The biphasic role of Hspb1 on ferroptotic cell death in Parkinson's disease.

Rationale: Ferroptosis-driven loss of dopaminergic neurons plays a pivotal role in the pathogenesis of Parkinson's disease (PD). In PD patients, Hspb1 is commonly observed at abnormally high levels in the substantia nigra. The precise consequences of Hspb1 overexpression in PD, however, have yet to be fully elucidated. Methods: We used human iPSC-derived dopaminergic neurons and Coniferaldehyde (CFA)-an Nrf2 agonist known for its ability to cross the blood-brain barrier-to investigate the role of Hspb1 in PD. We examined the correlation between Hspb1 overexpression and Nrf2 activation and explored the transcriptional regulation of Hspb1 by Nrf2. Gene deletion techniques were employed to determine the necessity of Nrf2 and Hspb1 for CFA's neuroprotective effects. Results: Our research demonstrated that Nrf2 can upregulate the transcription of Hspb1 by directly binding to its promoter. Deletion of either Nrf2 or Hspb1 gene abolished the neuroprotective effects of CFA. The Nrf2-Hspb1 pathway, newly identified as a defense mechanism against ferroptosis, was shown to be essential for preventing neurodegeneration progression. Additionally, we discovered that prolonged overexpression of Hspb1 leads to neuronal death and that Hspb1 released from ruptured cells can trigger secondary cell death in neighboring cells, exacerbating neuroinflammatory responses. Conclusions: These findings highlight a biphasic role of Hspb1 in PD, where it initially provides neuroprotection through the Nrf2-Hspb1 pathway but ultimately contributes to neurodegeneration and inflammation when overexpressed. Understanding this dual role is crucial for developing therapeutic strategies targeting Hspb1 and Nrf2 in PD.

Combination therapy enhances efficacy and overcomes toxicity of metal-based anti-diabetic agent.

BACKGROUND AND PURPOSE: Metal-based therapeutic agents are limited by the required concentration of metal-based agents. Hereby, we determined if combination with 17ß-oestradiol (E2) could reduce such levels and the therapy still be effective in type 2 diabetes mellitus (T2DM). EXPERIMENTAL APPROACH: The metal-based agent (vanadyl acetylacetonate [VAC])- 17ß-oestradiol (E2) combination is administered using the membrane-permeable graphene quantum dots (GQD), the vehicle, to form the active GQD-E2-VAC complexes, which was characterized by fluorescence spectra, infrared spectra and X-ray photoelectron spectroscopy. In db/db type 2 diabetic mice, the anti-diabetic effects of GQD-E2-VAC complexes were evaluated using blood glucose levels, oral glucose tolerance test (OGTT), serum insulin levels, homeostasis model assessment (homeostasis model assessment of insulin resistance [HOMA-IR] and homeostasis model assessment of ß-cell function [HOMA-ß]), histochemical assays and western blot. KEY RESULTS: In diabetic mice, GQD-E2-VAC complex had comprehensive anti-diabetic effects, including control of hyperglycaemia, improved insulin sensitivity, correction of hyperinsulinaemia and prevention of ß-cell loss. Co-regulation of thioredoxin interacting protein (TXNIP) activation by the combination of metal complex and 17ß-oestradiol contributed to the enhanced anti-diabetic effects. Furthermore, a potent mitochondrial protective antioxidant, coniferaldehyde, significantly potentiates the protective effects of GQD-E2-VAC complexes. CONCLUSION AND IMPLICATIONS: A metal complex-E2 combinatorial approach achieved simultaneously the protection of ß cells and insulin enhancement at an unprecedented low dose, similar to the daily intake of dietary metals in vitamin supplements. This study demonstrates the positive effects of combination and multi-modal therapies towards type 2 diabetes treatment.

Cerebrospinal fluid efflux through dynamic paracellular pores on venules as a missing piece of the brain drainage system.

