Unraveling DDIT4 in the VDR-mTOR pathway: a novel target for drug discovery in diabetic kidney disease.

Introduction: Diabetic kidney disease (DKD) necessitates innovative therapeutic strategies. This study delves into the role of DNA damage-inducing transcription factor 4 (DDIT4) within the VDR-mTOR pathway, aiming to identify a novel target for DKD drug discovery. Methods: Transcriptome data from the Gene Expression Omnibus Database were analyzed to assess the expression of mTOR and VDR expression in human renal tissues. Clinical samples from DKD patients and minimal change disease (MCD) controls were examined, and a DKD animal model using 20-week-old db/db mice was established. DDIT4 plasmid transfection was employed to modulate the VDR-mTOR pathway, with its components evaluated using immunohistochemistry, real-time quantitative PCR (qRT-PCR), Western blotting, and enzyme-linked immunosorbent assay (ELISA). Results: Changes in the expression of the VDR-mTOR pathway were observed in both DKD patients and the animal model. Overexpression of DDIT4 increased VDR expression and decreased levels of mTOR, p70s6k, and 4E-BP1. Furthermore, DDIT4 treatment regulated autophagy by upregulating LC3I expression and downregulating LC3II expression. Notably, DDIT4 alleviated oxidative stress by reducing the levels of lipid peroxidation product MDA, while simultaneously increasing the levels of superoxide dismutase (SOD) and glutathione (GSH), underscoring the role of DDIT4 in the pathological process of DKD and its potential as a therapeutic target. Conclusion: Unraveling DDIT4's involvement in the VDR-mTOR pathway provides insights for innovative DKD drug discovery, emphasizing its potential as a therapeutic target for future interventions.

Nicotinamide mononucleotide ameliorates acute lung injury by inducing mitonuclear protein imbalance and activating the UPRmt.

Mitochondria need to interact with the nucleus under homeostasis and stress to maintain cellular demands and nuclear transcriptional programs. Disrupted mitonuclear interaction is involved in many disease processes. However, the role of mitonuclear signaling regulators in endotoxin-induced acute lung injury (ALI) remains unknown. Nicotinamide adenine dinucleotide (NAD+) is closely related to mitonuclear interaction with its central role in mitochondrial metabolism. In the current study, C57BL/6J mice were administrated with lipopolysaccharide 15 mg/kg to induce endotoxin-induced ALI and investigated whether the NAD+ precursor nicotinamide mononucleotide (NMN) could preserve mitonuclear interaction and alleviate ALI. After pretreatment with NMN for 7 days, NAD+ levels in the mitochondrial, nucleus, and total intracellular were significantly increased in endotoxemia mice. Moreover, supplementation of NMN alleviated lung pathologic injury, reduced ROS levels, increased MnSOD activities, mitigated mitochondrial dysfunction, ameliorated the defects in the nucleus morphology, and these cytoprotective effects were accompanied by preserving mitonuclear interaction (including mitonuclear protein imbalance and the mitochondrial unfolded protein response, UPRmt). Furthermore, NAD+-mediated mitonuclear protein imbalance and UPRmt are probably regulated by deacetylase Sirtuin1 (SIRT1). Taken together, our results indicated that NMN pretreatment ameliorated ALI by inducing mitonuclear protein imbalance and activating the UPRmt in an SIRT1-dependent manner.

Involvement of Nrf-2/HO-1 pathway in sevoflurane-induced cognitive improvement in rats with traumatic brain injury.

Traumatic brain injury (TBI) is an increasingly common emergency disease that usually leads to prolonged physical and cognitive impairments. In this study, we investigated if sevoflurane could induce cognitive improvement in TBI rats. Rats were subjected to head trauma induced by a fluid percussion device. A two-hour exposure to 3% sevoflurane was performed in a chamber immediately after TBI. Sevoflurane inhalation reduced the neurological and cognitive deficits induced by TBI with ameliorated synaptic injuries in the hippocampus. Moreover, after sevoflurane treatment, the expression of nuclear factor erythroid-2-related factor-2 (Nrf-2) and hemeoxygenase-1 (HO-1) in the hippocampus was enhanced 1 d after TBI and maintained at high levels 14 days later, and oxidative stress induced by TBI was inhibited. However, the HO-1 inhibitor, Zinc protoporphyrin (ZnPP), used to demonstrate the involvement of HO-1, suppressed the protective effect of sevoflurane. These results indicate that sevoflurane administered immediately after TBI may protect against TBI-induced synaptic and cognitive impairments by promoting the antioxidant Nrf-2/HO-1 pathway. Sevoflurane may be a promising anesthetic for patients with TBI.

Mast Cell Tryptase Promotes Inflammatory Bowel Disease-Induced Intestinal Fibrosis.

