic acid, 5-hydroxyindole-3-acetic acid, indole-3-lactic acid, indoleacetate and indoxyl sulfate, showed an upward trend in the high-dose tryptophan group (Ade + Trp-H) compared with the adenine group. The serum AhR of Ade + Trp-H rats was significantly higher than those of adenine rats. Conclusion: Moderate tryptophan intake may be beneficial, but excessive tryptophan can lead to accumulation of kynurenine and indole metabolites, activate AhR pathway and induce kidney injury.

Astragaloside IV attenuates indoxyl sulfate-induced injury of renal tubular epithelial cells by inhibiting the aryl hydrocarbon receptor pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Astragalus membranaceus Fisch. ex Bunge has long been used to treat chronic kidney disease (CKD) in China. However, the mechanism of action requires further study. Indoxyl sulfate accumulation is the key cause of CKD progression. The aryl hydrocarbon receptor (AhR) plays an essential role in the renal tubular injury induced by indoxyl sulfate (IS). AIM: We explored the effects of Astragaloside IV (AS-IV), a minor component of the flowering perennial Astragalus membranaceus Fisch. ex Bunge, on AhR activity during IS-induced injury of renal tubular epithelial cells. METHODS: C57BL/6 mice fed a 0.2% adenine diet (adenine + IS) and intraperitoneally injected with IS were used to study the protective effects of AS-IV, and specifically the effect on the AhR. In addition, apoptosis (annexin/PI), oxidative stress and the AhR pathway were investigated in IS-stimulated HK-2 cells treated with AS-IV. The binding of AS-IV to the AhR was assessed in a molecular docking analysis. AhR knockdown using AhR siRNA allowed determination of the effects of AS-IV in IS-stimulated HK-2 cells. RESULTS: AS-IV inhibited tubulointerstitial injury in adenine + IS mice. While AS-IV did not reduce serum IS levels, it did inhibit AhR expression in the kidney. In IS-stimulated HK-2 cells, AS-IV also dramatically reduced apoptosis, decreased oxidative stress responses and inhibited the expression of the AhR pathway. The molecular docking analysis showed surface binding of AS-IV to the AhR. Following AhR knockdown in HK-2 cells, IS-induced apoptosis was reduced and could not be further reduced by AS-IV. CONCLUSION: By targeting the AhR, AS-IV may alleviate IS-induced renal tubular injury, thus offering a novel therapeutic approach to the treatment of chronic renal failure.

Current status and progress in research on dressing management for diabetic foot ulcer.

Diabetic foot ulcer (DFU) is a major complication of diabetes and is associated with a high risk of lower limb amputation and mortality. During their lifetime, 19%-34% of patients with diabetes can develop DFU. It is estimated that 61% of DFU become infected and 15% of those with DFU require amputation. Furthermore, developing a DFU increases the risk of mortality by 50%-68% at 5 years, higher than some cancers. Current standard management of DFU includes surgical debridement, the use of topical dressings and wound decompression, vascular assessment, and glycemic control. Among these methods, local treatment with dressings builds a protective physical barrier, maintains a moist environment, and drains the exudate from DFU wounds. This review summarizes the development, pathophysiology, and healing mechanisms of DFU. The latest research progress and the main application of dressings in laboratory and clinical stage are also summarized. The dressings discussed in this review include traditional dressings (gauze, oil yarn, traditional Chinese medicine, and others), basic dressings (hydrogel, hydrocolloid, sponge, foam, film agents, and others), bacteriostatic dressings, composite dressings (collagen, nanomaterials, chitosan dressings, and others), bioactive dressings (scaffold dressings with stem cells, decellularized wound matrix, autologous platelet enrichment plasma, and others), and dressings that use modern technology (3D bioprinting, photothermal effects, bioelectric dressings, microneedle dressings, smart bandages, orthopedic prosthetics and regenerative medicine). The dressing management challenges and limitations are also summarized. The purpose of this review is to help readers understand the pathogenesis and healing mechanism of DFU, help physicians select dressings correctly, provide an updated overview of the potential of biomaterials and devices and their application in DFU management, and provide ideas for further exploration and development of dressings. Proper use of dressings can promote DFU healing, reduce the cost of treating DFU, and reduce patient pain.

Kaempferol attenuated diabetic nephropathy by reducing apoptosis and promoting autophagy through AMPK/mTOR pathways.

Introduction: Renal podocyte injury, apoptosis and autophagy are involved in the occurrence and development of diabetic nephropathy (DN). Kaempferol (KPF) has the promotion of autophagy and inhibition of apoptosis properties in the development of miscellaneous diseases, but these functions in DN have not yet been elucidated. Methods: We used db/db mice to evaluate the protective role of KPF on DN. The anti-DN effect of KPF was evaluated by urine albumin-to-creatinine ratio and pathological changes of kidney tissue. Injury of podocytes was observed through Transmission electron microscopy. Immunofluorescence, Western blot, and Immunohistochemistry were used to detect the protein expression of podocyte-associated molecules, autophagy, and AMPK/mTOR pathway. Results: We demonstrated that KPF treatment significantly attenuated diabetes-induced albuminuria and glycolipid metabolism dysfunction. In addition, KPF alleviated mesangial matrix expansion, glomerular basement membrane thickening and loss or fusion of podocytes. Mechanistically, KPF treatment regulated the expression of autophagic proteins (upregulated LC3II, Beclin-1, Atg7 and Atg 5, and downregulated p62/SQSTM1), accompanied by inhibited renal apoptosis (downregulated Caspase 3 and Bax, and upregulated Bcl-2). KPF could significantly regulate the AMPK/mTOR signaling pathways by increasing p-AMPK and decreasing p-mTOR expressions. Discussion: In conclusion, KPF might have a protective effect on DN through reduced apoptosis and enhanced podocytes autophagy, which were correlated with regulating AMPK/mTOR pathways.