The glymphatic system plays a key role in the clearance of waste from the parenchyma, and its dysfunction has been associated with the pathogenesis of Alzheimer's disease (AD). However, questions remain regarding its complete mechanisms. Here, we report that efflux of cerebrospinal fluid (CSF)/interstitial fluid (ISF) solutes occurs through a triphasic process that cannot be explained by the current model, but rather hints at the possibility of other, previously undiscovered routes from paravenous spaces to the blood. Using real-time, in vivo observation of efflux, a novel drainage pathway was discovered, in which CSF molecules enter the bloodstream directly through dynamically assembled, trumpet-shaped pores (basolateral ϕ<8 µm; apical ϕ < 2 µm) on the walls of brain venules. As Zn2+ could facilitate the brain clearance of macromolecular ISF solutes, Zn2+-induced reconstruction of the tight junctions (TJs) in vascular endothelial cells may participate in pore formation. Thus, an updated model for glymphatic clearance of brain metabolites and potential regulation is postulated. In addition, deficient clearance of Aß through these asymmetric venule pores was observed in AD model mice, supporting the notion that impaired brain drainage function contributes to Aß accumulation and pathogenic dilation of the perivascular space in AD.

Disseminated tuberculosis in a child during the COVID-19 pandemic: a case report and literature review.

Background: Disseminated tuberculosis is an uncommon but devastating form of tuberculosis, possibly developing with the immune response of patients. COVID-19 infection may produce an immunosuppressive effect with possible implications for tuberculosis dissemination. Case presentation: A 17-year-old female patient with a history of tuberculous pleurisy presented to the hospital with a high fever and life-threatening dyspnea after contracting a COVID-19 infection. Her condition deteriorated rapidly with grand mal epilepsy and acute gastrointestinal bleeding with a grossly depressed CD4 T-cell count, which was indicative of her profoundly immunosuppressed state. After identifying Mycobacterium tuberculosis in her cerebrospinal fluid and a subcutaneous abscess in her left lower back, she was diagnosed with disseminated tuberculosis involving both lungs, the central nervous system, the terminal ileum, the liver, bilateral adnexal tissue, and subcutaneous soft tissue in accordance with the chest and abdominal CT. Empirical treatment was initiated with dexamethasone (5 mg/day) and an anti-tuberculosis regimen of isoniazid, rifampicin, pyrazinamide, amikacin, and meropenem, which was replaced with faropenem after she left the hospital. The therapeutic effect was considered satisfied in the second month of follow-up. Conclusion: To the best of our knowledge, we report the first case report of disseminated tuberculosis after COVID-19 infection. Tuberculosis may disseminate and progress during the COVID-19 pandemic, requiring more significant studies to provide better diagnosis and treatment options for the co-infection.

Different photoreduction processes of Cr(VI) on cellulose-rich and lignin-rich biochar.

In this study, a series of biochar were prepared via pyrolyzing cellulose-rich pakchoi (PBC) and lignin-rich corncob (CBC) to explore the photoreduction process of Cr(VI). X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy confirmed higher oxygenated functional groups in PBC (48.9%-57.1%), whereas CBC exhibited more aromatization properties due to the stable aromatic network in lignin. For PBC, the valence bands decreased from 1.42 eV to 1.20 eV with the increase of pyrolysis temperature from 300 °C to 500 °C; however, an opposite trend was observed for CBC. The photoreduction of Cr(VI) clearly showed that both PBC and CBC had the best performance at the carbonization temperature of 300 °C (named PBC300 and CBC300). It is noted that PBC300 exhibited the most effective photoreduction of Cr(VI), which was about 1.3 times higher than that of CBC300. The maximum reduction capacities of Cr(VI) were 68.2 mg g-1 on PBC300 and 66.1 mg g-1 on CBC300 at pH∼2.0. Compared with the insoluble char substances, dissolved black carbons made more contributions for Cr(VI) photoreduction, ∼70% in PBC and almost 100% in CBC, which suggested that in the case of PBC, the insoluble char and the corresponding dissolved black carbons play an important role in the photoreduction of Cr(VI). However, only dissolved black carbons contributed to Cr(VI) photoreduction on CBC. As the key reaction pathway, the interfacial electron transport dominated Cr(VI) reduction on PBC and CBC. Moreover, the radical of •O2- had some contribution to the reduction of Cr(VI) only in the PBC system. Interestingly, •OH could promote the photoreduction of Cr(VI) in both PBC and CBC systems, which might be due to the fact that •OH facilitated the formation of small molecule fragments. These findings provide an essential basis for evaluating the environmental impact of photocatalytic behaviors of biochar.

