Search Results (112)

This study evaluated the impact of fermented palm kernel meal (FPKM) on the lactation performance, blood biochemical indices, rumen microbiota, and metabolic functions of Holstein dairy cows, aiming to enhance the nutritional value of palm kernel meal (PKM) through solid-state fermentation. A 3 × 3 Latin square design was used, involving 12 multiparous Holstein cows (parity = 3; body weight = 625 ± 25.8 kg; days in milk = 103 ± 19.6 day(s); milk yield = 32.6 ± 1.58 kg/d) over three 28-day periods. Cows were randomly assigned to three isocaloric and isonitrogenous diets: a basal diet with wheat bran (WB group), a diet with wheat bran replaced by PKM (PKM group), and a diet with wheat bran replaced by FPKM (FPKM group). Solid-state fermentation improved PKM’s nutritional profile by reducing fiber and β-mannan content while increasing protein availability and ruminal degradability. Compared to the WB group, the PKM group showed lower dry matter intake, milk yield, and nutrient digestibility. In contrast, the FPKM group had higher DMI and milk yield than the PKM group, improved nutrient digestibility, and the highest energy-corrected milk yield due to increased milk protein and lactose production. The FPKM group also had higher concentrations of total volatile fatty acids, propionate, acetate, and microbial protein synthesis than the PKM group. Pro-inflammatory cytokines (tumor necrosis factor-α, interleukin-8) were elevated in the PKM group but were reduced to levels similar to the WB group in the FPKM group. Plasma immunoglobulin G levels were higher in both the FPKM and WB groups compared to the PKM group. The FPKM group also showed increased relative abundances of Prevotella, Fibrobacterota, and Verrucomicrobiota, while Bacillota and Ruminococcus were reduced compared to the WB group. Metabolomic profiling revealed that FPKM upregulated energy metabolism and inflammation-related pathways, increasing metabolites such as riboflavin and adenine and decreasing succinic acid and guanine compared to the PKM group. In conclusion, FPKM improved the feeding value of PKM-based material and showed more favorable responses than PKM, with generally comparable responses to WB, supporting its potential as an alternative feed ingredient for lactating dairy cows. Full article

Gut lactic acid bacteria are emerging as potential targets for modulating host purine metabolism and alleviating hyperuricemia-related disorders. This study aimed to isolate purine-degrading lactic acid bacterial strains from porcine intestine and systematically evaluate their probiotic potential through both in vitro and in vivo approaches. A strain designated Pedio6-1 was isolated and identified as Pediococcus acidilactici based on 16S rRNA sequencing. In vitro assays demonstrated that P. acidilactici Pedio6-1 exhibited nearly complete adenine clearance (approaching 100%) and a total purine clearance rate of 30.73%, along with strong tolerance to acidic conditions, bile salts, and gastrointestinal enzymes. To further assess its in vivo efficacy, a high-fat diet-induced obese mouse model was employed. After 8 weeks of intervention, Pedio6-1 supplementation significantly reduced the final body weight and liver index, and markedly decreased hepatic guanine levels (p < 0.05), with a trend toward lower total purine content compared to the obese control group. Mechanistically, Pedio6-1 treatment significantly downregulated the hepatic mRNA expression of pro-inflammatory cytokines IL-1β and TLR4 (p < 0.05). Serum untargeted metabolomics revealed that Pedio6-1 treatment shifted the metabolic profile toward that of normal diet-fed mice, with differential pathways predominantly enriched in porphyrin metabolism and amino acid biosynthesis and metabolism. Notably, key metabolites with antioxidant and metabolic regulatory functions, including bilirubin, biliverdin, glutathione, citrate, L-cystathionine, and 4-pyridoxic acid, were significantly elevated following treatment, while N-acetylornithine and methylmalonate ester were decreased, indicating coordinated remodeling of oxidative stress defense, vitamin B6 homeostasis, and energy metabolism. Collectively, these findings indicate that Pedio6-1 not only possesses direct purine-degrading activity in vitro, but also ameliorates purine metabolic disturbances, inflammation, and oxidative stress in obese mice, likely through the modulation of porphyrin and amino acid metabolic pathways, highlighting its promise as a functional probiotic candidate for managing obesity-associated purine metabolic disorders. Full article

