Leishmaniasis, a neglected tropical disease caused by Leishmania parasites, continues to pose global health challenges. Current treatments face issues like resistance, safety, efficacy, and cost. This review covers the discovery, mechanisms of action, clinical applications, and limitations of key antileishmanial agents: pentavalent antimonials, amphotericin B, miltefosine, paromomycin, and pentamidine. Despite toxicity and resistance (antimonials), hospitalization needs and side effects (amphotericin B), regional efficacy variability (miltefosine), inconsistent outcomes (paromomycin), and severe side effects (pentamidine), these drugs are vital. Novel strategies to overcome the deficiencies of current therapies are highlighted, including combination regimens, advanced drug delivery systems, and immunomodulatory approaches. Comprehensive and cooperative efforts are crucial to fully realize the potential of advancements in antileishmanial pharmacotherapy and to reduce the unacceptable worldwide burden imposed by this neglected disease.
Zika virus has raised global concerns due to its link to microcephaly and Guillain–Barré syndrome in adults. One of viral nonstructural proteins-NS4B, an integral membrane protein, plays crucial roles in viral replication by interacting with both viral and host proteins, rendering it an attractive drug target for antiviral development. We purified the N-terminal region of ZIKV NS4B (NS4B NTD) and reconstituted it into detergent micelles. Here, we report the assignments of the backbone resonances of NS4B NTD in detergent micelles. The available assignment is useful for understanding its structure and ligand binding to provide useful information for developing NS4B inhibitors.
Mycobacterium tuberculosis, the pathogen of the deadly disease tuberculosis, depends on the redox cofactor mycofactocin (MFT) to adapt to and survive under hypoxic conditions. MftR is a TetR family transcription regulator that binds upstream of the MFT gene cluster and controls MFT synthesis. To elucidate the structural basis underlying MftR regulation, we determined the crystal structure of Mycobacterium tuberculosis MftR (TB-MftR). The structure revealed an interconnected hydrogen bond network in the α1-α2-α3 helices of helix-turn-helix (HTH) DNA-binding domain that is essential for nucleic acid interactions. The ligand-binding domain contains a hydrophobic cavity enclosing long-chain fatty acyl-CoAs like the key regulatory ligand oleoyl-CoA. Despite variations in ligand-binding modes, comparative analyses suggest regulatory mechanisms are largely conserved across TetR family acyl-CoA sensors. By elucidating the intricate structural mechanisms governing DNA and ligand binding by TB-MftR, our study enhances understanding of the regulatory roles of this transcription factor under hypoxic conditions, providing insights that could inform future research into Mycobacterium tuberculosis pathogenesis.
Stimulator of interferon genes(STING),also known as MITA,ERIS,MPYS or TMEM173,is a key player in innate immunity,specifically in the type Ⅰ interferon response[1-3].It is also involved in a range of non-canonical biological functions,including autophagy,cellular metabolism,translation,and DNA repair,and has implications in many diseases[4-9].After activation by its ligands,STING translocates from endoplasmic reticulum(ER),via ERGIC,Golgi apparatus and endosomes,finally to lysosomes for degradation[4-9].However,the mechanisms by which STING is delivered to lysosomes and whether this delivery process regulates STING activity remain elusive.
Recent studies have revealed that Porphyromonas gingivalis is closely related to the occurrence and progression of esophageal squamous cell carcinoma (ESCC). However, the underlying mechanism of P. gingivalis in ESCC has not been well elucidated. To explore the mechanism of P. gingivalis infection in ESCC, cellular proliferation, invasion, and migration models of KYSE-30 and KYSE-150 cells infected by P. gingivalis at a multiplicity of infection (MOI) of 10 were established. The results showed that P. gingivalis infection could drastically increase the proliferation, invasion, and migration ability of ESCC. Furthermore, the results of high-throughput sequencing showed that miR-194 was considerably upregulated in infected cells compared with control cells, which was further verified by qRT-PCR. The inhibition or overexpression of miR-194 had a significant effect on KYSE-30 and KYSE-150 cell migration and invasion. Additionally, the levels of GRHL3 and PTEN were decreased in P. gingivalis-infected esophageal cancer cells compared with uninfected esophageal cancer cells. Furthermore, dual-luciferase experiments confirmed that GRHL3 is a direct target of miR-194. In addition, the GRHL3-related pathway was investigated, and the levels of GRHL3 and PTEN were downregulated while the level of p-Akt was upregulated after P. gingivalis infection. Taken together, these findings indicated that P. gingivalis might promote ESCC proliferation and migration via the miR-194/GRHL3/PTEN/Akt signaling axis.
