Development of tenofovir monobenzyl ester phosphonoamidate prodrugs with improved anti-hepatitis B virus activity and intrahepatic tenofovir enrichment.

Various tenofovir (TFV) prodrugs have been developed by introducing masking groups to the hydroxyls of the monophosphonate group to enhance intestinal absorption efficiency and therapeutic effects. However, the reported TFV prodrugs have drawbacks such as low bioavailability, systemic toxicity caused by their breakdown in non-targeted tissues, and potential low intracellular conversion efficiency. In the present study, we developed a class of TFV monobenzyl ester phosphonoamidate prodrugs without substitutions on the benzene ring. Compared with previous TFV prodrugs, compounds 3a and 3b developed in the present study showed higher anti-hepatitis B virus activity, stronger stability and higher levels of intrahepatic enrichment of the metabolic product (TFV), indicating the potential of these compounds as novel prodrugs with high efficiency and low systemic toxicity for the treatment of hepatitis B.

Huang Gan Formula Alleviates Systemic Inflammation and Uremia in Adenine-Induced Chronic Kidney Disease Rats May Associate with Modification of Gut Microbiota and Colonic Microenvironment.

Purpose: This study aims to investigate the effects of Huang Gan formula (HGF), a Chinese herbal prescription used for chronic kidney disease (CKD), on the regulation of the gut microbiota and colonic microenvironment of CKD. Methods: CKD rats were induced by 150 mg/kg adenine gavage for 4 weeks, then orally treated with or without 3.6 g/kg or 7.2 g/kg of HGF for 8 weeks. The renal function and structure were analyzed by biochemical detection, hematoxylin and eosin, Masson's trichrome, Sirius red and immunochemical staining. Average fecal weight and number in the colon were recorded to assess colonic motility. Further, the changes in the gut microbiota and colonic microenvironment were evaluated by 16S rRNA sequencing, RT-PCR or immunofluorescence. The levels of inflammatory cytokines, uremic toxins, and NF-κB signaling pathway were detected by RT-PCR, ELISA, chloramine-T method or Western blotting. Redundancy analysis biplot and Spearman's rank correlation coefficient were used for correlation analysis. Results: HGF significantly improved renal function and pathological injuries of CKD. HGF could improve gut microbial dysbiosis, protect colonic barrier and promote motility of colonic lumens. Further, HGF inhibited systemic inflammation through a reduction of TNF-α, IL-6, IL-1ß, TGF-ß1, and a suppression of NF-κB signaling pathway. The serum levels of the selected uremic toxins were also reduced by HGF treatment. Spearman correlation analysis suggested that high-dose HGF inhibited the overgrowth of bacteria that were positively correlated with inflammatory factors (eg, TNF-α) and uremic toxins (eg, indoxyl sulfate), whereas it promoted the proliferation of bacteria belonging to beneficial microbial groups and was positively correlated with the level of IL-10. Conclusion: Our results suggest that HGF can improve adenine-induced CKD via suppressing systemic inflammation and uremia, which may associate with the regulations of the gut microbiota and colonic microenvironment.

Infliximab abrogates adenine-induced chronic kidney disease via modulation of the MAPK/JNK/ASK signaling pathway in rats.

Chronic kidney disease (CKD) is a prominent cause of death worldwide. Infliximab is one of the anti-TNF-α; herein, we studied the effect of infliximab on adenine-induced CKD. To inspect the role of infliximab, either ameliorative or curative, on CDK induced with adenine. Thirty Wistar albino rats were separated into five groups of 6 rats' each: rats of group Ι were kept as control given saline, rats of group II were treated with infliximab (5 mg/kg, i.p.) for 5 weeks, rats of group ΙΙΙ (the diseased group) had an adenine containing diet (0.25% W/W in feed) for 5 weeks, rats of group ΙV (the ameliorative group) had an adenine-containing diet and infliximab (5 mg/kg, i.p.) for 5 weeks simultaneously, and rats of group V (the curative group) had adenine containing diet then a single dose of infliximab (5 mg/kg, i.p.) was given in the 6th week. Infliximab treatment revealed a decrease in the plasma levels of urea, creatinine, NGAL, and MDA with a substantial increase in TAC. Also, inflammatory mediators such as IL-6 and NF-κB were significantly decreased with the down-regulation of the ASK1/MAPK/JNK pathway. Caspase 3 was downregulated. Also, infliximab treatment exhibited improvement in the histological and immunohistochemical kidney changes. Through its involvement in reducing oxidative stress, inflammation, and apoptosis, infliximab has an ameliorative and curative effect on CKD induced with adenine.