BACKGROUND: Intestinal fibrosis is the final pathological outcome of chronic intestinal inflammation without specific therapeutic drugs, which leads to ileus and surgical intervention. Intestinal fibrosis is characterized by excessive deposition of extracellular matrix (ECM). The role of mast cells (MCs), which are members of the sentinel immune cell population, is unknown in intestinal fibrosis. METHODS: In this study, we analyzed changes in MCs, tryptase proteins, and ECM components in human fibrotic and control patient intestines. We constructed dextran sodium sulfate-induced intestinal fibrosis models using wild-type mice, MC-reconstituted mice, and MC-deficient mice to explore the role of MCs and tryptase in intestinal fibrosis. The roles and mechanisms of MCs and tryptase on fibroblasts were evaluated using human MCs (HMC-1 and LAD-2), commercial tryptase proteins, human colon fibroblasts (CCD-18Co fibroblasts), the tryptase inhibitor APC366, and the protease-activated receptor-2 (PAR-2) antagonist ENMD-1068. RESULTS: Regardless of whether the colon was a human colon or a mouse colon, the fibrotic intestinal tissue had increased MC infiltration and a higher expression of ECM proteins or genes than that of the control group. The dextran sodium sulfate-induced intestinal fibrosis in MC-deficient mice was alleviated compared with that in wild-type mice. After MC reconstruction in MC-deficient mice, the alleviating effect disappeared. Tryptase, as a content stored in MC granules, was released into fibrotic intestinal tissues in the form of degranulation, resulting in an increased expression of tryptase. Compared with the control group, the tryptase inhibition group (the APC366 group) had reduced intestinal fibrosis. The CCD-18Co fibroblasts, when cocultured with MCs or treated with tryptase proteins, were activated to differentiate into myofibroblasts and secrete more ECM proteins (such as collagen and fibronectin). The underlying mechanism of fibroblast activation by tryptase was the activation of the PAR-2/Akt/mTOR pathway. CONCLUSIONS: We found that MC tryptase promotes inflammatory bowel disease-induced intestinal fibrosis. The underlying mechanism is that tryptase promotes the differentiation of fibroblasts into fibrotic-phenotype myofibroblasts by activating the PAR-2/Akt/ mTOR pathway of fibroblasts.

Circ_0000190 suppresses gastric cancer progression potentially via inhibiting miR-1252/PAK3 pathway.

BACKGROUND: Gastric cancer is a serious malignant tumor associated with aberrant circular RNAs (circRNAs) expression. In this study, we aim to investigate the role and the underlying mechanism of circ_0000190, a circRNA in gastric cancer. METHODS: Circ_0000190 expression in vivo was examined in gastric cancer and adjacent normal tissues by RT-PCR. Circ_0000190 expression in gastric cancer cell lines was detected by FISH and RT-PCR. The role of the circRNA in gastric cancer cells was assessed by the analysis of cell viability, apoptosis, proliferation, cell cycle and migration. The potential effector of circ_0000190 was predicted by computational screen and validated by luciferase reporter assay. Furthermore, Mice model of human gastric cancer was established to observe the underlying mechanisms of circ_0000190. RESULTS: Circ_0000190 was down-regulated in gastric cancer tissues and cells, with a major location in cytoplasm. Circ_0000190 inhibited gastric cancer cell viability, proliferation and migration, and induced apoptosis and cell cycle arrest by regulating the expression of capase-3, p27 and cyclin D. In addition, the circRNA was validated as a sponge of miR-1252, which directly targeted PAK3. The effects of circ_0000190 on the cellular processes were blocked by miR-1252 mimics, which could be rescued after further overexpression of PAK3. CONCLUSIONS: Circ_0000190 suppresses gastric cancer progression potentially via inhibiting miR-1252/PAK3 pathway, employing circ_0000190 might be a promising therapeutic strategy for the treatment of gastric cancer.

Electroacupuncture Improves Cognition in Rats With Sepsis-Associated Encephalopathy.

BACKGROUND: Sepsis-associated encephalopathy (SAE) is a common complication of sepsis. Although sepsis is effectively managed with the administration of antibiotics and source control, which may include surgical intervention, SAE usually leads to prolonged cognitive dysfunction affecting the quality of life of the patients. In this study, we investigated the possible effect of electroacupuncture (EA) on cognition in a model of SAE induced by cecal ligation and puncture (CLP). MATERIALS AND METHODS: The rats were randomly divided into four groups: the control group, the CLP group, the CLP with EA treatment group (CLP + EA), and the CLP with sham EA treatment group (CLP + sham EA). EA at DU20, LI11, and ST36 or sham EA was performed 30 min daily for 10 consecutive days starting from 2 days before CLP. Then cognitive function was examined by the Morris water maze test. On day 14 after CLP surgery, the synaptic injury, neuron loss, and oxidative stress were studied. RESULTS: Rats with EA treatment showed improved survival rate, spatial learning, and memory abilities. The dendritic spine density, the synaptic proteins, and the hippocampal neuron number were also increased after EA treatment. Furthermore, EA suppressed oxidative stress through regulating the level of malondialdehyde and superoxide dismutase and enhanced the expression of antioxidant nuclear factor erythroid-2-related factor-2 and hemeoxygenase-1. But sham EA did not have the same effect. CONCLUSIONS: EA may protect against SAE-induced cognitive dysfunction by inhibiting synaptic injury, neuronal loss, and oxidative stress, and the nuclear factor erythroid-2-related factor-2/hemeoxygenase-1 signaling pathway may be involved in this effect.

