Cornus officinalis var. koreana Kitam extracts alleviate cadmium-induced renal fibrosis by targeting matrix metallopeptidase 9.

ETHNOPHARMACOLOGICAL RELEVANCE: Cornus officinalis var. koreana Kitam (Cornus officinalis) is a commonly used Chinese herbal medicine and has a good clinical efficacy in kidney and liver diseases. Recent years, a number of studies reported the significant effects of Cornus officinalis on renal fibrosis. However, it is still unclear about the underlying specific mechanism, the bioactive ingredients, and the target gene regulatory network. AIM OF THE STUDY: We investigated the impact of Cornus officinalis extract on cadmium-induced renal fibrosis, screened the bioactive ingredients of Cornus officinalis using a pharmacological sub-network analysis, and explored the regulatory effects of Cornus officinalis extracts on target gene matrix metallopeptidase 9 (MMP9). METHODS: Male C57BL/6N mice were treated with single or combinatorial agents such as saline, cadmium chloride, Cornus officinalis, Isoginkgetin and FSL-1. Isoginkgetin is a compound with anti-MMP9 activity. FSL-1 can induce MMP9 expression. Masson staining and Western blot and immunohistochemistry analyses were used for assessing renal fibrosis. In addition, wound healing model was established using BUMPT (Boston university mouse proximal tubular) cells to investigate how Cornus officinalis affected cadmium-induced cell migration. The main Cornus officinalis bioactive compounds were identified by UHPLC-MS (Ultra-high-performance liquid chromatography - mass spectrometry). The MMP9 target for Cornus officinalis active ingredients were confirmed through a pharmacological sub-network analysis. RESULTS: Aqueous extracts of Cornus officinalis protected from renal dysfunction and kidney fibrosis induced by cadmium chloride in mice. In vitro experiments validated that Cornus officinalis extracts inhibited cell migration ability especially in cadmium chloride condition. The sub-network analysis and chemical components profiling technique revealed the active compounds of Cornus officinalis. Cellular thermal shift assay verified the binding abilities of three active components Daidzein, N-Acetyl-L-tyrosine or Swertisin with matrix metalloproteinase-9. Gelatin zymography assay revealed that the activity of MMP9 was inhibited by the three active components. We further confirmed that MMP9 was involved in the process of Cornus officinalis extracts reducing renal fibrosis. Cornus officinalis attenuated the cadmium-induced renal fibrosis was correlated with decreased expression of MMP9, collagen I, α-SMA (alpha-smooth muscle actin) and vimentin. CONCLUSIONS: This study demonstrated that Cornus officinalis extracts could alleviate the cadmium chloride-induced renal fibrosis by targeting MMP9, and might provide new insights into the mechanism of treating renal fibrosis by Cornus officinalis.

Tim-3 deficiency aggravates cadmium nephrotoxicity via regulation of NF-κB signaling and mitochondrial damage.

Kidney is the target organ of serious cadmium injury. Kidney damage caused by cadmium exposure is greatly influenced by the inflammatory response and mitochondrial damage. T cell immunoglobulin domain and mucin domain 3 (Tim-3) is an essential protein that functions as a negative immunological checkpoint to regulate inflammatory responses. Mice were given cadmium treatments at various dosages (0, 1.5, 3, 4.5 mg/kg) and times (0, 3, 5, 7 days) to assess the effects of cadmium on kidney damage. We found that the optimal way to induce kidney injury in mice was to inject 4.5 mg/kg of cadmium intraperitoneally for five days. It is interesting that giving mice 4.5 mg/kg of cadmium intravenously for seven days drastically lowered their survival rate. After cadmium exposure, Tim-3 knockout mice exhibited higher blood concentrations of urea nitrogen and creatinine compared to control mice. Tim-3 impacted the expression of oxidative stress-associated genes such as UDP glucuronosyltransferase family 1 member A9 (Ugt1a9), oxidative stress-induced growth inhibitor 2 (Osgin2), and S100 calcium binding protein A8 (S100a8), according to RNA-seq and real-time RT-PCR data. Tim-3 deficiency also resulted in activated nuclear factor-kappa B (NF-κB) signaling pathway. The NF-κB inhibitor 2-[(aminocarbonyl)amino]-5-(4-fluorophenyl)-3-thiophenecarboxamide (TPCA-1) significantly alleviated cell apoptosis, oxidative stress response, and renal tubule inflammation in Tim-3 knockout mice exposed to cadmium. Furthermore, cadmium caused obvious B-cell lymphoma protein 2 (Bcl-2)-associated X (Bax) translocation from cytoplasm to mitochondria, which can be inhibited by TPCA-1. In conclusion, Tim-3 prevented mitochondrial damage and NF-κB signaling activation, hence providing protection against cadmium nephrotoxicity.