Oxygen-containing groups in cellulose and lignin biochar: their roles in U(VI) adsorption.

The adsorption behaviors of cellulose and lignin biochar depend on the evolution of their oxygen-containing groups to some extent. In this study, cellulose-rich pakchoi and lignin-rich corncob were selected to prepare the pyrolytic biochar at variable temperatures, named PBC and CBC, respectively. Their structure-function relationships were in-depth studied via the combination of the adsorption experiments of U(VI) and comprehensive spectral analyses. The maximal adsorption capacity of PBC 300, obtained at 300 °C, was measured as 46.62 mg g-1 for U(VI), which was ⁓1.3 times higher than 35.60 mg g-1 of CBC 300. U(VI) adsorption on PBC and CBC were predominantly ascribed to the coordination interaction between oxygen-containing groups and U(VI). Interestingly, the main complexation groups were distinct in both biochars due to the different inherent evolutions of cellulose and lignin. Volatile d-glucose chains in cellulose were apt to degrade rapidly, and the formed carboxyls acted as the most important sites in PBC. However, the stable aromatic network in lignin led to a slow degradation, and more hydroxyls thus remained in CBC, which controlled U(VI) adsorption. In this study, we obtained greatly cost-effective adsorbents of U(VI) and provided some essential insights into understanding the structural evolution-function relationship of cellulose and lignin biochar.

Vanadium coordination compounds loaded on graphene quantum dots (GQDs) exhibit improved pharmaceutical properties and enhanced anti-diabetic effects.

Vanadium compounds are promising anti-diabetic agents, and graphene quantum dots (GQDs) are emerging as potential drug delivery systems to improve drug solubility in water and membrane transport. Using highly dispersible and water-soluble GQDs, we herein prepared a novel GQD-VO (p-dmada) complex, in which vanadium coordination compounds [VO(p-dmada)] were packed closely on one side of the GQD sheets possibly via the π-π stacking mechanism. The in vitro tests showed that GQD-VO(p-dmada) exhibited membrane permeability (Papp) as good as that of GQDs with reduced cytotoxicity. In vivo tests on type 2 diabetic mice demonstrated that GQD-VO(p-dmada) exhibited a delayed glucose lowering profile but more profound effects on insulin enhancement and ß-cell protection after three-week treatment compared to VO(p-dmada) alone. In addition, GQD alone was observed for the first time to effectively lower the blood lipid levels of the db/db mice. Overall, GQD-VO(p-dmada) showed improved pharmacokinetic performance and hypoglycemic effects, and using GQD as a nanoplatform for drug delivery may provide vast opportunities for the further design of metal-based pharmaceutical agents.

Coniferaldehyde attenuates Alzheimer's pathology via activation of Nrf2 and its targets.

Background: Alzheimer's disease (AD) currently lacks a cure. Because substantial neuronal damage usually occurs before AD is advanced enough for diagnosis, the best hope for disease-modifying AD therapies likely relies on early intervention or even prevention, and targeting multiple pathways implicated in early AD pathogenesis rather than focusing exclusively on excessive production of ß-amyloid (Aß) species. Methods: Coniferaldehyde (CFA), a food flavoring and agonist of NF-E2-related factor 2 (Nrf2), was selected by multimodal in vitro screening, followed by investigation of several downstream effects potentially involved. Furthermore, in the APP/PS1 AD mouse model, the therapeutic effects of CFA (0.2 mmol kg-1d-1) were tested beginning at 3 months of age. Behavioral phenotypes related to learning and memory capacity, brain pathology and biochemistry, including Aß transport, were assessed at different time intervals. Results: CFA promoted neuron viability and showed potent neuroprotective effects, especially on mitochondrial structure and functions. In addition, CFA greatly enhanced the brain clearance of Aß in both free and extracellular vesicle (EV)-contained Aß forms. In the APP/PS1 mouse model, CFA effectively abolished brain Aß deposits and reduced the level of toxic soluble Aß peptides, thus eliminating AD-like pathological changes in the hippocampus and cerebral cortex and preserving learning and memory capacity of the mice. Conclusion: The experimental evidence overall indicated that Nrf2 activation may contribute to the potent anti-AD effects of CFA. With an excellent safety profile, further clinical investigation of coniferaldehyde might bring hope for AD prevention/therapy.

