Influence of anti-thymocyte globulin plasma levels on outcome parameters in stem cell transplanted children

IntroductionAllogenic hematopoietic stem cell transplantation is a curative option for malignant and non-malignant pediatric diseases. Serotherapy is often employed to avoid graft-versus-host disease (GvHD) on one hand and graft rejection on the other hand. Therapeutic drug monitoring is increasingly used to allow for more precise dosing especially in pediatric patients due to their specific pharmacological characteristics. Application of T-cell directed antibodies is not routinely monitored, but may benefit from more precise dosing regimens.MethodsTwo different preparations of rabbit anti-thymocyte globulin (rATG), Thymoglobuline® and ATG-F (Grafalon®), are frequently used to prevent GvHD in pediatric patients by in vivo T-cell depletion. Total rATG levels and active rATG levels were analyzed prospectively in pediatric patients undergoing HSCT. Clinical and laboratory outcome parameters were recorded.ResultsrATG levels were measured in 32 patients, 22 received thymoglobuline and 10 received ATG-F. The median total peak plasma level was 419.0 µg/ml for ATG-F and 60.4 µg/ml for thymoglobuline. For ATG-F, exposure could be predicted from the calculated dose more precisely than for thymoglobuline. Active peak plasma levels neither of ATG-F, nor of thymoglobuline correlated significantly with the number of lymphocytes prior to serotherapy. There was no significant difference in incidence of aGvHD, cGvHD, rejection, mixed chimerism or viral infections in the two cohorts. However, in our cohort, patients with high thymoglobuline exposure showed a compromised reconstitution of T cells.ConclusionsATG-F and thymoglobuline show different pharmacological and immunological impact in children, whose clinical significance needs to be investigated in larger cohorts.     

Can maternal exposure to paracetamol impair reproductive parameters of male rat offspring?

Paracetamol is a widely used medication during gestation and lactation periods for the treatment of pain and fever. Several studies have shown that exposure to paracetamol can increase the incidence of cryptorchidism and decrease testosterone production. Therefore, the present study aimed to evaluate if maternal treatment with paracetamol during gestation and gestation/lactation periods can alter reproductive and behavioral parameters in male offspring. Female Wistar rats were treated daily by gavage with water or paracetamol (350 mg/kg/day) during gestation (CTRG and PARG) or gestation/lactation periods (CTRGL and PARGL). There were significant differences in histomorphometry (increased volume and total length of the seminiferous tubules) and weight of testes (PARG group) and copulatory behavior and testosterone levels (PARG and PARGL groups) at PND 120. Therefore, the present study showed that maternal exposure to paracetamol has an impact on the reproductive system and sexual behavior of male adult offspring suggesting an impaired in sexual hypothalamic differentiation at the beginning of the development of the brain.     

Molecular Dynamics Simulation to Uncover the Mechanisms of Protein Instability During Freezing

Freezing is a common process applied in the pharmaceutical industry to store and transport biotherapeutics. Herewith, multi-scale molecular dynamics simulations of Lactate dehydrogenase (LDH) protein in phosphate buffer with/without ice formation performed to uncover the still poorly understood mechanisms and molecular details of protein destabilization upon freezing. Both fast and slow ice growing conditions were simulated at 243 K from one or two-side of the simulation box, respectively. The rate of ice formation at all-atom simulations was crucial to LDH stability, as faster freezing rates resulted in enhanced structural stability maintained by a higher number of intramolecular hydrogen bonds, less flexible protein's residues, lower solvent accessibility and greater structural compactness. Further, protein aggregation investigated by coarse-grained simulations was verified to be initiated by extended protein structures and retained by electrostatic interactions of the salt bridges between charged residues and hydrogen bonds between polar residues of the protein. Lastly, the study of free energy of dissociation through steered molecular dynamics simulation revealed LDH was destabilized by the solvation of the hydrophobic core and the loss of hydrophobic interactions. For the first time, experimentally validated molecular simulations revealed the detailed mechanisms of LDH destabilization upon ice formation and cryoconcentration of solutes.     