Huaier attenuates the adverse effects of pyroptosis by regulating the methylation of rat mesangial cells: an in vitro study.

BACKGROUND: Pyroptosis is a highly programmed inflammatory cell death process that represents an innate immune response. In this study, the occurrence of pyroptosis in rat mesangial cells (RMCs) and the effect of Huaier (Trametes robiniophia Murr) on this process were investigated. METHODS: RMCs were incubated with OX7 antibodies (0.5 µg/ml, 2.5 µg/ml, 10 µg/ml), normal rat serum (NRS) and Huaier (1 mg/ml, 5 mg/ml, 10 mg/ml). RMC morphology was observed under a light microscope and by immunofluorescence. Lactate dehydrogenase (LDH) release was assessed using the CytoTox 96 Non-Radioactive Cytotoxicity Assay Kit. Western blot assays were performed, and then the RMCs were incubated with the methylase DNMT3B and the demethylase 5-aza-2'-deoxycytidine. RESULTS: Morphological, LDH, immunofluorescence and western blot analyses showed that RMCs were lysed when stimulated with OX7 antibodies and NRS. RMC lysis released inflammatory cytokines (interleukin-18, interleukin-1ß, monocyte chemoattractant protein-1 and intracellular adhesion molecule-1), and Huaier protected RMCs by controlling lysis and the levels of inflammatory cytokines. Lysis was mediated by pyroptosis due to the positive expression of GSDME. The methylase DNMT3B reduced the expression of GSDME induced by OX7 together with NRS. Furthermore, Huaier significantly suppressed the expression of GSDME, which was increased by 5-aza-2'-deoxycytidine. CONCLUSIONS: Pyroptosis might occur in RMCs, and Huaier can protect RMCs by upregulating the methylation of a group of molecules.

Rhubarb Enema Increasing Short-Chain Fatty Acids that Improves the Intestinal Barrier Disruption in CKD May Be Related to the Regulation of Gut Dysbiosis.

The incidence of CKD seriously endangers people's health. Researchers have proposed that improving the intestinal barrier damage in CKD may be an effective target for delaying the progression of CKD. Rhubarb can effectively improve the intestinal barrier and renal fibrosis, which may be related to the regulation of gut dysbiosis, but the mechanism needs to be further studied. Short-chain fatty acids (SCFAs) are important metabolites of the gut microbiota and play an important role in maintaining the intestinal barrier. The purpose of this study was to investigate whether rhubarb enema regulates the production of short-chain fatty acid-related gut microbiota and improves the intestinal barrier damage of CKD. 5/6 nephrectomy rats were used as the animal model, sevelamer was used as the positive control group, and the sham operation rats were used as the control group. After 4 weeks of enema treatment, the general clinical indicators, short-chain fatty acid levels, renal pathology, intestinal tissue pathology, intestinal tight junction protein, and changes in gut microbiota were detected. The results showed that rhubarb enema can increase the level of short-chain fatty acids in the 5/6 nephrectomy model rats, improve the intestinal barrier damage, inhibit the decrease of intestinal tight junction proteins, reduce inflammation levels, improve kidney pathology, reduce blood creatinine levels, and regulate the intestinal tract, the abundance, and composition of the flora. Further correlation analysis showed that rhubarb enema increased the level of short-chain fatty acids in 5/6 nephrectomy model rats, which may be related to the 7 strains that may regulate the production of short-chain fatty acids. This study indicated that rhubarb enema can improve the intestinal barrier damage of 5/6 nephrectomy model rats and improve CKD, which may be related to the regulation of short-chain fatty acid-producing gut microbiota.

Effect of 5/6 nephrectomized rat serum on epithelial-to-mesenchymal transition in vitro.

OBJECTIVE: To investigate whether the 5/6 nephrectomized (5/6Nx) rats' 12-week serum could lead to tubular epithelial-to-mesenchymal transition (EMT) and its molecular mechanism, so as to probe the potential stimulation from circulation in chronic progressive kidney disease. METHODS: A total of 24 Sprague Dawley (SD) rats were randomly divided into two groups: sham operation group (sham group) and 5/6Nx group. Rats were killed 12 weeks after surgery to obtain 5/6Nx rats' 12-week serum. Then we detected the expression of E-cadherin in renal tubular epithelial cells of the remaining kidney and we investigated whether the 12th week serum of 5/6Nx rats could cause HK-2 (human kidney proximal tubular cell line) cells to transdifferentiate into fibroblasts. RESULTS: Our data confirmed that E-cadherin expression decreased significantly in the remaining kidney at 12 weeks, and the 5/6Nx rats' 12-week serum could suppress E-cadherin protein and mRNA expression (p < 0.05). We also found that the 5/6Nx rats' 12-week serum could upregulate ZEB1, ß-catenin, and wnt3 protein expression (p < 0.05). CONCLUSIONS: Our results demonstrated that the 5/6Nx rats' 12-week serum could suppress the expression of E-cadherin in HK-2 cells. It was partially through modulating the increase of ZEB1. The loss of E-cadherin could lead ß-catenin to localize to the cytoplasm and nucleus, and feed into the Wnt signaling pathway. It means that the pathogenic serum in chronic kidney disease (CKD) plays an important role in the loss of renal function and turns to be a new avenue of research with potential clinical implications.