The efficacy and safety of remdesivir alone and in combination with other drugs for the treatment of COVID-19: a systematic review and meta-analysis.

BACKGROUND: Remdesivir is considered to be a specific drug for treating coronavirus disease 2019. This systematic review aims to evaluate the clinical efficacy and risk of remdesivir alone and in combination with other drugs. RESEARCH DESIGN AND METHODS: The PubMed, Embase, SCIE, Cochrane Library, and American Clinical trial Center databases were searched up to 1 April 2022 to identify. Randomized controlled trials (RCTs) and observational studies comparing the efficacy of remdesivir monotherapy and combination therapy with that of control drugs. RESULTS: Ten RCTs and 32 observational studies were included in the analysis. Regarding the primary outcome, remdesivir use reduced mortality in patients with severe COVID-19 (RR = 0.57, 95% CI (0.48,0.68)) and shortened the time to clinical improvement (MD = -2.51, 95% CI (-2.75, -2.28)). Regarding other clinical outcomes, remdesivir use was associated with improved clinical status (RR = 1.08, 95%CI (1.01, 1.17)). Regarding safety outcomes, remdesivir use did not cause liver or kidney damage (RR = 0.87, 95%CI (0.68, 1.11)) (RR = 0.88, 95%CI (0.70,1.10)). Compared with remdesivir alone, remdesivir combined with other drugs (e.g., steroids, favipiravir, and convalescent plasma) had no effect on mortality. CONCLUSION: The use of remdesivir can help to reduce the mortality of patients with severe COVID-19 and shorten the time to clinical improvement. There was no benefit of remdesivir combination therapy for other clinical outcomes. TRIAL REGISTRATION: PROSPERO registration number: CRD42022322859.

Tim-3 protects against cisplatin nephrotoxicity by inhibiting NF-κB-mediated inflammation.

The impact of Tim-3 (T cell immunoglobulin and mucin domain-containing protein 3) on cisplatin-induced acute kidney injury was investigated in this study. Cisplatin-induced Tim-3 expression in mice kidney tissues and proximal tubule-derived BUMPT cells in a time-dependent manner. Compared with wild-type mice, Tim-3 knockout mice have higher levels of serum creatinine and urea nitrogen, enhanced TUNEL staining signals, more severe 8-OHdG (8-hydroxy-2' -deoxyguanosine) accumulation, and increased cleavage of caspase 3. The purified soluble Tim-3 (sTim-3) protein was used to intervene in cisplatin-stimulated BUMPT cells by competitively binding to the Tim-3 ligand. sTim-3 obviously increased the cisplatin-induced cell apoptosis. Under cisplatin treatment conditions, Tim-3 knockout or sTim-3 promoted the expression of TNF-α (tumor necrosis factor-alpha) and IL-1ß (Interleukin-1 beta) and inhibited the expression of IL-10 (interleukin-10). NF-κB (nuclear factor kappa light chain enhancer of activated B cells) P65 inhibitor PDTC or TPCA1 lowed the increased levels of creatinine and BUN (blood urea nitrogen) in cisplatin-treated Tim-3 knockout mice serum and the increased cleavage of caspase 3 in sTim-3 and cisplatin-treated BUMPT cells. Moreover, sTim-3 enhanced mitochondrial oxidative stress in cisplatin-induced BUMPT cells, which can be mitigated by PDTC. These data indicate that Tim-3 may protect against renal injury by inhibiting NF-κB-mediated inflammation and oxidative stress.