Anti-diabetic vanadyl complexes reduced Alzheimer's disease pathology independent of amyloid plaque deposition.

Association of Alzheimer's disease (AD) with cerebral glucose hypometabolism, likely due to impairments of insulin signaling, has been reported recently, with encouraging results when additional insulin is provided to AD patients. Here, we tested the potential effects of the anti-diabetic vanadium, vanadyl (IV) acetylacetonate (VAC), on AD in vitro and in vivo models. The experimental results showed that VAC at sub-micromolar concentrations improved the viability of neural cells with or without increased ß-amyloid (Aß) burden; and in APP/PS1 transgenic mice, VAC treatment (0.1 mmol kg-1 d-1) preserved cognitive function and attenuated neuron loss, but did not reduce brain Aß plaques. Further studies revealed that VAC attenuated Aß pathogenesis by (i) activation of the PPARγ-AMPK signal transduction pathway, leading to improved glucose and energy metabolism; (ii) up-regulation of the expression of glucose-regulated protein 75 (Grp75), thus suppressing p53-mediated neuronal apoptosis under Aß-related stresses; and (iii) decreasing toxic soluble Aß peptides. Overall, our work suggested that vanadyl complexes may have great potential for effective therapeutic treatment of AD.

Nano-Delivery Vehicles/Adjuvants for DNA Vaccination Against HIV.

More than 75 million people has been infected HIV and it is responsible for nearly 36 million deaths on a global scale. As one of the deadliest infectious diseases, HIV is becoming the urgent issue of the global epidemic to tackle. In order to settle this problem from the source, some effective prevention strategies should be developed to control the pandemic of HIV. Vaccines, especially DNA vaccines, could be the optimal way to control the spread of HIV due to the unparalleled superiority that DNA vaccines could generate long-term humoral and cellular immune responses which could provide protective immunity for HIV. But the naked DNA could hardly enter into cells and is easily degraded by DNases and lysosomes, so designing effective delivery system is a promising strategy. Since delivery system could be constructed to promote efficient delivery of DNA into mammalian cells, protect them from degradation, and also could be established to be a target system to arrive at certain position of expectation. The current review discusses the potential of various nano-delivery vehicles/adjuvants such as polymer, lipid, liposome, peptide and inorganic material in improving efficiency of diverse modalities available for HIV DNA vaccines.

Site-Specific Drug-Releasing Polypeptide Nanocarriers Based on Dual-pH Response for Enhanced Therapeutic Efficacy against Drug-Resistant Tumors.

To enhance effective drug accumulation in drug-resistant tumors, a site-specific drug-releasing polypeptide system (PEG-Phis/Pasp-DOX/CA4) was exploited in response to tumor extracellular and intracellular pH. This system could firstly release the embedded tumor vascular inhibitor (CA4) to transiently 'normalize' vasculature and facilitate drug internalization to tumors efficiently, and then initiate the secondary pH-response to set the conjugated active anticancer drug (DOX) free in tumor cells. The encapsulated system (PEG-Phis/DOX/CA4), both CA4 and DOX embedding in the nanoparticles, was used as a control. Comparing with PEG-Phis/DOX/CA4, PEG-Phis/Pasp-DOX/CA4 exhibited enhanced cytotoxicity against DOX-sensitive and DOX-resistant cells (MCF-7 and MCF-7/ADR). Moreover, PEG-Phis/Pasp-DOX/CA4 resulted in enhanced therapeutic efficacy in drug-resistant tumors with reduced toxicity. These results suggested that this site-specific drug-releasing system could be exploited as a promising treatment for cancers with repeated administration.