Fisetin ameliorates fibrotic kidney disease in mice via inhibiting ACSL4-mediated tubular ferroptosis.

Kidney fibrosis is the hallmark of chronic kidney disease (CKD) progression, whereas no effective anti-fibrotic therapies exist. Recent evidence has shown that tubular ferroptosis contributes to the pathogenesis of CKD with persistent proinflammatory and profibrotic responses. We previously reported that natural flavonol fisetin alleviated septic acute kidney injury and protected against hyperuricemic nephropathy in mice. In this study, we investigated the therapeutic effects of fisetin against fibrotic kidney disease and the underlying mechanisms. We established adenine diet-induced and unilateral ureteral obstruction (UUO)-induced CKD models in adult male mice. The two types of mice were administered fisetin (50 or 100 mg·kg-1·d-1, i.g.) for 3 weeks or 7 days, respectively. At the end of the experiments, the mice were euthanized, and blood and kidneys were gathered for analyzes. We showed that fisetin administration significantly ameliorated tubular injury, inflammation, and tubulointerstitial fibrosis in the two types of CKD mice. In mouse renal tubular epithelial (TCMK-1) cells, treatment with fisetin (20 µM) significantly suppressed adenine- or TGF-ß1-induced inflammatory responses and fibrogenesis, and improved cell viability. By quantitative real-time PCR analysis of ferroptosis-related genes, we demonstrated that fisetin treatment inhibited ferroptosis in the kidneys of CKD mice as well as in injured TCMK-1 cells, as evidenced by decreased ACSL4, COX2, and HMGB1, and increased GPX4. Fisetin treatment effectively restored ultrastructural abnormalities of mitochondrial morphology and restored the elevated iron, the reduced GSH and GSH/GSSG as well as the increased lipid peroxide MDA in the kidneys of CKD mice. Notably, abnormally high expression of the ferroptosis key marker ACSL4 was verified in the renal tubules of CKD patients (IgAN, MN, FSGS, LN, and DN) as well as adenine- or UUO-induced CKD mice, and in injured TCMK-1 cells. In adenine- and TGF-ß1-treated TCMK-1 cells, ACSL4 knockdown inhibited tubular ferroptosis, while ACSL4 overexpression blocked the anti-ferroptotic effect of fisetin and reversed the cytoprotective, anti-inflammatory, and anti-fibrotic effects of fisetin. In summary, we reveal a novel aspect of the nephroprotective effect of fisetin, i.e. inhibiting ACSL4-mediated tubular ferroptosis against fibrotic kidney diseases.

Bi Xie Fen Qing Yin decoction alleviates potassium oxonate and adenine induced-hyperuricemic nephropathy in mice by modulating gut microbiota and intestinal metabolites.

This study aimed to evaluate the preventive effect of Bi Xie Fen Qing Yin (BXFQY) decoction on hyperuricemic nephropathy (HN). Using an HN mouse model induced by oral gavage of potassium oxonate and adenine, we found that BXFQY significantly reduced plasma uric acid levels and improved renal function. Further study shows that BXFQY suppressed the activation of the NLRP3 inflammasome and decreased the mRNA expressions of pro-inflammatory and fibrosis-associated factors in renal tissues of HN mice. Also, BXFQY prevented the damage to intestinal tissues of HN mice, indicative of suppressed colonic inflammation and increased gut barrier integrity. By 16 S rDNA sequencing, BXFQY significantly improved gut microbiota dysbiosis of HN mice. On the one hand, BXFQY down-regulated the abundance of some harmful bacteria, like Desulfovibrionaceae, Enterobacter, Helicobacter, and Desulfovibrio. On the other hand, BXFQY up-regulated the contents of several beneficial microbes, such as Ruminococcaceae, Clostridium sensu stricto 1, and Streptococcus. Using gas or liquid chromatography-mass spectrometry (GC/LC-MS) analysis, BXFQY reversed the changes in intestinal bacterial metabolites of HN mice, including indole and BAs. The depletion of intestinal flora from HN or HN plus BXFQY mice confirmed the significance of gut microbiota in BXFQY-initiated treatment of HN. In conclusion, BXFQY can alleviate renal inflammation and fibrosis of HN mice by modulating gut microbiota and intestinal metabolites. This study provides new insight into the underlying mechanism of BXFQY against HN.