Alterations of gut microbiota are common in chronic kidney disease (CKD) and contribute to increased uremic toxins including indoxyl sulfate (IS), p-cresyl sulfate (pCS) and trimethylamine N-oxide (TMAO), which are linked to cerebrovascular disease risk. This study examined the kidney–gut–brain axis in CKD mice and in dialysis patients. Male and female mice with adenine-induced CKD were fed a high-amino-acid (HAA) diet to increase precursors of gut-derived uremic toxins. A subgroup of mice received antibiotics in drinking water to suppress gut microbiota and evaluate its role in toxin generation. Behavior tests, gut microbiome composition and brain histology for cerebral microhemorrhages were analyzed. CKD mice had higher serum levels of creatinine, cystatin C and gut-derived toxins, a 2.5-fold increase in brain microhemorrhages, and decreased locomotor activity. The HAA diet significantly increased serum TMAO but not IS and pCS, and all three toxins were reduced by antibiotic therapy. Sex differences were observed; in male animals, higher TMAO was associated with increased brain microhemorrhages, whereas in female mice, pCS was associated with brain microhemorrhage burden. The suppression of toxins with antibiotics improved working memory in male animals. Gut microbiota analysis revealed the expansion of Lactobacillus and Ileibacterium in CKD mice. The HAA diet and antibiotics altered gut microbiota composition without changing alpha diversity. The human study utilized biobanked serum samples and a retrospective review of brain imaging scans in a hemodialysis patient cohort; TMAO levels were associated with increased lobar microbleeds. Our study supports a role for bacterial-derived uremic toxins in the kidney–gut–brain axis and cerebral microhemorrhage formation in CKD. Full article

Chronic kidney disease (CKD) affects nearly 10% of the global population, yet diagnosis and disease monitoring still rely primarily on plasma creatinine. Because creatinine levels are strongly influenced by non–renal factors, such as age, sex, muscle mass, and diet, its accuracy as a kidney function marker is limited. To identify plasma biomarkers that reflect kidney injury, we applied untargeted and targeted metabolomics in the adenine-induced CKD mouse model, a well-known tubular damage model, and validated the findings in plasma from patients with advanced CKD and healthy controls. We identified five metabolites that showed altered plasma levels in both experimental and human CKD, of which galactonic acid, pipecolic acid, and N-acetylneuraminic acid were significantly associated with measured glomerular filtration rate (GFR). As a proof-of-concept, we demonstrated that integrating these metabolites into a biomarker panel alongside creatinine could improve GFR estimation compared with creatinine alone. Our study introduces a promising metabolite-based biomarker panel that might enhance the accuracy of kidney function assessment and could potentially support diagnosis, risk stratification, and monitoring of disease progression; however, validation in a broader CKD cohort is needed. Full article

Background: Chronic kidney disease (CKD) is characterized by irreversible structural damage and functional deterioration of the kidneys. Esculetin (ES), with its anti-inflammatory, antioxidant, and immunomodulatory activities, shows potential in delaying renal function decline. This study aimed to investigate the protective effect of ES on adenine-induced CKD in mice and its underlying molecular mechanism, with a focus on its role in preventing the transition from acute kidney injury (AKI) to CKD. Methods: A AKI-to-CKD transition mice model was established by feeding mice a 0.2% adenine diet, and ES (30, 60 mg/kg) was co-administered for 4 weeks as a prophylactic intervention. Serum creatinine (SCr), blood urea nitrogen (BUN), and renal histopathology (HE, Masson, IHC) were evaluated to assess renal injury. Network pharmacology and transcriptomics were combined to screen the targets, and Western blot was used to verify the signaling pathways. Results: ES significantly reduced SCr and BUN levels in CKD mice and alleviated renal tubular dilation and inflammatory infiltration. ES decreased pro-inflammatory factors (IL-1β, IL-6, TNF-α) and MDA levels and enhanced SOD activity. Additionally, ES inhibited renal interstitial collagen deposition and reversed epithelial–mesenchymal transition (EMT) by upregulating E-cadherin and downregulating α-SMA levels. Mechanism studies confirmed that ES significantly inhibited the phosphorylation levels of p-EGFR, p-SRC, p-PI3K, p-AKT, and p-p65 in renal tissues. Conclusions: ES effectively inhibits inflammation, oxidative stress, and fibrosis by modulating the EGFR/SRC/PI3K/AKT/NF-κB signaling axis, thereby preventing the AKI-to-CKD transition in the adenine-induced renal injury model and alleviating the progression of chronic renal damage. Full article