Resveratrol induces apoptosis of human chronic myelogenous leukemia cells in vitro through p38 and JNK-regulated H2AX phosphorylation.

AIM: The phosphorylation of histone H2AX, a novel tumor suppressor protein, is involved in regulation of cancer cell apoptosis. The aim of this study was to examine whether H2AX phosphorylation was required for resveratrol-induced apoptosis of human chronic myelogenous leukemia (CML) cells in vitro. METHODS: K562 cells were tested. Cell apoptosis was analyzed using flow cytometry, and the phosphorylation of H2AX and other signaling proteins was examined with Western blotting. To analyze the signaling pathways, the cells were transfected with lentiviral vectors encoding H2AX-wt or specific siRNAs. RESULTS: Treatment of K562 cells with resveratrol (20-100 µmol/L) induced apoptosis and phosphorylation of H2AX at Ser139 in time- and dose-dependent manners, but reduced phosphorylation of histone H3 at Ser10. Resveratrol treatment activated two MAPK family members p38 and JNK, and blocked the activation of another MAPK family member ERK. Pretreatment with the p38 inhibitor SB202190 or the JNK inhibitor SP600125 dose-dependently reduced resveratrol-induced phosphorylation of H2AX, which were also observed when the cells were transfected with p38- or JNK-specific siRNAs. Overexpression of H2AX in K562 cells markedly increased resveratrol-induced apoptosis, whereas overexpression of H2AX-139m (Ser139 was mutated to block phosphorylation) inhibited resveratrol-induced apoptosis. K562 cells transfected with H2AX-specific siRNAs were resistant to resveratrol-induced apoptosis. CONCLUSION: H2AX phosphorylation at Ser139 in human CML cells, which is regulated by p38 and JNK, is essential for resveratrol-induced apoptosis.

H2AX phosphorylation regulated by p38 is involved in Bim expression and apoptosis in chronic myelogenous leukemia cells induced by imatinib.

Increasing evidence suggests that histone H2AX plays a critical role in regulation of tumor cell apoptosis and acts as a novel human tumor suppressor protein. However, the action of H2AX in chronic myelogenous leukemia (CML) cells is unknown. The detailed mechanism and epigenetic regulation by H2AX remain elusive in cancer cells. Here, we report that H2AX was involved in apoptosis of CML cells. Overexpression of H2AX increased apoptotic sensitivity of CML cells (K562) induced by imatinib. However, overexpression of Ser139-mutated H2AX (blocking phosphorylation) decreased sensitivity of K562 cells to apoptosis. Similarly, knockdown of H2AX made K562 cells resistant to apoptotic induction. These results revealed that the function of H2AX involved in apoptosis is strictly related to its phosphorylation (Ser139). Our data further indicated that imatinib may stimulate mitogen-activated protein kinase (MAPK) family member p38, and H2AX phosphorylation followed a similar time course, suggesting a parallel response. H2AX phosphorylation can be blocked by p38 siRNA or its inhibitor. These data demonstrated that H2AX phosphorylation was regulated by p38 MAPK pathway in K562 cells. However, the p38 MAPK downstream, mitogen- and stress-activated protein kinase-1 and -2, which phosphorylated histone H3, were not required for H2AX phosphorylation during apoptosis. Finally, we provided epigenetic evidence that H2AX phosphorylation regulated apoptosis-related gene Bim expression. Blocking of H2AX phosphorylation inhibited Bim gene expression. Taken together, these data demonstrated that H2AX phosphorylation regulated by p38 is involved in Bim expression and apoptosis in CML cells induced by imatinib.

Thulium ion promotes apoptosis of primary mouse bone marrow stromal cells.