Profiling of adenine-derived signaling molecules, cytokinins, in myotubes reveals fluctuations in response to lipopolysaccharide-induced cell stress.

Cytokinins (CTKs) are a diverse collection of evolutionarily conserved adenine-derived signaling molecules classically studied as phytohormones; however, their roles and production have been less studied in mammalian systems. Skeletal muscles are sensitive to cellular cues such as inflammation and in response, alter their secretome to regulate the muscle stem cell and myofiber niche. Using cultured C2C12 muscle cells, we profiled CTK levels to understand (1) whether CTKs are part of the muscle secretome and (2) whether CTKs are responsive to cellular stress. To induce cellular stress, C2C12 myotubes were treated with lipopolysaccharides (LPS) for 24 h and then media and cell fractions were collected for ultra high-performance liquid chromatography tandem mass spectrometry with electrospray ionization (UHPLC-(ESI+)-HRMS/MS) for metabolomics and CTK profiling. Across LPS-treated and control cells, 11 CTKs were detected in the extracellular space while 6 were detected intracellularly. We found that muscle cells are enriched in isopentenyladenine (iP) species (from free base, riboside to nucleotide forms), and that extracellular levels are increased after LPS treatment. Our study establishes that muscle cells express various forms of CTKs, and that CTK levels are responsive to LPS-induced cell stress, suggesting a role for CTKs in intra- and extracellular signaling of mammalian cells.

Impact of Combination Antiretroviral Treatment on Liver Metabolic Health in HIV-Infected Persons.

In the last three decades, there has been a considerable improvement in human immunodeficiency virus (HIV) therapy. Acquired immunodeficiency syndrome (AIDS) is no longer a common cause of death for people living with HIV (PLWH) in developed countries, and co-infections with hepatitis viruses can be effectively managed. However, metabolic syndrome and metabolic dysfunction-associated steatotic liver disease (MASLD) are emerging threats these days, especially as the HIV-positive population gets older. The factors for MASLD development in PLWH are numerous, including non-specific (common for both HIV-positive and negative) and virus-specific. We focus on what is known for both, and in particular, on the burden of antiretroviral therapy (ART) for metabolic health and liver damage. We review data on contemporary drugs, including different groups and some particular agents in those groups. Among current ART regimens, the switch from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide fumarate (TAF) and particularly its combination with integrase inhibitors (INSTIs) appear to have the most significant impact on metabolic disturbances by increasing insulin resistance, which over the years promotes the evolution of the cascade leading to metabolic syndrome (MetS), MASLD, and eventually metabolic dysfunction-associated steatohepatitis (MASH).

Combined Exogenous Activation of Bovine Oocytes: Effects on Maturation-Promoting Factor, Mitogen-Activated Protein Kinases, and Embryonic Competence.