Chemo-photothermal immunotherapy for eradication of orthotopic tumors and inhibition of metastasis by intratumoral injection of polydopamine versatile hydrogels

Cancer remains one of the leading causes of death globally and metastasis always leads to treatment failure. Here, we develop a versatile hydrogel loading photothermal agents, chemotherapeutics, and immune-adjuvants to eradicate orthotopic tumors and inhibit metastasis by combinational therapy. Hydrogel networks were synthesized via the thiol-Michael addition of polydopamine (PDA) with thiolated hyaluronic acid. PDA acted as a cross-linking agent and endowed the hydrogel with excellent photothermal property. Meanwhile, a chemotherapeutic agent, doxorubicin (DOX), was loaded in the hydrogel via π?π stacking with PDA and an immune-adjuvant, CpG-ODN, was loaded via electrostatic interaction. The release of DOX from the hydrogel was initially slow but accelerated due to near infrared light irradiation. The hydrogels showed remarkably synergistic effect against 4T1 cancer cells and stimulated plenty of cytokines secreting from RAW264.7 cells. Moreover, the hydrogels eradicated orthotopic murine breast cancer xenografts and strongly inhibited metastasis after intratumoral injection and light irradiation. The high anticancer efficiency of this chemo-photothermal immunotherapy resulted from the strong synergistic effect of the versatile hydrogels, including the evoked host immune response. The combinational strategy of chemo-photothermal immunotherapy is promising for highly effective treatment of breast cancer.     

Synergistic antitumor activity of artesunate and HDAC inhibitors through elevating heme synthesis via synergistic upregulation of ALAS1 expression

Artemisinin and its derivatives (ARTs) were reported to display heme-dependent antitumor activity. On the other hand, histone deacetylase inhibitors (HDACi) were known to be able to promote heme synthesis in erythroid cells. Nevertheless, the effect of HDACi on heme homeostasis in non-erythrocytes remains unknown. We envisioned that the combination of HDACi and artesunate (ARS) might have synergistic antitumor activity through modulating heme synthesis. In vitro studies revealed that combination of ARS and HDACi exerted synergistic tumor inhibition by inducing cell death. Moreover, this combination exhibited more effective antitumor activity than either ARS or HDACi monotherapy in xenograft models without apparent toxicity. Importantly, mechanistic studies revealed that HDACi coordinated with ARS to increase 5-aminolevulinate synthase (ALAS1) expression, and subsequent heme production, leading to enhanced cytotoxicity of ARS. Notably, knocking down ALAS1 significantly blunted the synergistic effect of ARS and HDACi on tumor inhibition, indicating a critical role of ALAS1 upregulation in mediating ARS cytotoxicity. Collectively, our study revealed the mechanism of synergistic antitumor action of ARS and HDACi. This finding indicates that modulation of heme synthesis pathway by the combination based on ARTs and other heme synthesis modulators represents a promising therapeutic approach to solid tumors.     

Discovery of the anti-angiogenesis effect of eltrombopag in breast cancer through targeting of HuR protein

HuR (human antigen R), an mRNA-binding protein responsible for poor prognosis in nearly all kinds of malignancies, is a potential anti-tumor target for drug development. While screening HuR inhibitors with a fluorescence polarization (FP) based high-throughput screening (HTS) system, the clinically used drug eltrombopag was identified. Activity of eltrombopag on molecular level was verified with FP, electrophoretic mobility shift assay (EMSA), simulation docking and surface plasmon resonance (SPR). Further, we showed that eltrombopag inhibited in vitro cell proliferation of multiple cancer cell lines and macrophages, and the in vivo anti-tumor activity was also demonstrated in a 4T1 tumor-bearing mouse model. The in vivo data showed that eltrombopag was efficient in reducing microvessels in tumor tissues. We then confirmed the HuR-dependent anti-angiogenesis effect of eltrombopag in 4T1 cells and RAW264.7 macrophages with qRT-PCR, HuR-overexpression and HuR-silencing assays, RNA stability assays, RNA immunoprecipitation and luciferase assays. Finally, we analyzed the in vitro anti-angiogenesis effect of eltrombopag on human umbilical vein endothelial cells (HUVECs) mediated by macrophages with cell scratch assay and in vitro Matrigel angiogenesis assay. With these data, we revealed the HuR-dependent anti-angiogenesis effect of eltrombopag in breast tumor, suggesting that the existing drug eltrombopag may be used as an anti-cancer drug.     