HUWE1, a HECT E3 ligase, is critical for processes like protein degradation and tumor development. Contrary to previous findings which suggested minimal non-covalent interactions between the HUWE1 HECT domain and ubiquitin, we identified a non-covalent interaction between the HUWE1 HECT N-lobe and ubiquitin using NMR spectroscopy, revealing a conserved ubiquitin-binding mode shared across HECT E3 ligases. Molecular dynamics simulations not only confirmed the stability of this interaction but also uncovered conformational changes in key residues, which likely influence binding affinity. Additionally, we highlighted the roles of both conserved and unique residues in ubiquitin binding. These findings advance our understanding of the interactions between the HUWE1 HECT domain and ubiquitin, and highlight potential targets for therapeutic intervention in the ubiquitin-proteasome pathway.
• Our results disclosed a dihelical structure of Enterovirus A71 3A 1–57 protein in apo form. • We depicted rigid helices and a unique flexible C-terminus for apo-form 3A 1–57 . • This study revealed a competitive binding-based molecular mechanism underlying inhibition of dimeric 3A by ER-DRI.
Supplementary Table from Anti-HIV Drug Elvitegravir Suppresses Cancer Metastasis via Increased Proteasomal Degradation of m6A Methyltransferase METTL3
Type 2 diabetes (T2DM) is a chronic metabolism disorder with a symptom as pancreatic β-cell dysfunction. In this study, the bioinformatics analysis identified the key regulators (PDX1 and miR-765) in T2DM. By qRT-PCR and western blotting, miR-765 with high expression and PDX1 with low expression were observed in blood samples from T2DM patients and the T2DM cell model. Together with GSIS assay, CCK-8, TUNEL assay, glycolysis assay, and mitochondrial respiration assay, miR-765 overexpression impaired insulin secretion cell viability, glycolysis, and mitochondrial respiration, while enhanced cell apoptosis in pancreatic β-cell. The Luciferase reporter, RIP, and RNA pull-down assays showed that PDX1 was the target gene of miR-765 in pancreatic β-cell. Besides, the negative effect of miR-765 on pancreatic β-cell could be overturned by PDX1 overexpression. In conclusion, we confirmed that miR-765 could cause a detrimental effect on pancreatic β-cell survival and function by targeting PDX1, which might provide new insight for T2DM therapy.
Due to antibiotic overuse, many bacteria have developed resistance, creating an urgent need for novel antimicrobial agents. It has been established that the filamentous temperature-sensitive mutant Z (FtsZ) of the bacterial cell division protein is an effective and promising antibacterial target. In this study, the optimal proteins were assessed by early recognition ability and the processed compound libraries were virtually screened using Vina. This effort resulted in the identification of 14 potentially active antimicrobial compounds. Among them, the compound T5S1607 demonstrated remarkable antibacterial efficacy against Bacillus subtilis ATCC9732 (MIC = 1 μg/mL) and Staphylococcus aureus ATC5C6538 (MIC = 4 μg/mL). Furthermore, in vitro experiments demonstrated that the selected compound T5S1607 rapidly killed bacteria and induced FtsZ protein aggregation, preventing bacterial division and leading to bacterial death. Additionally, cell toxicity and hemolysis experiments indicate that compound T5S1607 exhibits minimal toxicity to LO2 cells and shows no significant hemolytic effects on mammalian cells in vitro at the MIC concentration range. All the results indicate that compound T5S1607 is a promising antibacterial agent and a potential FtsZ inhibitor. In conclusion, this work successfully discovered FtsZ inhibitors with good activity through the virtual screening drug discovery process.
The type II restriction endonuclease Sau3AI cleaves the sequence 50-GATC-30 in double-strand DNA producing two sticky ends. Sau3AI cuts both DNA strands regardless of methylation status. Here, we report the crystal structures of the active site mutant Sau3AI-E64A and the C-terminal domain Sau3AI-C with a bound GATC substrate. Interestingly, the catalytic site of the N-terminal domain (Sau3AI-N) is spatially blocked by the C-terminal domain, suggesting a potential self-inhibition of the enzyme. Interruption of Sau3AI-C binding to substrate DNA disrupts Sau3AI function, suggesting a functional linkage between the N-and C-terminal domains. We propose that Sau3AI-C behaves as an allosteric effector binding one GATC substrate, which triggers a conformational change to open the N-terminal catalytic site, resulting in the subsequent GATC recognition by Sau3AI-N and cleavage of the second GATC site. Our data indicate that Sau3AI and UbaLAI might represent a new subclass of type IIE restriction enzymes.