Oocyte activation via dual inhibition of protein synthesis and phosphorylation has improved in vitro embryo production in different mammalian species. In this study, we evaluated the effects of the combination of cycloheximide (CHX), dimethyl amino purine (DMAP), and anisomycin (ANY) on the activation of bovine oocytes, particularly on dynamics of MPF and MAPKs, embryonic developmental potential, and quality. The results showed that the cleavage and blastocyst rates, as well as levels of CCNB1, CDK1, p-CDK1Thr161, and p-CDK1Thr14-Tyr15, were similar among groups; ANY and ANY + CHX reduced the expression of ERK1/2 compared to DMAP-combinations (p < 0.05), whereas ANY + DMAP, CHX + DMAP, and ANY + CHX + DMAP reduced p-ERK1/2 compared to ANY and ANY + CHX treatments (p < 0.05). The quality of blastocysts in terms of cell counts, their allocation, and the numbers of TUNEL-positive cells did not differ among groups. However, transcript levels of POU5F1 were higher in embryos derived from ANY + CHX + DMAP treatment compared to other groups, while expression levels of CDX2 did not show differences. In addition, the BCL2A1/BAX ratio of the ANY + CHX + DMAP treatment was significantly low compared to the ANY treatment (p < 0.05) and did not differ significantly from the other treatments. In conclusion, oocyte activation by dual inhibition of protein synthesis and phosphorylation induces MPF inactivation without degradation of CCNB1, while MAPK inactivation occurs differentially between these inhibitors. Thus, although the combined use of these inhibitors does not affect early developmental competence in vitro, it positively impacts the expression of transcripts associated with embryonic quality.

Renoprotective Effects of Solid-State Cultivated Antrodia cinnamomea in Juvenile Rats with Chronic Kidney Disease.

Antrodia cinnamomea (AC), a medicinal mushroom, has multiple beneficial actions, such as acting as a prebiotic. The incidence of chronic kidney disease (CKD) in children has steadily increased year by year, and CKD is related to gut microbiota dysbiosis. Herein, we investigated the renoprotection of solid-state cultivated AC in adenine-induced CKD juvenile rats. CKD was induced in 3-week-old male rats by feeding with adenine (0.5%) for three weeks. Treated groups received oral administration of AC extracts at either a low (10 mg/kg/day) or high dose (100 mg/kg/day) for six weeks. At nine weeks of age, the rats were sacrificed. Renal outcomes, blood pressure, and gut microbiome composition were examined. Our results revealed that AC treatment, either low- or high-dose, improved kidney function, proteinuria, and hypertension in CKD rats. Low-dose AC treatment increased plasma concentrations of short-chain fatty acids (SCFAs). Additionally, we observed that AC acts like a prebiotic by enriching beneficial bacteria in the gut, such as Akkermansia and Turicibacter. Moreover, the beneficial action of AC against CKD-related hypertension might also be linked to the inhibition of the renin-angiotensin system. This study brings new insights into the potential application of AC as a prebiotic dietary supplement in the prevention and treatment of pediatric CKD.

Assessing bone mineral density in children and adolescents living with HIV and on treatment with tenofovir disoproxil fumarate: a systematic review.

OBJECTIVE: To investigate the impact of tenofovir disoproxil fumarate on bone mineral density and bone mineral content in children and adolescents infected with the human immunodeficiency virus. DATA SOURCE: The search procedure was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement. The search was carried out until April 2022 in Medical Literature Analysis and Retrieval System Online (Medline), Embase, Cochrane Central, Latin American and Caribbean Health Sciences Literature, Web of Science, Scopus, and MedRxiv. The combination of terms used was: (Children OR Youth OR Teenagers) AND HIV AND (Tenofovir OR "Antiretroviral therapy") AND ("Bone density" OR Osteoporosis OR Osteopenia). The protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO, CRD42022312851). DATA SYNTHESIS: The initial searches resulted in 1156 papers. After the exclusion of duplicate studies, three blinded reviewers analyzed the title and abstract of 563 papers, of which 57 remained to be read in full. Only nine papers met the eligibility criteria and were included in descriptive and risk-of-bias analyses. Regarding study design, four were cross-sectional, three were longitudinal before-after studies without a control group, and two were prospective cohorts. Among these nine papers, seven showed no significant association between tenofovir disoproxil fumarate use and reduced bone mass in young people. However, these papers did not have high methodological quality. CONCLUSIONS: Although most of the selected papers found no harmful effect of tenofovir disoproxil fumarate on bone mass, further primary research with higher methodological quality is needed so robust scientific evidences can be obtained.

GP120 and tenofovir alafenamide alter cannabinoid receptor 1 expression in hippocampus of mice.