Mitochondrial-targeted nanoparticles: Delivery and therapeutic agents in cancer

Antitumor agents are delivered via nanoparticles (NPs) to the mitochondria. The drugs attack the mitochondria resulting in mitochondrial damage and the release of cytochrome C (Cyto-C). Cyto-C binds with Apaf1 and Caspase-9 to form an apoptosome. The apoptosome activates Caspase 3, which ultimately results in the death of cancer cells.

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The protective effects of silymarin nanoemulsion on 5-fluorouracil-induced gastrointestinal toxicity in rats

5-Fluorouracil (5FUra) is the third most popular chemotherapeutic component employed to treat solid tumors. In the present study, we aimed to appraise the silymarin (SM) and silymarin nanoemulsion (SMN) effect on 5FUra-induced gastrointestinal toxicity in adult male rats. A total of 30 male Wistar rats were divided into 6 groups including the control (Crl) group, and groups treated with SMN (5 mg.kg⁻¹), SM (5 mg.kg⁻¹), 5FUra + SMN (5 mg.kg⁻¹), and 5FUra + SM (5 mg.kg⁻¹) by IP injection for 14 days. And gastrointestinal toxicity was induced by a single intraperitoneal (IP) injection of 5FUra (100 mg.kg⁻¹) for the last group in the study. Treating rats with SM and SMN diminished elevating malondialdehyde (MDA) levels, and improved total antioxidant capacity (TAC) levels. Also, the intensity of mRNA expression of interleukin-2 (IL-2) and tumor necrosis factor-alpha (TNF-α) caused by 5FUra in the gastrointestinal tissue tract, and macroscopic oral ulcerations decreased, ass well as weight loss was prevented, particularly in the SMN group. Moreover, in the microscopic scope, there were significant improvements in the levels of hyperemia, hyaline, and inflammatory cell infiltration in the tongue, esophagus, and intestinal tissues in the FUra + SMN and FUra + SM groups compared to 5FUra. Hence, treatment with SM and SMN reduced oxidative stress, histopathological degeneration, and gene expression of inflammatory markers in the gastrointestinal tract. According to the results, treatment with SM and SMN markedly decreases the gastrointestinal toxicity caused by 5FUra.     

The epigenetic face of lupus: Focus on antigen-presenting cells

In recent years, epigenetic mechanisms became widely known due to their ability to regulate and maintain physiological processes such as cell growth, development, differentiation and genomic stability. When dysregulated, epigenetic mechanisms, may introduce gene expression changes and disturbance in immune homeostasis leading to autoimmune diseases. Systemic lupus erythematosus (SLE), the most extensively studied autoimmune disorder, has already been correlated with epigenetic modifications, especially in T cells. Since these cell rely on antigen presentation, it may be assumed that erroneous activity of antigen-presenting cells (APCs), culminates in T cell abnormalities. In this review we summarize and discuss the epigenetic modifications in SLE affected APCs, with the focus on dendritic cells (DCs), B cells and monocytes. Unravelling this aspect of SLE pathogenesis, might result in identification of new disease biomarkers and putative therapeutic approaches.     

Screening and identification of potential MERS-CoV papain-like protease (PLpro) inhibitors; Steady-state kinetic and Molecular dynamic studies

MERS-CoV belongs to the coronavirus group. Recent years have seen a rash of coronavirus epidemics. In June 2012, MERS-CoV was discovered in the Kingdom of Saudi Arabia, with 2,591 MERSA cases confirmed by lab tests by the end of August 2022 and 894 deaths at a case-fatality ratio (CFR) of 34.5% documented worldwide. Saudi Arabia reported the majority of these cases, with 2,184 cases and 813 deaths (CFR: 37.2%), necessitating a thorough understanding of the molecular machinery of MERS-CoV. To develop antiviral medicines, illustrative investigation of the protein in coronavirus subunits are required to increase our understanding of the subject. In this study, recombinant expression and purification of MERS-CoV (PLpro), a primary goal for the development of 22 new inhibitors, were completed using a high throughput screening methodology that employed fragment-based libraries in conjunction with structure-based virtual screening. Compounds 2, 7, and 20, showed significant biological activity. Moreover, a docking analysis revealed that the three compounds had favorable binding mood and binding free energy. Molecular dynamic simulation demonstrated the stability of compound 2 (2-((Benzimidazol-2-yl) thio)-1-arylethan-1-ones) the strongest inhibitory activity against the PLpro enzyme. In addition, disubstitutions at the meta and para locations are the only substitutions that may boost the inhibitory action against PLpro. Compound 2 was chosen as a MERS-CoV PLpro inhibitor after passing absorption, distribution, metabolism, and excretion studies; however, further investigations are required.     