Chronic kidney disease (CKD) involves uremic toxin-driven tubular injury and systemic vascular dysfunction, in which mitochondrial impairment and apoptotic cell loss contribute to progressive tissue deterioration. Accordingly, a targeted EV platform is required to enable efficient miRNA delivery to the toxin-stressed tubular–endothelial compartment. Based on our previous study showing that melatonin restores miR-4516 levels under CKD-related stress, we directly loaded miR-4516 into engineered extracellular vesicles (EVs) to evaluate its effects on mitochondrial function and cell survival. Here, we engineered EVs with a G3-C12/RGD surface modification and established a miR-4516 loading strategy to enhance delivery to kidney proximal tubule cells and vascular endothelial cells. miR-4516 loading increased EV-associated miR-4516 levels without major changes in particle size distribution, and EV identity was supported by CD9 and CD81 expression. Confocal microscopy and flow cytometry demonstrated increased cellular uptake of miR-4516-loaded G3-C12/RGD-EVs compared with control EVs in TH1 proximal tubule cells and HUVECs. Under indoxyl sulfate stress, engineered EV treatment restored intracellular miR-4516 and improved mitochondrial function, as indicated by recovery of respiratory Complex I and Complex IV activities and improved Seahorse bioenergetic parameters (OCR/ECAR, basal and maximal respiration, ATP-linked respiration, and spare respiratory capacity). Annexin V staining further indicated reduced toxin-induced apoptosis. In an adenine diet-induced CKD mouse model, intravenous administration of miR-4516-loaded G3-C12/RGD-EVs improved urinary albumin-to-creatinine ratio (UACR), blood urea nitrogen (BUN), and serum creatinine. These findings indicate that miR-4516-loaded, targeting-engineered EVs may mitigate uremic toxin-associated mitochondrial dysfunction and renal impairment in CKD. Full article

Background: Hyperuricemia (HUA) is a metabolic disorder that severely threatens human health. Chronic uric acid (UA) overload promotes the progression of tubulointerstitial fibrosis (TIF), leading to impaired UA excretion. Our previous studies identified HIPK2 inhibitor XRF-1021, which exhibits robust anti-TIF activity and lowers UA levels in vivo. This study aimed to elucidate its UA-lowering mechanism and therapeutic potential for HUA. Methods: Uricase and xanthine oxidase (XOD) assays were performed to assess effects on UA degradation/production. HEK293T cells transiently expressing UA transporters and gene-knockdown rats were used to evaluate transporter inhibition, while HK-2 cells were analyzed by Western blot. Pharmacokinetics were characterized in rats. Efficacy was tested in potassium oxonate-induced acute HUA rats, diet/adenine-induced chronic HUA quails, and adenine-induced mice with HUA secondary to TIF. Maximum tolerated dose and long-term toxicity were assessed in rats. Results: XRF-1021 neither activated uricase nor inhibited XOD, indicating no direct effect on UA catabolism or synthesis. Instead, XRF-1021 inhibited URAT1 and GLUT9, reducing renal UA reabsorption, while sparing OAT3, OAT4, and ABCG2 activity and upregulating OAT3 and NPT4, suggesting minimal risk of disrupting drug or uremic toxin handling. XRF-1021 showed dose-dependent systemic exposure in rats, lowered serum UA, and provided renal protection in vivo. LD₅₀ values were 2345.4 mg/kg (male) and 1078.9 mg/kg (female), with no obvious toxicity after long-term dosing. Conclusions: XRF-1021 lowers UA by inhibiting URAT1 and GLUT9 to enhance renal UA excretion and provides kidney protection, supporting XRF-1021 as a promising candidate for HUA therapy. Full article