Central nervous system (CNS) dysfunction remains prevalent in people with HIV (PWH) despite effective antiretroviral therapy (ART). There is evidence that low-level HIV infection and ART drugs may contribute to CNS damage in the brain of PWH with suppressed viral loads. As cannabis is used at a higher rate in PWH compared to the general population, there is interest in understanding how HIV proteins and ART drugs interact with the endocannabinoid system (ECS) and inflammation in the CNS. Therefore, we investigated the effects of the HIV envelope protein gp120 and tenofovir alafenamide (TAF) on cannabinoid receptor 1 (CB1R), glial fibrillary acidic protein (GFAP), and IBA1 in the brain and on locomotor activity in mice. The gp120 transgenic (tg) mouse model was administered TAF daily for 30 days and then analyzed using the open field test before being euthanized, and their brains were analyzed for CB1R, GFAP, and IBA1 expression using immunohistochemical approaches. CB1R expression levels were significantly increased in CA1, CA2/3, and dentate gyrus of gp120tg mice compared to wt littermates; TAF reversed these effects. As expected, TAF showed a medium effect of enhancing GFAP in the frontal cortex of gp120tg mice in the frontal cortex. TAF had minimal effect on IBA1 signal. TAF showed medium to large effects on fine movements, rearing, total activity, total distance, and lateral activity in the open-field test. These findings suggest that TAF may reverse gp120-induced effects on CB1R expression and, unlike tenofovir disoproxil fumarate (TDF), may not affect gliosis in the brain.

Endothelial Dysfunction in Superior Mesenteric Arteries Isolated from Adenine-Induced Renal Failure in Model Rats.

Endothelial dysfunction-a hallmark of chronic kidney disease (CKD)-is one of the major risk factors for cardiovascular diseases (CVD). Imbalances in endothelium-derived relaxing factors (EDRFs) and contracting factors (EDCFs) specific to endothelial dysfunction in CKD are yet to be studied. Therefore, using adenine-treated rats-a CKD rat model-we investigated the responsiveness of superior mesenteric artery (SMA) endothelium to acetylcholine (ACh) stimulation under different experimental conditions. Nine-week-old male Wistar rats were treated daily with adenine (200 and 600 mg/kg body weight) by oral gavage, for 10 d; the two groups were named adenine-200 (200 mg/kg body weight) and adenine-600 (600 mg/kg body weight). The systolic blood pressure (measured 1-, 8-, and 15 d post-treatment) was significantly increased in the adenine-600 group compared with that in the control group; whereas that in the adenine-200 group showed only a slight increase. Moreover, in the adenine-600 group the serum creatinine and blood urea nitrogen (BUN) levels (measured at 18 d post-treatment) were significantly elevated when compared with those in control or adenine-200 groups. The ACh-mediated relaxation was slightly reduced in the adenine-200 group. The ACh- and sodium nitroprusside (SNP)-mediated relaxations were impaired in the adenine-600 group. Although no ACh-mediated contraction was observed in the presence of a nitric oxide (NO) synthase inhibitor, ACh-induced endothelium-derived hyperpolarizing factor-mediated relaxation was largely impaired in the adenine-600 mg/kg group. This study revealed that in the SMA of adenine-induced CKD model rats, EDCF signaling remained unaltered while the NO and EDHF signaling were impaired.

Impaired renal ischemia reperfusion recovery after bilateral renal artery ligation in rats treated with adenine: role of renal mitochondria.

Vascular calcification (VC) and ischemia reperfusion (IR) injury is characterised to have mitochondrial dysfunction. However, the impact of dysfunctional mitochondria associated with vascular calcified rat kidney challenged to IR is not explored and is addressed in the present study. Male Wistar rats were treated with adenine for 20 days to induce chronic kidney dysfunction and VC. After 63 days, renal IR protocol was performed with subsequent recovery for 24 h and 7 days. Various mitochondrial parameters and biochemical assays were performed to assess kidney function, IR injury and its recovery. Adenine-induced rats with VC, decreased creatinine clearance (CrCl), and severe tissue injury demonstrated an increase in renal tissue damage and decreased CrCl after 24 h of IR (CrCl in ml: IR-0.220.02, VC-IR-0.050.01). Incidentally, the 24 h IR pathology in kidney was similar in both VC-IR and normal rat IR. But, the magnitude of dysfunction was higher with VC-IR due to pre-existing basal tissue alterations. We found severed deterioration in mitochondrial quantity and quality supported by low bioenergetic function in both VC basal tissue and IR challenged sample. However, post 7 days of IR, unlike normal rat IR, VC rat IR did not improve CrCl and corresponding mitochondrial damage in terms of quantity and its function were observed. Based on the above findings, we conclude that IR in VC rat adversely affect the post-surgical recovery, mainly due to the ineffective renal mitochondrial functional restoration from the surgery.