Safety and tolerability of Empagliflozin use during the holy month of Ramadan by fasting patients with type 2 diabetes: A prospective cohort study

BackgroundType 2 Diabetes Mellitus (T2DM) patients are exposed to a 7.5 times higher risk of hypoglycemia while fasting during Ramadan. Relevant diabetes guidelines prioritize the use of SGLT2 inhibitors over other classes. There is a great need to enrich data on their safe and effective use by fasting patients at greater risk of hypoglycemia. Therefore, this study aims to assess the safety and tolerability of Empagliflozin in T2DM Muslim patients during Ramadan.MethodologyA prospective cohort study was conducted for adult Muslim T2DM patients. Patients who met the inclusion criteria were categorized into two sub-cohorts based on Empagliflozin use during Ramadan (Control versus Empagliflozin). The primary outcomes were the incidence of hypoglycemia symptoms and confirmed hypoglycemia. Other outcomes were secondary. All patients were followed up to eight weeks post-Ramadan. A propensity score (PS) matching and Risk Ratio (RR) were used to report the outcomes.ResultsAmong 1104 patients with T2DM who were screened, 220 patients were included, and Empagliflozin was given to 89 patients as an add-on to OHDs. After matching with PS (1:1 ratio), the two groups were comparable. The use of other OHDs, such as sulfonylurea, DPP4 inhibitors, and Biguanides, was not statistically different between the two groups. The risk of hypoglycemia symptoms during Ramadan was lower in patients who received Empagliflozin than in the control group (RR 0.48 CI 0.26, 0.89; p-value = 0.02). Additionally, the risk of confirmed hypoglycemia was not statistically significant between the two groups (RR 1.09 CI 0.37, 3.22; p-value = 0.89).ConclusionEmpagliflozin use during Ramadan fasting was associated with a lower risk of hypoglycemia symptoms and higher tolerability. Further randomized control trials are required to confirm these findings.     

IFN regulatory Factor-1 induced macrophage pyroptosis by modulating m6A modification of circ_0029589 in patients with acute coronary syndrome

BackgroundPyroptosis is identified as a novel form of inflammatory programmed cell death and has been recently found to be closely related to atherosclerosis (AS). We found that IFN regulatory factor-1(IRF-1) effectively promotes macrophage pyroptosis in patients with acute coronary syndrome (ACS). Subsequent studies have demonstrated that circRNAs are implicated in AS. However, the underlying mechanisms of circRNAs in macrophage pyroptosis remain elusive.MethodsWe detected the RNA expression of hsa_circ_0002984, hsa_circ_0010283 and hsa_circ_0029589 in human PBMC-derived macrophages from patients with coronary artery disease (CAD). The lentiviral recombinant vector for hsa_circ_0029589 overexpression (pLC5-GFP-circ_0029589) and small interference RNAs targeting hsa_circ_0029589 and METTL3 were constructed. Then, macrophages were transfected with pLC5-GFP-circ_0029589, si-circ_0029589 or si-METTL3 after IRF-1 was overexpressed and to explore the potential mechanism of hsa_circ_0029589 involved in IRF-1 induced macrophage pyroptosis.ResultsThe relative RNA expression level of hsa_circ_0029589 in macrophages was decreased, whereas the N6-methyladenosine (m6A) level of hsa_circ_0029589 and the expression of m6A methyltransferase METTL3 were validated to be significantly elevated in macrophages in patients with ACS. Furthermore, overexpression of IRF-1 suppressed the expression of hsa_circ_0029589, but induced its m6A level along with the expression of METTL3 in macrophages. Additionally, either overexpression of hsa_circ_0029589 or inhibition of METTL3 significantly increased the expression of hsa_circ_0029589 and attenuated macrophage pyroptosis.ConclusionOur observations suggest a novel mechanism by which IRF-1 facilitates macrophage pyroptosis and inflammation in ACS and AS by inhibiting circ_0029589 through promoting its m6A modification.     

