Redox regulation in hydrogen sulfide action: From neurotoxicity to neuroprotection

Hydrogen sulfide responsive nanoplatforms: Novel gas responsive drug delivery carriers for biomedical applications

Hydrogen sulfide (H2S) is a toxic, essential gas used in various biological and physical processes and has been the subject of many targeted studies on its role as a new gas transmitter. These studies have mainly focused on the production and pharmacological side effects caused by H2S. Therefore, effective strategies to remove H2S has become a key research topic. Furthermore, the development of novel nanoplatforms has provided new tools for the targeted removal of H2S. This paper was performed to review the association between H2S and disease, related H2S inhibitory drugs, as well as H2S responsive nanoplatforms (HRNs). This review first analyzed the role of H2S in multiple tissues and conditions. Second, common drugs used to eliminate H2S, as well as their potential for combination with anticancer agents, were summarized. Not only the existing studies on HRNs, but also the inhibition H2S combined with different therapeutic methods were both sorted out in this review. Furthermore, this review provided in-depth analysis of the potential of HRNs about treatment or detection in detail. Finally, potential challenges of HRNs were proposed. This study demonstrates the excellent potential of HRNs for biomedical applications.

Progress and perspective on hydrogen sulfide donors and their biomedical applications

Following the discovery of nitric oxide (NO) and carbon monoxide (CO), hydrogen sulfide (H₂ S) has been identified as the third gasotransmitter in humans. Increasing evidence have shown that H₂ S is of preventive or therapeutic effects on diverse pathological complications. As a consequence, it is of great significance to develop suitable approaches of H₂ S-based therapeutics for biomedical applications. H₂ S-releasing agents (H₂ S donors) play important roles in exploring and understanding the physiological functions of H₂ S. More importantly, accumulating studies have validated the theranostic potential of H₂ S donors in extensive repertoires of in vitro and in vivo disease models. Thus, it is imperative to summarize and update the literatures in this field. In this review, first, the background of H₂ S on its chemical and biological aspects is concisely introduced. Second, the studies regarding the H₂ S-releasing compounds are categorized and described, and accordingly, their H₂ S-donating mechanisms, biological applications, and therapeutic values are also comprehensively delineated and discussed. Necessary comparisons between related H₂ S donors are presented, and the drawbacks of many typical H₂ S donors are analyzed and revealed. Finally, several critical challenges encountered in the development of multifunctional H₂ S donors are discussed, and the direction of their future development as well as their biomedical applications is proposed. We expect that this review will reach extensive audiences across multiple disciplines and promote the innovation of H₂ S biomedicine.

Hydrogen sulfide (H2S) - therapeutic relevance in rehabilitation and balneotherapy Systematic literature review and meta-analysis based on the PRISMA paradig

Background. An active molecule in sulfurous mineral - therapeutic waters and also in sapropelic mud is H2S, a hormetic gaseous molecule that can actively penetrate the skin. While high levels of H2S are extremely toxic, low levels are tolerated and have potential cytoprotective effects, with anti-inflammatory and antioxidant applications. Objective. This systematic review aims to rigorously select related articles and identify within their content the main possible uses of hydrogen sulfide from balneary sources and to explain its physiological mechanisms and therapeutic properties. Methods. To elaborate our systematic review, we have searched for relevant open access articles in 6 international databases: Cochrane , Elsevier , NCBI/PubMed , NCBI/PMC , PEDro , and ISI Web of Knowledge/Science , published from January 2016 until July 2021. The contextually quested keywords combinations/ syntaxes used are specified on this page. The eligible articles were analyzed in detail regarding pathologies addressed by hydrogen sulfide. All articles with any design (reviews, randomized controlled trials, non-randomized controlled trials, case-control studies, cross-sectional studies), if eligible according to the above-mentioned selection methodology, containing in the title the selected combinations, were included in the analysis. Articles were excluded in the second phase if they did not reach the relevance criterion. Results. Our search identified, first, 291 articles. After eliminating the duplicates and non-ISI articles, remained 121 papers. In the second phase, we applied a PEDro selection filter, resulting in 108 articles that passed the relevance criterion and were included in this systematic review. Conclusions. H2S biology and medical relevance are not fully understood and used adequately for sanogenic or medical purposes. More research is needed to fully understand the mechanisms and importance of this therapeutic gase. The link between balneotherapy and medical rehabilitation regarding the usage of hydrogen sulfide emphasises the unity for this medical speciality.

Educating for practice: A new redesigned pedagogical model of clinical forensic medicine

Nowadays, cultivating experts in clinical forensic medicine (CFM) has become a universal problem worldwide. In most English-speaking countries, CFM is traditionally designed as an introduction and incorporation into medical undergraduate training whereas in China it is an essential sub-specialty of forensic science. The scope, missions, and tasks of this discipline vary widely by virtue of the diversity of countries and legal environment, leading to the difference in pedagogical model, even in professional qualities and abilities. Accordingly, it is imperative to uniform and standardize the training model of undergraduate of forensic major. In this article, we describe a redesigned pedagogical model of CFM implemented by the Faculty of Forensic Medicine, which is characterized by: (a) initiating students into comprehension of CFM and raising their awareness of the professional responsibilities; (b) developing students intellectual curiosity of legal and medical issues and educating in advanced techniques of CFM; (c) cultivating students ability of expression and communication in professional terms and providing with educational resources to enhance their professional qualities; and (d) improving teachers ability of imparting knowledge and promoting the development and optimization of teaching evaluation system. In terms of forensic practical and scientific research, plentiful prominent achievements have been currently acquired resulted from this redesigned pedagogical model, which demonstrates its superiority in undergraduate education.