Chronic environmental hypoxia attenuates innate immunity activation and renal injury in two CKD models.

Tissue hypoxia has been pointed out as a major pathogenic factor in chronic kidney disease (CKD). However, epidemiological and experimental evidence inconsistent with this notion has been described. We have previously reported that chronic exposure to low ambient Po2 promoted no renal injury in normal rats and in rats with 5/6 renal ablation (Nx) unexpectedly attenuated renal injury. In the present study, we investigated whether chronic exposure to low ambient Po2 would also be renoprotective in two additional models of CKD: adenine (ADE) excess and chronic nitric oxide (NO) inhibition. In both models, normobaric ambient hypoxia attenuated the development of renal injury and inflammation. In addition, renal hypoxia limited the activation of NF-κB and NOD-like receptor family pyrin domain containing 3 inflammasome cascades as well as oxidative stress and intrarenal infiltration by angiotensin II-positive cells. Renal activation of hypoxia-inducible factor (HIF)-2α, along with other adaptive mechanisms to hypoxia, may have contributed to these renoprotective effects. The present findings may contribute to unravel the pathogenesis of CKD and to the development of innovative strategies to arrest its progression.NEW & NOTEWORTHY Hypoxia is regarded as a major pathogenic factor in chronic kidney disease (CKD). In disagreement with this view, we show here that sustained exposure to low ambient Po2 lessened kidney injury and inflammation in two CKD models: adenine (ADE) excess and chronic nitric oxide (NO) inhibition. Together with our previous findings in the remnant kidney, these observations indicate that local changes elicited by hypoxia may exert renoprotection in CKD, raising the prospect of novel therapeutic strategies for this disease.

Beneficiary Effects of Colchicine on Inflammation and Fibrosis in a Mouse Model of Kidney Injury.

INTRODUCTION: Low-grade inflammation is seen in many chronic illnesses, including chronic kidney disease (CKD). We have recently reported on beneficiary effects of anti-inflammatory treatment in the interleukin (IL-) 1 pathway on anemia as well as CKD extent in a mouse model. Colchicine has been shown to have beneficiary effects in several inflammatory conditions through various mechanisms, including inhibition of tubulin polymerization as well as caspase-1-mediated IL-1 activation. METHODS: Kidney injury (KI) was induced by administering an adenine diet to 8-week-old C57BL/6J mice treated with colchicine (Col) (30 µg/kg) or saline injections for 3 weeks, generating 4 groups: C, Ccol, KI, and KIcol. RESULTS: KI animals had an increase in inflammation indices in the blood (neutrophils), liver, and kidneys (uromodulin, IL-6, pSTAT3). Increased kidney tubulin polymerization and caspase-1 in KI, as well as kidney Mid88 and IRAK4 (downstream of IL-1), were inhibited in KIcol. Kidney macrophage and polymorphonuclear infiltration (positive for F4/80 and MPO, respectively), the percentage of fibrotic area, and TGFß mRNA levels were lower in KIcol versus KI. CONCLUSIONS: Colchicine inhibited tubulin polymerization and caspase-1 activation and attenuated kidney inflammation and fibrosis in a mouse model of adenine-induced KI. Given its reported safety profile for long-term anti-inflammatory therapy without increasing infection tendency, it may serve as novel therapeutic approach in CKD.

TIGAR Protects Against Adenine-Induced Ferroptosis in Human Proximal Tubular Epithelial Cells by Activating the mTOR/S6KP70 Axis.