Halogenated compounds are particularly important in pharmaceutical and agrochemical products. Biochemical halogenation with halogenases are environmental friendly reactions with high efficiency. Recently, the two new chlorinases (ClA1 and ClA2) were discovered from soil bacteria. However, the protein structure of ClA2 was not identified. Here, we determined the high-resolution crystal structure of ClA2. This structure will help us to understand the catalytic mechanism of chlorinase, and explain the catalytic process of the coupled chlorinase-fluorinase system, which offers the prospect of arising rapid radiolabeling protocols under mild conditions.
Pulsed-dye laser (PDL), as an effective and frequently-used treatment modality for infantile hemangiomas (IH), could render patients at risk of developing long-term alopecia. Data on alopecia caused by PDL treatment remain scant and the contributing factors are not clear. Our objective was to identify the risk factors associated with long-term alopecia resulting from PDL treatment for scalp IH. We conducted a retrospective study incorporating patients with IH diagnosis and PDL intervention via thoroughly reviewing the clinical database of the dermatology department. Scalp IH patients were further screened and their medical records were collected. Long-term alopecia was defined as no signs of terminal hair regrowth for at least 2 years in this study. Of the 1293 IH patients, 47 (14 boys and 33 girls) with a mean age of 4.5 months (standard deviation, 3.2) were diagnosed as scalp IH and had subsequently undergone PDL treatments. Hair growth in the treatment area of 18 patients (38.3%) nearly returned to normal, 22 patients (46.8%) had varying degrees of hair loss, and seven patients (14.9%) had no hair regrowth (long-term alopecia). Compared with the older patients receiving treatment, IH patients younger than 3 months who started PDL treatment had a higher risk of developing long-term alopecia (odds ratio, 30.833; 95% confidence interval, 4.079-232.025; p = 0.01). The total number of PDL sessions, post-treatment blisters, and location of IH were not shown to be significantly associated with the development of long-term alopecia. Collectively, our study provides an important insight into curating treatments for IH in infants younger than 3 months. PDL treatments for scalp IH may perhaps be avoided or delayed to prevent the development of treatment-associated long-term alopecia.
Background:Minimal invasive pulmonary resection in children is challenging, irrespective of whether it is conducted using a robot or a thoracoscope. This study presents the preliminary results of pediatric robotic pulmonary resection (RPR) and comparison outcomes with conventional thoracoscopic pulmonary resection (TPR).Methods:This is a retrospective study conducted in patients underwent RPR (RPR group; n=30) and TPR (TPR group; n=44). The clinical data, including operative time, post-operative body temperature, surgical complications, surgeon's workload (by NASA-TLX), postoperative hospital stay, and scar score (using the SCAR scale), of both the RPR and TPR groups were collected and compared.Results:Both groups had similar age and weight. The youngest patient belonged to the RPR group and was 6 months old and weighed 8 kg. One case in the RPR group and two in the TPR group were converted to thoracotomy. RPR had a longer total operative time (148.3±36.8 min), but a shorter pure operative time (103.9±28.5 min) than those of the TPR group [118.3±22.5 (P<0.001) and 111.4±18.3 min (P=0.045), respectively]. Compared to the TPR group, fewer patients in the RPR group reported fever postoperatively (2/29 vs. 11/42, P=0.039). The workload of the surgeons was also lower in the RPR group (55.2±4.7 vs. 62.9±6.0, P<0.01). No significant difference was observed in perioperative complications, drainage length, postoperative hospital stays, and scar score of the two groups.Conclusions:The safety and effectiveness of the robotic approach are similar to those of the thoracoscopic surgery for pediatric pulmonary resection in children heavier than 8 kg. In addition, the robotic approach shows improved operative dissection efficiency and accuracy for patients and reduced workload for surgeons. Hence, it is beneficial to both surgeons and patients.
The type II restriction endonuclease Sau3AI recognizes and cleaves the sequence 5′-GATC-3′ in double-strand DNA, producing two sticky ends. Sharing high sequence homology with the mismatch repair protein MutH, which recognizes the same GATC sequence, Sau3AI cuts both DNA strands regardless of methylation status, whereas MutH only nicks the unmethylated strand. Sau3AI appears to differ from MutH in domain organization and DNA cleavage mechanisms. Here, we report the novel crystal structures of an active site-mutated Sau3AI-E64A and C-terminal domain of (Sau3AI-C) complexed with a GATC substrate. Interestingly, the catalytic site of the N-terminal domain (Sau3AI-N) is spatially blocked by the C-terminal domain, suggesting potential self-inhibition within Sau3AI. Our data show that interruption of Sau3AI-C binding to substrate DNA disrupts Sau3AI function, suggesting a functional linkage between the N- and C-termini of Sau3AI. We propose that Sau3AI-C behaves as an allosteric effector to bind one GATC substrate and triggers a conformational change to open the N-terminal catalytic site, resulting in the subsequent GATC recognition by Sau3AI-N and cleavage of the second GATC site. Our data indicate that Sau3AI, together with the other monomeric enzyme UbaLAI, may represent a new subclass of type IIE restriction enzymes.