Dietary pattern characterized by low intake of vegetables and fruits and high consumption of fat, soft drink and desserts are associated with an increased risk of chronic diseases. To investigate the effects of folate status and fructose intake on adenine-induced chronic kidney disease (CKD), seven-week-old C57BL/6 mice were divided into six groups and fed either a control diet (Ctrl), a 26% (w/w) high-fructose diet (Hfru), Ctrl plus 0.15% adenine (Ctrl+ade), Hfru+ade, Hfru with folate deficiency plus adenine (Hfru−f+ade), or Hfru with tenfold folate supplementation plus adenine (Hfru+f10+ade). After 10 weeks on the assigned diets, adenine was administrated to the +ade groups for 7 weeks. The results showed that all adenine-treated mice exhibited increased fasting blood glucose, urinary glucose, and elevated renal expression of collagen 1a1 (Col1a1), fibronectin (Fn1), and smooth muscle α-actin (Acta2). Compared with Ctrl mice, Hfru-fed mice showed significantly higher serum creatinine, increased urinary protein, and reduced creatinine clearance. Adenine induced kidney injury in all +ade groups, with the most severe damage observed in Hfru−f+ade mice, as indicated by elevated blood urine nitrogen (BUN), urinary protein, neutrophil gelatinase-associated lipocalin (NGAL), and renal fibrosis. In contrast, Hfru+f10+ade mice showed the lowest levels of these renal injury markers. The Hfru+ade diets increased renal Hif1α and iNos gene expression, which was further exacerbated by folate deficiency. Secretion of the anti-inflammatory cytokine interleukin (IL-10) by splenocytes was significantly reduced under folate-deficient conditions. Renal IL-10 levels were suppressed in all +ade groups but were significantly increased by folate supplementation. Renal IL-10 levels were negatively correlated with the inflammatory chemokine monocyte chemoattractant protein (MCP-1) and transforming growth factor (TGF)-β, whereas renal MCP-1 levels showed positive correlations with TGF-β and IL-6. Overall, these findings suggest that high fructose consumption in the absence of adequate folate intake may be of concern for CKD progression. Full article

Cardiovascular diseases are a major cause of morbidity and mortality in chronic kidney disease (CKD) patients. Integrin-linked kinase (ILK) regulates integrin–extracellular matrix interactions and vascular integrity. This study investigated the role of ILK in CKD-associated vascular alterations. An adenine-supplemented diet induced a progressive CKD in wild-type (WT) and conditional ILK knock-down (cKD-ILK) mice. Aortic tissue was collected for histology and RT-qPCR analysis. Moreover, aortas were incubated ex vivo with the uremic toxins p-cresyl sulfate and indoxyl sulfate. In vitro, human aortic vascular smooth muscle cells were exposed to uremic toxins, and the effect of siRNA-mediated ILK silencing was tested. Aortas of adenine-fed WT mice showed a progressive increase in ILK expression, morphological alterations, and increased fibrosis, which was not observed in cKD-ILK aortas, compared to control mice. Statistically significant correlations between vascular content of ILK and fibrosis markers were observed. Ex vivo, uremic toxins increased ILK and fibrosis protein expression in WT aortas but not in cKD-ILK. In vitro, uremic toxins increased ILK activity and fibrosis markers, like collagen, while ILK-deleted cells prevented collagen increase. ILK depletion prevents CKD-associated vascular fibrosis, suggesting ILK as a potential therapeutic target to prevent arterial alterations in renal patients. Full article

Sarcopenia, the progressive loss of muscle mass and strength, is a common complication in patients with chronic kidney disease (CKD). This condition arises from a combination of factors including reduced physical activity, insufficient protein intake, hyperphosphatemia, chronic inflammation, and uremia itself; however, the underlying molecular mechanisms remain poorly understood. Proteolysis in skeletal muscle is primarily controlled by the ubiquitin–proteasome system, autophagy–lysosome system, and calpains (CAPNs) cysteine proteases, which degrade structural proteins and mediate cell signaling. This study aims to investigate the role of CAPNs in CKD-associated muscle deterioration. CKD was induced in mice through an adenine-rich diet for 2, 4 and 6 weeks. The involvement of CAPNs in CKD-related sarcopenia was assessed using mice that overexpressed the CAPNs endogenous inhibitor, calpastatin (CAST). Gastrocnemius muscle strength, structural integrity, and function were evaluated. Mice with CKD showed elevated CAPNs, particularly CAPN2, expression and activity in the gastrocnemius, in parallel with significant muscle deterioration, including strength loss, structural damage, and impaired muscle performance. Overexpression of CAST prevented muscle strength loss, improved muscle function and structure without affecting renal function, and reversed fibrosis, inflammation and adipogenesis expression markers. Targeting CAPN2 could be a promising therapeutic strategy to mitigate muscle damage and improve physical performance in CKD patients. Full article