Electrochemiluminescent (ECL) biosensor for Burkholderia pseudomallei based on cobalt-doped MOF decorated with gold nanoparticles and N-(4-aminobutyl)-N-(ethylisoluminol).

A multifunctional catalytic nanomaterial (Co-MOF@AuNP@ABEI) composed of cobalt-doped metal-organic frameworks (Co-MOF), gold nanoparticles (AuNP), and N-(4-aminobutyl)-N-(ethylisoluminol) (ABEI) is reported. Co-MOF@AuNP@ABEI exhibits high synergistic and zero-distance catalytic properties, which are beneficial to the improvement of the detection sensitivity of an electrochemiluminescent (ECL) biosensor. After coupling with the ECL system and 3D magnetic walking nanomachine amplification strategy, the Co-MOF@AuNP@ABEI can achieve an ultrasensitive ECL assay of Burkholderia pseudomallei with the limit of detection (LOD) of 60.3 aM, which is 2 and 4 orders of magnitude lower than individual ECL system without the nanomachine (4.97 fM) and individual walking nanomachine (340 fM), and superior to the pathogenic bacteria analyses in the previous report. Moreover, the LOD of the proposed ECL detection system for the determination of B. pseudomallei in serum sample was as low as 9.0 CFU mL-1. The relative standard deviations (RSD) of ECL intensity for the detection of five B. pseudomallei-spiked serum samples were 4.02%, 0.84%, 0.84%, 1.55%, and 0.21%, respectively. The recoveries of the ECL biosensor for the detection of B. pseudomallei DNA-spiked serum samples were 93.63 ~ 107.83%. Therefore, this work demonstrated that the developed multifunctional catalytic nanomaterial with synergistic and zero-distance catalytic properties can be used as excellent ECL signal reporter to improve the detection sensitivity of ECL biosensor.

A novel lytic phage potentially effective for phage therapy against Burkholderia pseudomallei in the tropics.

BACKGROUND: Burkholderia pseudomallei is a tropical pathogen that causes melioidosis. Its intrinsic drug-resistance is a leading cause of treatment failure, and the few available antibiotics require prolonged use to be effective. This study aimed to assess the clinical potential of B. pseudomallei phages isolated from Hainan, China. METHODS: Burkholderia pseudomallei strain (HNBP001) was used as the isolation host, and phages were recovered from domestic environmental sources, which were submitted to the host range determination, lytic property assays, and stability tests. The best candidate was examined via the transmission electron microscope for classification. With its genome sequenced and analyzed, its protective efficacy against B. pseudomallei infection in A549 cells and Caenorhabditis elegans was evaluated, in which cell viability and survival rates were compared using the one-way ANOVA method and the log-rank test. RESULTS: A phage able to lyse 24/25 clinical isolates was recovered. It was classified in the Podoviridae family and was found to be amenable to propagation. Under the optimal multiplicity of infection (MOI) of 0.1, an eclipse period of around 20 min and a high titer (1012 PFU/ml) produced within 1 h were demonstrated. This phage was found stabile at a wide range of temperatures (24, 37, 40, 50, and 60 °C) and pH values (3-12). After being designated as vB_BpP_HN01, it was fully sequenced, and the 71,398 bp linear genome, containing 93 open reading frames and a tRNA-Asn, displayed a low sequence similarity with known viruses. Additionally, protective effects of applications of vB_BpP_HN01 (MOI = 0.1 and MOI = 1) alone or in combination with antibiotics were found to improve viability of infected cells (70.6 ± 6.8%, 85.8 ± 5.7%, 91.9 ± 1.8%, and 96.8 ± 1.8%, respectively). A significantly reduced mortality (10%) and a decreased pathogen load were demonstrated in infected C. elegans following the addition of this phage. CONCLUSIONS: As the first B. pseudomallei phage was isolated in Hainan, China, phage vB_BpP_HN01 was characterized by promising lytic property, stability, and efficiency of bacterial elimination during the in vitro/vivo experiments. Therefore, we can conclude that it is a potential alternative agent for combating melioidosis.