Carbon nanomaterials have huge application prospects in the fields of materials science and biomedicine. Graphene oxide (GO) can be served as an excellent carrier with good loading capacity and biocompatibility. However, lamelayers of GO are prone to aggregation and difficult to stably disperse in solution. Only relying on the mesh graphene sheets as a carrier still cannot achieve a good loading efficiency. Therefore, oriented layered graphene oxide pad (OGO) is synthesized and used as a carrier for ligand fishing. The structure of OGO exhibits good reproducibility and recyclability, and its regular open channels and low pore curvature can effectively ensure a high density of fishing sites and flow speed, improving the loading capacity and storage stability. According to the amount of immobilized cell membranes protein (CMP), OGO can reach 1.5 to 2 times loading capacity of GO. The established CMP@OGO is stable within 48 h at 4 ° C, and the reuse rate of OGO is 93.04 ± 0.67%. Finally, salvianolic acid B, deoxyshikonin, and shikonin were identified as potentially active compounds in comfrey combined with a high‐performance liquid chromatography‐hybrid linear ion trap/orbitrap mass spectrometer. It can provide a promising platform for OGO to screen active compounds in high throughput.
Asymptomatic transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a potential problem for pandemic control through public health strategies. Our results demonstrate that asymptomatic COVID-19 patients have better outcomes than symptomatic patients. This may have been due to more active cellular immune responses and normal liver function. Since asymptomatic patients have no clinical symptoms which can easily prevent timely diagnosis and treatment, they may cause a greater risk of virus transmission than symptomatic patients, which poses a major challenge to infection control. Evidence suggests that nonpharmaceutical public health interventions, like social distancing and face mask ordinances, play important roles in the control of COVID-19. Looking forward, it may be necessary to proceed cautiously while reopening businesses in areas of epidemicity to prevent potential waves of COVID-19 in the future.
Intracellular ribonucleotide (RN) and deoxyribonucleotide (dRN) pool sizes are critical for the fidelity of DNA synthesis. They are likely to be severely perturbed by many factors which disrupt the integrity and stability of DNA, leading to DNA damage. Exogenously supplied nucleosides are able to increase the deoxynucleoside triphosphate pools, then reverse the DNA damage, and decrease the oncogene-induced transformation dramatically. In this study, the impact of thymidine on the hydrogen peroxide (H2O2)-induced DNA damage was investigated in HepG2 liver cancer cells. From the result of the comet assay, the tail length of cells in the thymidine 600 μM + H2O2 1.0 mM group was dramatically decreased from 42.1 ± 10.8 to 21.9 ± 2.4 μm compared to that exposed with 1.0 mM H2O2 (p < 0.05), suggesting that pretreatment of thymidine reduced the DNA damage of HepG2 cells. Although the RN and dRN contents decreased in the damage group, most of them presented increasing tendency when pretreated with thymidine, especially the key metabolites dCTP, which was mainly related with the decline in the rate of DNA synthesis. The restoration also showed a significant G0/G1 phase arrest of cell cycle progression from 44.6 ± 2.2 to 56.6 ± 0.4% after pretreated with thymidine (p < 0.05). In conclusion, our data demonstrated that the pretreatment with thymidine had a potential protective ability against oxidative damage for DNA in HepG2 cells through the perturbation of RN and dRN pools as well as cell cycle arrest, which should provide new insights into the molecular basis of preventing H2O2-induced oxidative DNA damage in mammalian cells.
Schistosomula antigens play an important role in the growth and development of Schistosoma japonicum. We investigated the role of S. japonicum adenylate kinase 1 (SjAK1) in the growth and development of schistosomula. Quantitative real-time PCR showed that SjAK1 mRNA was expressed in all schistosomula stages, but increased gradually with the development of S. japonicum schistosomula. Using immunohistochemical techniques, the AK1 protein was found to be mainly distributed in the tegument and in some parenchymal tissues of the schistosomula. Double-stranded RNA-mediated knockdown of AK1 reduced AK1 mRNA transcripts by more than 90%; western blot analysis demonstrated that AK1 protein expression decreased by 66%. Scanning electron microscopy following RNA-mediated AK1 knockdown demonstrated that the sensory papillae degenerated significantly. Transmission electron microscopy demonstrated that the mean thickness of the tegument in the SjAK1 interference group was lower than that in the negative control group. Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) suggested that, compared with the negative control group, apoptosis increased in the interference group. These results show that AK1 may be involved in the growth and development of S. japonicum schistosomula, and thus may be a target when developing treatments for schistosomiasis.