Analysis of factors related to prognosis and death of fish bile poisoning in China: A retrospective study

Fish bile has long been considered to have therapeutic benefits in folk medicine in some Asian countries. However, poisoning incidents and even death sporadically occurred when people consumed fish bile. Herein, we summarize the main characteristics of fish bile poisoning in China including clinical symptoms, treatment strategies and factors being associated with death and affecting prognosis, hoping to provide a reference for the diagnosis and treatment of fish bile poisoning, as well as forensic identification of death cases induced by fish bile poisoning. We suggest that the health authorities should make an effort to enhance people's awareness of the safety of traditional medicine like fish bile so as to reduce the incidence of adverse events.

Alteration of liver immunity by increasing inflammatory response during co-administration of methamphetamine and atazanavir

Objective: Use of methamphetamine (METH) is prevalent among HIV-infected individuals. Previous research has shown that both METH and HIV protease inhibitors exert influences on mitochondrial respiratory metabolism and hepatic nervous system. This study aims to study the joint effect of METH and HIV protease inhibitors on hepatic immune function.Materials and methods: Based on the differentially expressed genes obtained from RNA-seq of the liver from mouse model, the expression levels of CD48 and Macrophage Receptor with Collagenous Structure (MARCO) were examined using qRT-PCR and flow cytometry, and the expression and secretion of cytokines IL-1β, IL-6, IL-8, IL-10, IFN-γ, IFN-β, and TNF-α were determined using qRT-PCR and ELISA in THP-1-derived macrophages.Results: Our results indicated that compared with the control group, CD48 molecules were significantly down-regulated by METH-atazanavir co-treatment, and the expression level of CD48 decreased as METH concentration increases. MARCO molecules were increased, especially at larger doses of METH and atazanavir treatment. In addition, in the presence of METH-atazanavir, the expression and secretion of a series of pro-inflammatory cytokines TNF-α, IL-1β, IL-6, and IL-8 increased while the expression and secretion of anti-inflammatory cytokine IL-10 decreased.Conclusion: These results demonstrated that METH and atazanavir had a combined impact on the liver immunity, suggesting that the co-treatment could enhance inflammatory response and suppress NK cell activation via CD48.

RIP3/MLKL-mediated neuronal necroptosis induced by methamphetamine at 39°C

Methamphetamine is one of the most prevalent drugs abused in the world. Methamphetamine abusers usually present with hyperpyrexia (39°C), hallucination and other psychiatric symptoms. However, the detailed mechanism underlying its neurotoxic action remains elusive. This study investigated the effects of methamphetamine + 39°C on primary cortical neurons from the cortex of embryonic Sprague-Dawley rats. Primary cortex neurons were exposed to 1 mM methamphetamine + 39°C. Propidium iodide staining and lactate dehydrogenase release detection showed that methamphetamine + 39°C triggered obvious necrosis-like death in cultured primary cortical neurons, which could be partially inhibited by receptor-interacting protein-1 (RIP1) inhibitor Necrostatin-1 partially. Western blot assay results showed that there were increases in the expressions of receptor-interacting protein-3 (RIP3) and mixed lineage kinase domain-like protein (MLKL) in the primary cortical neurons treated with 1 mM methamphetamine + 39°C for 3 hours. After pre-treatment with RIP3 inhibitor GSK’872, propidium iodide staining and lactate dehydrogenase release detection showed that neuronal necrosis rate was significantly decreased; RIP3 and MLKL protein expression significantly decreased. Immunohistochemistry staining results also showed that the expressions of RIP3 and MLKL were up-regulated in brain specimens from humans who had died of methamphetamine abuse. Taken together, the above results suggest that methamphetamine + 39°C can induce RIP3/MLKL regulated necroptosis, thereby resulting in neurotoxicity. The study protocol was approved by the Medical Ethics Committee of the Third Xiangya Hospital of Central South University, China (approval numbers: 2017-S026 and 2017-S033) on March 7, 2017.

Current status and potential role of circular RNAs in neurological disorders

Given the importance of non-coding RNAs in modulating normal brain functions and their implications in the treatment of neurological disorders, non-coding RNA-based diagnostic and therapeutic strategies have shown great clinical potential. Circular RNAs (circRNAs) have emerged as potentially important players in this field. Recent studies have indicated that circRNAs might play vital roles in Alzheimer's disease, Parkinson's disease, ischemic brain injury, and neurotoxicity. However, the mechanisms of action of circRNAs have not been fully characterized. We aimed to review recent advances in circRNA research in the brain to provide new insights on the roles of circRNAs in neurological disorders.