Neuroprotective effects of mitochondrial-targeted hydrogen sulphide donor, AP39 on H2O2-induced oxidative stress in human neuroblastoma SHSY5Y cell line

Oxidative stress (OS) resulting from imbalance in the generation of reactive oxygen species (ROS) and/or the dysfunction of the antioxidant machinery, is a key mechanism associated with the onset of neurodegenerative disorders. Although the molecular mechanisms are still elusive, the onset of disorders such as Alzheimer's and Parkinson's disease have been associated with mitochondrial dysfunction. Recently, a mitochondrial-targeted hydrogen sulphide (H2S) donor, AP39, has shown to promote cellular bioenergetics in OS related scenarios. The aim of this study was to explore the potential of AP39 to protect the mitochondrial function in an OS environment induced by hydrogen peroxide (H2O2). We assessed the potential effects of increasing concentrations of AP39 on cell viability, H2S availability and the mitochondrial bioenergetic response in resting (non-differentiated and differentiated) neuroblastoma SHSY5Y cell line. Further, we explored the role of AP39 in attenuating H2O2-induced mitochondrial dysfunction. Our results showed that nanomolar to micromolar concentrations of AP39 (0.1 μM – 3 μM) are not toxic to SHSY5Y cells, regardless of their differentiation status. Fluorescence detection of H2S observed AP39 co-localises within the mitochondria in a concentration dependent manner. Whilst a lower concentration of AP39 (0.3 μM) was required to improve the mitochondrial bioenergetics in resting non-differentiated cells, 1 μM produced this effect in their differentiated counterparts. In both, non-differentiated and differentiated cells, AP39 reduced H2O2-induced mitochondrial impairments by improving the parameters of the mitochondrial function and abrogating the generation of mitochondrial ROS. These suggest that mitochondrial targeted delivery of H2S may attenuate neuronal toxicity in neuronal disorders associated with OS-induced mitochondrial dysfunction

Patterns of Drug Utilization and Self-Medication Practices: A Cross Sectional Study

Background: Self-medication (SM) is a growing phenomenon worldwide that has recently been classified as one of the most serious public health problems. SM can result in an incorrect self-diagnosis, inappropriate treatment, potential adverse reactions, interactions, and the masking of more sinister disease. Objectives: To assess the prevalence of SM practices amongst healthcare professionals and the general population in Saudi Arabia and to identify the sociodemographic contributing factors to this practice. Methods: A total of 540 participants were enrolled in this study. Participants were asked to complete the study questionnaire comprising two sections to gather demographic information and to collect data regarding SM practice. Results: The prevalence of SM practice among the study participants was 78.6%, and it was the highest among the middle age groups of (21–40 years) 82% compared to the younger and older age groups. The observed prevalence was higher in the female participants (53.7%) and those who live alone. Type of education did not affect the attitude of SM (p = 0.374); however, level of education strongly affected the prevalence of the SM, with higher incidence among university graduates (p < 0.001). Analgesics with antipyretics properties were the most self-medicated drugs. Patients considering their illnesses minor was the main reason behind the high prevalence of this practice. Among healthcare professions the highest prevalence of SM was found among pharmacists (95%), followed by physicians, nurses, and other medical practitioners. Conclusion: The general population should be better educated and made conscious about the consequences, risks, and side effects of SM. Awareness campaigns may prove to be useful in this matter, allowing the patient to consider the appropriateness of this practice. Individuals in the age group of 21–40 years, females, and those who live alone should be considered priority target populations in the design and implementation of SM awareness projects

Sodium Thiosulphate-Loaded Liposomes Control Hydrogen Sulphide Release and Retain Its Biological Properties in Hypoxia-like Environment

Hypoxia, or insufficient oxygen availability is a common feature in the development of a myriad of cardiovascular-related conditions including ischemic disease. Hydrogen sulphide (H2S) donors, such as sodium thiosulphate (STS), are known for their cardioprotective properties. However, H2S due to its gaseous nature, is released and cleared rapidly, limiting its potential translation to clinical settings. For the first time, we developed and characterised liposome formulations encapsulating STS and explored their potential for modulating STS uptake, H2S release and the ability to retain pro-angiogenic and biological signals in a hypoxia-like environment mirroring oxygen insufficiency in vitro. Liposomes were prepared by varying lipid ratios and characterised for size, polydispersity and charge. STS liposomal encapsulation was confirmed by HPLC-UV detection and STS uptake and H2S release was assessed in vitro. To mimic hypoxia, cobalt chloride (CoCl2) was administered in conjunction with formulated and non-formulated STS, to explore pro-angiogenic and metabolic signals. Optimised liposomal formulation observed a liposome diameter of 146.42 ± 7.34 nm, a polydispersity of 0.22 ± 0.19, and charge of 3.02 ± 1.44 mV, resulting in 25% STS encapsulation. Maximum STS uptake (76.96 ± 3.08%) from liposome encapsulated STS was determined at 24 h. Co-exposure with CoCl2 and liposome encapsulated STS resulted in increased vascular endothelial growth factor mRNA as well as protein expression, enhanced wound closure and increased capillary-like formation. Finally, liposomal STS reversed metabolic switch induced by hypoxia by enhancing mitochondrial bioenergetics. These novel findings provide evidence of a feasible controlled-delivery system for STS, thus H2S, using liposome-based nanoparticles. Likewise, data suggests that in scenarios of hypoxia, liposomal STS is a good therapeutic candidate to sustain pro-angiogenic signals and retain metabolic functions that might be impaired by limited oxygen and nutrient availability

Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10&nbsp;years; 78.2% included were male with a median age of 37&nbsp;years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

Lactate Dehydrogenase/Albumin To-Urea Ratio: A Novel Prognostic Maker for Fatal Clinical Complications in Patients with COVID-19 Infection

Objective: To investigate lactate dehydrogenase/Albumin to-urea (LAU) ratio as a potential predictor for COVID-19-induced fatal clinical complications in hospitalized patients. Methods: This is a retrospective study involving blood analyses from 1139 hospitalised COVID-19 infection survivors and 349 deceased cases post-COVID-19 infection. Laboratory tests included complete blood picture, inflammatory markers, and routine organ function tests. Results: The non-survivor group showed lower haemoglobin (p p p p p p p p ≤ 0.05). LAU ratio had an area under receiver operating characteristic of 0.67 compared to 0.60 with NLR. Conclusion: Patients with a high LAU ratio are at increased risk of mortality due to COVID-19 infection. Therefore, early assessment of this parameter, intensive intervention and close monitoring could improve their prognosis

Transdermal Delivery of a Hydrogen Sulphide Donor, ADT-OH Using Aqueous Gel Formulations for the Treatment of Impaired Vascular Function:an Ex Vivo Study

PURPOSE: Hydrogen sulphide (H2S) is an important signalling molecule involved in the regulation of several physiological and pathophysiological processes. The objective of this study was to investigate the feasibility of transdermal delivery of ADT-OH, a H2S donor, by investigating the transdermal flux of aqueous gels loaded with penetration enhancers or liposomes. Furthermore, we explored the ability of permeated ADT-OH to promote angiogenesis and mitochondrial bioenergetics in HUVEC cells.METHODS: Aqueous hypromellose gels (5% w/v) were prepared with up to 10% v/v propylene glycol (PG) or deformable liposomes with 0.025% w/w ADT-OH. ADT-OH permeation from formulations across excised murine skin into PBS was quantified over 24 h using HPLC-UV detection. Media was collected and applied to HUVEC cells to evidence ADT-OH functionality following permeation. Tube formation assays were performed as indicative of angiogenesis and mitochondrial oxygen consumption was evaluated using a Seahorse XF24.RESULTS: Increasing the loading of PG caused an increase in ADT-OH permeation rate across skin and a decrease in dermal drug retention whereas liposomal gels produced a slow-release profile. Treatment of HUVEC's using conditioned media collected from the ADT-OH loaded permeation studies enhanced tube formation and the basal oxygen consumption rates after 30 min of treatment.CONCLUSIONS: These findings demonstrate that transdermal delivery of ADT-OH may provide a promising approach in the treatment of impaired vascular function. Gels prepared with 10% v/v PG have the potential for use in conditions requiring rapid H2S release whereas liposomal loaded gels for treatment requiring sustained H2S release.</p

Transdermal delivery of mitochondrial-targeted hydrogen sulphide donor, AP39 protects against 6-hydroxydopamine-induced mitochondrial dysfunction

Hydrogen sulphide (H 2S) is an important gaseous signalling molecule with emerging roles as a neuroprotectant. The objective of this study was to investigate the feasibility of transdermal delivery of mitochondrial-targeted H 2S donor, AP39 whilst investigating the ability of permeated AP39 on abrogating 6-hydroxydopamine (6-OH-dop)-induced mitochondrial dysfunction, as a model of Parkinson's disease, established in human neuroblastoma cells, SHSY-5Y. Aqueous hypromellose gels (5% w/v) were prepared with up to 10% v/v propylene glycol (PG) with 0.002% w/w AP39. AP39 permeation from formulations across excised murine skin into PBS was quantified over 24 h using HPLC-UV detection. Media was collected and applied to a microvasculature blood–brain-barrier (BBB) model to evidence AP39 permeability. Following, the permeate was applied to neuroblastoma cells SHSY-5Y to evidence its therapeutic potential in modulating the mitochondrial bioenergetics and antioxidant in response to 6-OH-dop-induced mitochondrial dysfunction. The presence of PG in gel formulations significantly increased the cumulative amount of AP39 permeated across murine skin over 24 h from 24.40 ± 2.39 % to 48.59 ± 2.93 %. Conditioned media applied to a microvasculature BBB model observed AP39 permeation across the barrier and H 2S release. Finally, permeated AP39 enhanced parameters of mitochondrial bioenergetics in SHSY-5Y exposed to 6-OH-dop. Moreover, permeated AP39 abrogated mitochondrial-specific reactive oxygen species generation induced by 6-OH-dop. These findings demonstrate transdermal delivery of AP39 may provide a promising alternative to deliver this mitochondrial-targeted H 2S donor and this approach allows the potential to cross the BBB reaching CNS organs in the treatment of neurodegenerative conditions such as Parkinson's disease. Moreover, our observations show that gels prepared with 10% v/v PG have the potential for use in conditions requiring rapid H 2S delivery whereas gels without PG have potential for therapy requiring sustained H 2S delivery