Berberine diminishes cancer cell PD-L1 expression and facilitates antitumor immunity via inhibiting the deubiquitination activity of CSN5

Programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1) blocking therapy has become a major pillar of cancer immunotherapy. Compared with antibodies targeting, small-molecule checkpoint inhibitors which have favorable pharmacokinetics are urgently needed. Here we identified berberine (BBR), a proven anti-inflammation drug, as a negative regulator of PD-L1 from a set of traditional Chinese medicine (TCM) chemical monomers. BBR enhanced the sensitivity of tumour cells to co-cultured T-cells by decreasing the level of PD-L1 in cancer cells. In addition, BBR exerted its antitumor effect in Lewis tumor xenograft mice through enhancing tumor-infiltrating T-cell immunity and attenuating the activation of immunosuppressive myeloid-derived suppressor cells (MDSCs) and regulatory T-cells (Tregs). BBR triggered PD-L1 degradation through ubiquitin (Ub)/proteasome-dependent pathway. Remarkably, BBR selectively bound to the glutamic acid 76 of constitutive photomorphogenic-9 signalosome 5 (CSN5) and inhibited PD-1/PD-L1 axis through its deubiquitination activity, resulting in ubiquitination and degradation of PD-L1. Our data reveals a previously unrecognized antitumor mechanism of BBR, suggesting BBR is small-molecule immune checkpoint inhibitor for cancer treatment.     

Bile Duct Obstruction Leads to Increased Intestinal Expression of Breast Cancer Resistance Protein With Reduced Gastrointestinal Absorption of Imatinib

Liver dysfunction reduces systemic clearance of drugs that are primarily eliminated by the liver. However, liver dysfunction can cause a reduction in the plasma concentration profiles of certain drugs, including several tyrosine kinase inhibitors, after oral administration. The aim of the present study was to clarify the reduction in oral absorption of a tyrosine kinase inhibitor, imatinib, and the mechanisms of action involved under conditions of hepatic dysfunction, focusing on intestinal transporters. The maximum plasma concentration of imatinib after oral administration in mice subjected to bile duct ligation (BDL) was lower than that in sham-operated mice, whereas the plasma concentration profile after intravenous administration was essentially unaffected by BDL. The change in maximum plasma concentration was compatible with a reduction in small intestinal permeability of imatinib observed in the in situ closed loop. Gene expression of abcg2 was increased in BDL mice compared with that in sham-operated mice. Expression of breast cancer resistance protein and P-glycoprotein in the small intestinal brush border membrane fraction from BDL mice was also increased compared with that in sham-operated mice. In summary, the intestinal absorption and permeability of imatinib was decreased in BDL mice, and this may be attributed to the up-regulation of the efflux transporter(s).     

Opportunities for overcoming tuberculosis: Emerging targets and their inhibitors

Tuberculosis (TB), an airborne infectious disease mainly caused by Mycobacterium tuberculosis (Mtb), remains a leading cause of human morbidity and mortality worldwide. Given the alarming rise of resistance to anti-TB drugs and latent TB infection (LTBI), new targets and novel bioactive compounds are urgently needed for the treatment of this disease. We provide an overview of the recent advances in anti-TB drug discovery, emphasizing several newly validated targets for which an inhibitor has been reported in the past five years. Our review presents several attractive directions that have potential for the development of next-generation therapies.     

Targeting human MutT homolog 1 (MTH1) for cancer eradication: current progress and perspectives

Since accelerated metabolism produces much higher levels of reactive oxygen species (ROS) in cancer cells compared to ROS levels found in normal cells, human MutT homolog 1 (MTH1), which sanitizes oxidized nucleotide pools, was recently demonstrated to be crucial for the survival of cancer cells, but not required for the proliferation of normal cells. Therefore, dozens of MTH1 inhibitors have been developed with the aim of suppressing cancer growth by accumulating oxidative damage in cancer cells. While several inhibitors were indeed confirmed to be effective, some inhibitors failed to kill cancer cells, complicating MTH1 as a viable target for cancer eradication. In this review, we summarize the current status of developing MTH1 inhibitors as drug candidates, classify the MTH1 inhibitors based on their structures, and offer our perspectives toward the therapeutic potential against cancer through the targeting of MTH1.