Bone is one of the main target organs for the lanthanides (Ln). Biodistribution studies of Tm-based compounds in vivo showed that bone had significant uptake. But the effect of Tm(3+) on primary mouse bone marrow stromal cells (BMSCs) has not been reported. So we investigated the effect and underlying mechanisms of Tm(3+) on BMSCs. Cell viability, cell apoptosis, reactive oxygen species (ROS) level, lactate dehydrogenase (LDH) activity and mitochondrial membrane potential (MMP) were studied. The results indicated that Tm(3+) increased the viability of BMSCs at concentrations of 1×10(−7), 1×10(−6), 1×10(−5), and 1×10(−4) mol/L in a dose-dependent manner, turned to decrease the viability of BMSCs at the highest concentration of 1×10(−3) mol/L for 24, 48, and 72 h. Tm(3+) at 1×10(−3) mol/L promoted apoptosis of BMSCs, increased the ROS and LDH levels, and decreased MMP in BMSCs. Taken together, we demonstrated that Tm(3+) + at 1×10(−3) mol/L might induce cellular apoptosis through mitochondrial pathway. These resultsmay be helpful for more rational application of Tm-based compounds in the future.

Genome-wide transcriptional analysis of apoptosis-related genes and pathways regulated by H2AX in lung cancer A549 cells.

Histone H2AX is a novel tumor suppressor protein and plays an important role in apoptosis of cancer cells. However, the role of H2AX in lung cancer cells is unclear. The detailed mechanism and epigenetic regulation by H2AX remain elusive in cancer cells. We showed that H2AX was involved in apoptosis of lung cancer A549 cells as in other tumor cells. Knockdown of H2AX strongly suppressed apoptosis of A549 cells. We clarified the molecular mechanisms of apoptosis regulated by H2AX based on genome-wide transcriptional analysis. Microarray data analysis demonstrated that H2AX knockdown in A549 cells affected expression of 3,461 genes, including upregulation of 1,435 and downregulation of 2,026. These differentially expressed genes were subjected to bioinformatic analysis for exploring biological processes regulated by H2AX in lung cancer cells. Gene ontology analysis showed that H2AX affected expression of many genes, through which, many important functions including response to stimuli, gene expression, and apoptosis were involved in apoptotic regulation of lung cancer cells. Pathway analysis identified the mitogen-activated protein kinase signaling pathway and apoptosis as the most important pathways targeted by H2AX. Signal transduction pathway networks analysis and chromatin immunoprecipitation assay showed that two core genes, NFKB1 and JUN, were involved in apoptosis regulated by H2AX in lung cancer cells. Taken together, these data provide compelling clues for further exploration of H2AX function in cancer cells.

Screening patients with diabetes mellitus for tuberculosis in China.

OBJECTIVE: There is a high burden of both diabetes (DM) and tuberculosis (TB) in China, and as DM increases the risk of TB and adversely affects TB treatment outcomes, there is a need for bidirectional screening of the two diseases. How this is best performed is not well determined. In this pilot project in China, we aimed to assess the feasibility and results of screening DM patients for TB within the routine healthcare setting of five DM clinics. METHOD: Agreement on how to screen, monitor and record was reached in May 2011 at a national stakeholders meeting, and training was carried out for staff in the five clinics in July 2011. Implementation started in September 2011, and we report on 7 months of activities up to 31 March 2012. DM patients were screened for TB at each clinic attendance using a symptom-based enquiry, and those positive to any symptom were referred for TB investigations. RESULTS: In the three quarters, 72% of 3174 patients, 79% of 7196 patients and 68% of 4972 patients were recorded as having been screened for TB, resulting in 7 patients found who were already known to have TB, 92 with a positive TB symptom screen and 48 of these newly diagnosed with TB as a result of referral and investigation. All patients except one were started on anti-TB treatment. TB case notification rates in screened DM patients were several times higher than those of the general population, were highest for the five sites combined in the final quarter (774/100 000) and were highest in one of the five clinics in the final quarter (804/100 000) where there was intensive in-house training, special assignment of staff for screening and colocation of services. CONCLUSION: This pilot project shows that it is feasible to carry out screening of DM patients for TB resulting in high detection rates of TB. This has major public health and patient-related implications.