Chronic kidney disease (CKD) causes a variety of health problems including renal dysfunction and cardiovascular disease. This study aimed to investigate whether the probiotic strain Lactiplantibacillus plantarum HY7718 (HY7718) can protect against CKD using HK2 cells and a CKD mouse model, generated by feeding mice a diet containing 0.15% adenine. In vitro tests showed that HY7718 was anti-inflammatory in H₂O₂-treated HK2 cells and reduced apoptosis of tumor necrosis factor-α/cycloheximide-induced HK2 cells. In the adenine-induced CKD model, markers of renal dysfunction (blood urea nitrogen (BUN) and creatinine (Crea)) and inorganic calcium and phosphorus were markedly increased. However, oral administration of HY7718 (10⁸ colony-forming units/kg/day) significantly attenuated these increases. HY7718 also reduced the kidney histopathological score, including tubular necrosis, cast formation, and tubular dilatation, as well as the mononuclear cell infiltration score in kidney tissue, suggesting that it could reverse the progression of CKD. Additionally, HY7718 downregulated the renal expression of pro-inflammatory cytokine genes and members of the TLR/NF-κB signaling pathway. Furthermore, HY7718 reduced tubule apoptotic cells and expression of apoptosis-related genes, indicating that it is potentially renoprotective. These results demonstrate that supplementation with the probiotic HY7718 can ameliorate CKD symptoms by improving renal function and reducing kidney injury. Full article

Background: Phelan–McDermid syndrome (PMS), caused by SHANK3 variants or 22q13.3 deletions, often includes systemic features such as gastrointestinal and hepatic abnormalities. This study highlights the overlap between PMS and metabolic-associated steatotic liver disease (MASLD), focusing on PNPLA3 variants and underscoring the need for structured metabolic monitoring. Methods: We describe a 25-year-old male with PMS due to a 22q13.33 microdeletion involving SHANK3. He exhibited developmental delay, seizures, and hypotonia. Genetic testing revealed homozygosity for the PNPLA3 p.I148M variant. Clinical, anthropometric, biochemical, imaging, and metabolic investigations were performed, including liver ultrasound and metabolic profiling of lymphoblastoid cell lines. Results: Ultrasound revealed moderate hepatic steatosis consistent with MASLD. After ursodeoxycholic acid treatment and a Mediterranean-style diet, steatosis improved to mild. Metabolic profiling demonstrated increased nicotinamide adenine dinucleotide generation under metabolic stimuli, suggesting altered energy homeostasis. Conclusions: We highlight the contribution of PNPLA3 to MASLD in PMS and support systematic hepatic monitoring. Genotype–phenotype associations in PMS may provide insights relevant to MASLD research and clinical management. Full article

The prevalence of hyperuricemia with elevated serum uric acid is increasing worldwide. However, the effects of high uric acid on diabetic patients with dyslipidemia and the mechanisms underlying these effects remain unexplored. This study aimed to develop a novel diabetic model of hyperuricemia and dyslipidemia in male hamsters to evaluate the effects of high uric acid on glucolipid metabolism, renal injury and the gut microbiota. Twelve healthy hamsters were randomly divided into two groups and fed with a normal diet and high-fat/cholesterol diet (HFCD), respectively. Twenty-four diabetic hamsters were randomly divided into four groups receiving a normal diet; HFCD; potassium oxonate (PO) treatment (intragastric PO at doses of 350 mg/kg and adenine at doses of 150 mg/kg with 5% fructose water); and PO treatment with HFCD, respectively. After 4 weeks, all animals were dissected for determining serum biochemical indicators, tissue antioxidant parameters, renal pathological changes, target gene expressions, fecal short-chain fatty acids content, and the gut microbiota composition. The results showed that a hamster model with hyperuricemia and dyslipidemia was successively established by the combination of PO treatment and HFCD, in which serum uric acid, glucose, triglyceride and total cholesterol levels reached 499.5 ± 61.96 μmol/L, 16.88 ± 2.81 mmol/L, 119.88 ± 27.14 mmol/L and 72.92 ± 16.62 mmol/L, respectively. PO treatment and HFCD had synergistic effects on increasing uric acid, urea nitrogen, creatinine levels, liver xanthine oxidase activity, plasminogen activator inhibitor-1 and transforming growth factor-β expressions, and the relative abundance of Lleibacterium (p < 0.05); in addition, they caused glomerular mesangial cells and matrix proliferation, protein casts and urate deposition. High uric acid was closely related to decreased antioxidant capacity; decreased renal vascular endothelial growth factor expression; increased acetic acid content; decreased butyric, propanoic, and isobutyric acid levels; decreased Firmicutes to Bacteroidetes ratios (p < 0.05); and altered epithelial integrity and structure of the gut microbiota in diabetic hamsters. The findings indicate that high uric acid affects the glucolipid metabolism, accelerates renal damage, and disrupts the balance of intestinal flora in diabetic animals, which provides a scientific basis for metabolic syndrome prevention and control in diabetes. Full article