Effects of adding tripterygium glycosides to angiotensin-converting enzyme inhibitors or angiotensin receptor blockers on albuminuria in patients with diabetic nephropathy.

INTRODUCTION: Tripterygium glycosides (TGs) have been widely used in China to treat diabetic nephropathy (DN); however, proof of their use is scarce. The present study aimed to evaluate the effectiveness and safety of adding TGs to angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs). METHODS: By searching Embase, MEDLINE, Cochrane Library, SINOMED, China National Knowledge Infrastructure, VIP Information/Chinese Scientific Journals, and WANFANG databases, we identified previous studies that met the specific selection criteria and included them in the meta-analysis. Analyses were performed using Review Manager (version 5.3). RESULTS: Nine randomized controlled trials were included in the final meta-analysis. Patients were compared before and after treatment with ACE inhibitors or ARBs plus TGs, or ACE inhibitors or ARBs alone. The results revealed that treatment with ACE inhibitors or ARBs plus TGs resulted in significantly greater reductions in 24-h urinary total protein (UTP) levels (trial duration <2 months, mean difference [MD]: -0.25; 95% confidence interval [CI]: -0.32, -0.18; trial duration between 2 and 6 months, MD: -0.39; 95% CI: -0.44, -0.33; trial duration >6 months, MD: -2.09; 95% CI: -2.89, -1.29) compared with treatment using ACE inhibitors or ARBs alone. Additionally, ACE inhibitors or ARBs plus TGs showed better results after long-term administration. Treatment with ACE inhibitors or ARBs plus TGs resulted in significantly greater reductions in serum creatinine (SCr) compared with ACE inhibitors or ARBs alone (MD: -9.87; 95% CI: -13.76, -5.97). CONCLUSION: In patients with DN, adding TGs to ACE inhibitors or ARBs significantly lowered both the 24-h UTP and SCr levels. Therefore, ACE inhibitors or ARBs plus TGs might improve the treatment of DN in patients.

Targeting HMGB1 ameliorates cardiac fibrosis through restoring TLR2-mediated autophagy suppression in myocardial fibroblasts.

BACKGROUND: Extracellular high-mobility group box 1 (HMGB1) has been identified as playing a critical role in the pathogenesis of tissue fibrosis. However, the underlying mechanism of its involvement in cardiac fibrosis is still not well-defined. Here, we aim to investigate whether toll-like receptor 2 (TLR2) contributes to the extracellular HMGB1-mediated development and progression of cardiac fibrosis. METHODS: A mouse model of cardiac fibrosis was induced by subcutaneous injection of isoproterenol (ISO). Glycyrrhizic acid (GA), an inhibitor of HMGB1 derived from natural products, was simultaneously administered by intraperitoneal injection. Echocardiography, H&E and Sirius red staining were used to evaluate cardiac function and fibrosis. The myocardial expression of autophagy-associated proteins was examined using immunoblotting. Cardiac fibroblasts were treated with different concentrations of HMGB1 to examine the expression levels of α-SMA, collagen I and autophagy markers. Interactions of HMGB1/TLR2 and α-SMA/p62 were examined by immunoprecipitation and immunofluorescence. RESULTS: ISO-treated mice showed characteristic cardiac fibrosis, increased expression and co-localization of HMGB1 and TLR2, as well as impaired autophagic signals in myocardial tissues, which could be prevented by silencing TLR2. Exogenous administration of HMGB1 blocked the autophagic flux in fibroblasts, which caused extensive accumulation of collagen I and α-SMA. In addition, cardiac fibrosis was alleviated by GA treatment through abrogating the interaction between HMGB1 and TLR2. CONCLUSIONS: Our study suggests that the interaction between TLR2 and HMGB1 contributes to the pathogenesis of cardiac fibrosis via suppressing fibroblast autophagy, and that inhibiting HMGB1 with GA provides therapeutic benefits for the treatment of fibroproliferative heart diseases.

Identification of two novel mutations in the ATP7B gene that cause Wilson's disease.

BACKGROUND: Wilson's disease is an autosomal recessive disorder characterized by liver disease and/or neurologic deficits due to copper accumulation and is caused by pathogenic mutations in the ATP7B gene. DATA SOURCES: Two unrelated Chinese patients born to nonconsanguineous parents who were diagnosed with earlyonset Wilson's disease. DNA sequencing and bioinformation analysis were conducted. RESULTS: We have identified four mutations in two family trios, of which two were novel, namely, c. 3028A>G (p. K1010E) and c.3992T>G (p.Y1331X), in each patient. CONCLUSIONS: Gene testing is playing an important role in diagnosis of Wilson's disease. The early-onset of Wilson's disease is apparently not associated with P-ATPase domain in the ATP7B protein. Our findings further widen the spectrum of mutations involving the ATP7B gene.