Crystal Structures of the C-Glycosyltransferase UGT708C1 from Buckwheat Provide Insights into the Mechanism of C-Glycosylation.

C-Glycosyltransferases (CGTs) catalyze the formation of C-glycosidic bonds for the biosynthesis of C-glycosides, but the underlying mechanism is unclear. This process improves the solubility and bioavailability of specialized metabolites, which play important roles in plant growth and development and represent rich resources for drug discovery. Here, we performed functional and structural studies of the CGT UGT708C1 from buckwheat (Fagopyrum esculentum). Enzymatic analysis showed that UGT708C1 is capable of utilizing both UDP-galactose and UDP-glucose as sugar donors. Our structural studies of UGT708C1 complexed with UDP-glucose and UDP identified the key roles of Asp382, Gln383, Thr151, and Thr150 in recognizing the sugar moiety of the donor substrate and Phe130, Tyr102, and Phe198 in binding and stabilizing the acceptor. A systematic site-directed mutagenesis study confirmed the important roles of these residues. Further structural analysis combined with molecular dynamics simulations revealed that phloretin binds to the acceptor binding pocket in a bent state with a precise spatial disposition and complementarity. These findings provide insights into a catalytic mechanism for CGTs.

Expression, purification and oligomerization of the S-adenosylmethionine transporter.

The S-adenosylmethionine carrier (SAMC) is a membrane transport protein located on the inner membrane of mitochondria that catalyzes the import of S-adenosylmethionine (SAM) into the mitochondrial matrix. SAMC mutations can cause a series of mitochondrial defects, including those affecting RNA stability, protein modification, mitochondrial translation and biosynthesis. Here, we describe the expression, purification and oligomerization of SAMC. The SAMC genes from three species were cloned into a eukaryotic expression vector with a GFP tag, and confocal microscopy analysis showed that these SAMCs were localized to mitochondria. A BacMam expression system was used for the expression of D. rerio SAMC with a FLAG tag. A size-exclusion chromatography analysis showed that SAMC may form a hexamer. A negative-staining electron microscopy analysis showed that SAMC formed tiny uniform particles and also confirmed the oligomerization of SAMC.

Synthesis of a Fluoromethacrylate Hydroxystyrene Block Copolymer Capable of Rapidly Forming Sub-5 nm Domains at Low Temperatures.

A series of poly(pentadecafluorooctyl methacrylate)-block-polyhydroxystyrene (PPDFMA-b-PHS) block copolymers (BCPs) were synthesized via reversible addition-fragmentation chain-transfer polymerization and subsequent deprotection. Because of the high incompatibility between hydroxyl groups and fluoro groups, the interaction parameter (χ) of these BCPs, determined by temperature-resolved small-angle X-ray scattering (SAXS), was extremely high. The χ value of PPDFMA-b-PHS was 0.48 at 150 °C, 16× larger than the χ of polystyrene-block-poly(methyl methacrylate). The microphase behavior of PPDFMA-b-PHS with various volume fractions of PHS block was determined by SAXS, yielding ordered lamellar morphologies with different sizes of domain spacing (d), and further confirmed by transmission electron microscopy. The minimum d obtained was 9.8 nm annealed at a mild temperature for a short time (80 °C for 1 min) by SAXS analysis, indicating the width of each lamellar domains was <5 nm.