Extra-osseous calcification refers to the pathological deposition of calcium salts in soft tissues. Its most recognized forms affect the cardiovascular system, leading to vascular and heart valve calcifications. This process is active and regulated, involving the phenotype transition of resident cells into osteo/chondrogenic lineage. Chronic kidney disease (CKD) patients frequently suffer from vascular and other soft tissue calcification. OsteoSense dyes are fluorescent imaging agents developed to visualize calcium deposits during bone formation. In addition to its application in bone physiology, it has been used to detect vascular smooth muscle cell calcification in vitro and to evaluate calcification ex vivo. Here, we investigated CKD-associated soft tissue calcification by applying OsteoSense in vivo. CKD was induced by a diet containing adenine and elevated phosphate. OsteoSense (80 nmol/kg body weight) was injected intravenously through the retro-orbital venous sinus 18 h before the measurement on an IVIS Spectrum In Vivo Imaging System. OsteoSense staining detected calcium deposition in the aorta, kidney, heart, lung, and liver in CKD mice. On the other hand, no calcification occurred in the brain, eye, or spleen. OsteoSense positivity in the calcified soft tissues in CKD mice was associated with increased mRNA levels of osteo/chondrogenic transcription factors. Our findings demonstrate that OsteoSense is a sensitive and effective tool for detecting soft tissue calcification in vivo, and may be particularly valuable for studies of CKD-related ectopic calcification. Full article

Previous work has shown that mouse models fed a non-obesogenic high-fat diet have preserved cardiac function and no obesity-associated comorbidities such as diabetes. However, they do suffer increased cardiac vulnerability to ischemic reperfusion (I/R) injury, which has been attributed to changes in Ca²⁺ handling, oxidative stress, and mitochondrial transition pore activity. However, there have been no studies investigating the involvement of metabolites. Wild-type mice were fed either a control or a non-obesogenic high-fat diet for ~26 weeks. Key cardiac metabolites were extracted from freshly excised hearts and from hearts exposed to 30 min global ischemia followed by 45 min reperfusion. The extracted metabolites were measured using commercially available kits and HPLC. Hemodynamic cardiac function was monitored in Langendorff perfused hearts. Levels of energy-rich phosphates and related metabolites were similar for both hearts fed a control or a high-fat diet. However, the high-fat diet decreased cardiac glycogen and increased cardiac lactate, hypoxanthine, alanine, and taurine levels. Langendorff perfused hearts from the high-fat diet group suffered more ischemic stress during ischemia, as shown by the significantly shorter time needed for onset and for reaching maximal ischemic (rigor) contracture. Following I/R, there was a significant decrease in myocardial adenine nucleotides and a significant increase in the levels of alanine and purines for both groups. Most of the principal amino acids tended to fall during I/R. Hearts from mice fed a high-fat diet showed more changes during I/R in markers of energetics (phosphorylation potential and energy charge), metabolic stress (lactate), and osmotic stress (taurine). This study suggests that cardiac metabolic changes due to high-fat diet feeding, independent of obesity-related comorbidities, are responsible for the marked metabolic changes and the increased vulnerability to I/R. Full article