TP53-induced glycolysis and apoptosis regulator (TIGAR) acts as a switch for nephropathy, but its underlying mechanism is still unclear. The purpose of this study was to explore the potential biological significance and underlying mechanism of TIGAR in modulating adenine-induced ferroptosis in human proximal tubular epithelial (HK-2) cells. HK-2 cells under- or overexpressing TIGAR were challenged with adenine to induce ferroptosis. The levels of reactive oxygen species (ROS), iron, malondialdehyde (MDA), and glutathione (GSH) were assayed. Expression of ferroptosis-associated solute carrier family seven-member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) at the level of mRNA and protein were measured by quantitative real-time-PCR and western blotting. The phosphorylation levels of proteins in the mTOR/S6KP70 pathway were determined by western blotting. Adenine overload triggered ferroptosis in HK-2 cells, as evidenced by reduced levels of GSH, SLC7A11, and GPX4, and increased levels of iron, MDA, and ROS. TIGAR overexpression repressed adenine-induced ferroptosis and induced mTOR/S6KP70 signaling. Inhibitors of mTOR and S6KP70 weakened the ability of TIGAR to inhibit adenine-induced ferroptosis. TIGAR inhibits adenine-induced ferroptosis in human proximal tubular epithelial cells by activating the mTOR/S6KP70 signaling pathway. Therefore, activating the TIGAR/mTOR/S6KP70 axis may be a treatment for crystal nephropathies.

Pyrophosphate as a novel anticoagulant for storage of whole blood: A proof-of-concept study.

BACKGROUND: Citrate is the only anticoagulant currently Food and Drug Administration (FDA)-approved for the long-term storage of blood for transfusion. Citrate inhibits phosphofructokinase and may play a pro-inflammatory role, suggesting that there may be an advantage to using alternative anticoagulants. Here, we examine the use of pyrophosphate as an anticoagulant. STUDY DESIGN AND METHODS: Whole blood samples from healthy donors were anticoagulated either with citrate-phosphate-adenine-dextrose (CPDA-1) or our novel anticoagulant mixture pyrophosphate-phosphate-adenine-dextrose (PPDA-1). Samples were assessed for coagulation capacity by thromboelastography immediately after anticoagulation (T0) with and without recalcification, as well as 5 hours after anticoagulation (T1) with recalcification. Complete blood counts were taken at both timepoints. Flow cytometry to evaluate platelet activation as well as blood smears to evaluate cellular morphology were performed at T1. RESULTS: No clotting was detected in samples anticoagulated with either solution without recalcification. After recalcification, clotting function was restored in both groups. R-Time in recalcified PPDA-1 samples was shorter than in CPDA-1 samples. A reduction in platelet count at T1 compared to T0 was observed in both groups. No significant platelet activation was observed in either group at T1. Blood smear indicated platelet clumping in PPDA-1. CONCLUSION: We have shown initial proof of concept that pyrophosphate functions as an anticoagulant at the dose used in this study, though there is an associated loss of platelets over time that may limit its usefulness for blood storage. Further dose optimization of pyrophosphate may limit or reduce the loss of platelets.

Citrate phosphate dextrose adenine (CPDA-1) can be sampled from blood collection bags in a multi-dose manner.

OBJECTIVE: To evaluate the sterility of citrate phosphate dextrose adenine (CPDA-1) anticoagulant when sampled from blood collection bags in a multi-dose manner. SAMPLE: 10 pre-filled CPDA-1 blood collection bags; 46 bacterial and 28 fungal culture result reports. PROCEDURES: 10 CPDA-1 blood collection bags were split into 2 equal groups and stored at either room temperature (24 °C) or refrigerator temperature (5 °C) for 30 days. Two bags in each group were designated as controls. Beginning on day 0 a 1.0 mL aliquot was withdrawn from each experimental bag and submitted for bacterial culture (aerobic and anaerobic) every 5 days, and fungal culture every 10 days. All 10 bags were sampled on day 30. Bacterial and fungal culture results were compiled and interpreted. RESULTS: 46 CPDA-1 aliquots were cultured, resulting in 2 positive microbial isolates: Bacillus was cultured from a previously unopened experimental bag on day 0, and Candida was cultured from a refrigerated experimental bag on day 30. Both positives are thought to represent post-sampling contamination, though these suspicions cannot be confirmed in the bag yielding Candida due to a lack of subsequent data. All other samples were negative for microbial growth. CLINICAL RELEVANCE: CPDA-1 blood collection bags stored at either 24 °C or 5 °C can be used in a multi-dose manner for up to 20 days when each sample is obtained aseptically. These results support the clinician's ability to utilize the contents of 1 bag multiple times rather than discarding the bag after a single use.

Roflumilast alleviates adenine-induced chronic kidney disease by regulating inflammatory biomarkers.

The present investigation was carried out to explore the role of roflumilast, a PDE4 inhibitor, as a potential treatment option for chronic kidney disease. Forty-six male Wistar rats were divided into five groups: Control, Disease control (50 mg/kg Adenine p.o.), Adenine + Roflumilast (0.5, 1 and 1.5 mg/kg, p.o.). Various urinary and serum biomarkers, antioxidant status, histopathology, and protein expression of inflammatory markers were measured to investigate the effects of roflumilast on kidney functions. Adenine was found to elevate the levels of serum creatinine, urea, uric acid, sodium, potassium, chloride, magnesium, and phosphorus and reduce the level of serum calcium. Further, adenine significantly increased the serum TGF-ß levels and reduced the anti-oxidant indices. Significant elevation was observed in protein expression of IL-1ß, TNF-α, MCP-1, ICAM-1, and Fibronectin. Histopathologically, adenine caused thickening of the glomerular basement membrane, inflammatory cells infiltration, atrophy, and glomeruli deterioration. However, Roflumilast administration (1 mg/kg) remarkably decrease serum creatinine, urea, uric acid, sodium, potassium, chloride, magnesium, phosphorus by 61%, 40%, 44%, 41%, 49%, 58%, 59% and 42% respectively, and increase in calcium by 158%. Moreover, Roflumilast (1 mg/kg) significantly reduced serum TGF-ß levels by 50% and elevated anti-oxidant indices by 257%, 112%, and 60%, respectively. The protein expression was significantly reduced by 5.5-fold, 7-fold, 5.7-fold, 6.2-fold, and 5.1-fold individually. Roflumilast noticeably improved the structure of glomeruli, tubules, and cellular functioning. The study confirmed that Roflumilast has the potential to ameliorate renal injury by reducing and regulating inflammatory responses.

Dietary Resveratrol Butyrate Monoester Supplement Improves Hypertension and Kidney Dysfunction in a Young Rat Chronic Kidney Disease Model.

Chronic kidney disease (CKD) remains a public health problem. Certain dietary supplements can assist in the prevention of CKD progression. In this regard, resveratrol is a polyphenol and has a potential therapeutic role in alleviating CKD. We previously utilized butyrate in order to improve the bioavailability of resveratrol via esterification and generated a resveratrol butyrate monoester (RBM). In this study, the hypothesis that RBM supplementation is able to protect against kidney dysfunction and hypertension was tested by using an adenine-induced CKD model. For this purpose, three-week-old male Sprague Dawley rats (n = 40) were equally categorized into: group 1-CN (sham control); group 2-CKD (adenine-fed rats); group 3-REV (CKD rats treated with 50 mg/L resveratrol); group 4-MEL (CKD rats treated with 25 mg/L RBM); and group 5-MEH (CKD rats treated with 50 mg/L RBM). At the end of a 12-week period, the rats were then euthanized. The adenine-fed rats displayed hypertension and kidney dysfunction, which were attenuated by dietary supplementation with RBM. The CKD-induced hypertension coincided with: decreased nitric oxide (NO) bioavailability; augmented renal protein expression of a (pro)renin receptor and angiotensin II type 1 receptor; and increased oxidative stress damage. Additionally, RBM and resveratrol supplementation shaped distinct gut microbiota profiles in the adenine-treated CKD rats. The positive effect of high-dose RBM was shown together with an increased abundance of the genera Duncaniella, Ligilactobacillus, and Monoglobus, as well as a decrease in Eubacterium and Schaedierella. Importantly, the mechanism of action of the RBM supplementation may be related to the restoration of NO, rebalancing of the RAS, a reduction in oxidative stress, and alterations to the gut microbiota. Moreover, RBM supplementation shows promise for the purposes of improving CKD outcomes and hypertension. As such, further translation to human studies is warranted.