Alpha-synuclein interaction with mitochondria is the final mechanism of ferroptotic death induced by erastin in SH-SY5Y cells

Ferroptosis has been characterized as a form of iron-dependent regulated cell death accompanied by an accumulation of reactive oxygen species and lipid oxidation products along with typical morphological alterations in mitochondria. Ferroptosis is activated by diverse triggers and inhibited by ferrostatin-1 and liproxstatin-1, apart from iron chelators and several antioxidants, and the process is implicated in multiple pathological conditions. There are, however, certain ambiguities about ferroptosis, especially regarding the final executioner of cell death subsequent to the accumulation of ROS. This study uses a typical inducer of ferroptosis such as erastin on SH-SY5Y cells, and shows clearly that ferroptotic death of cells is accompanied by the loss of mitochondrial membrane potential and intracellular ATP content along with an accumulation of oxidative stress markers. All these are prevented by ferrostatin-1 and liproxstatin-1. Additionally, cyclosporine A prevents mitochondrial alterations and cell death induced by erastin implying the crucial role of mitochondrial permeability transition pore (mPTP) activation in ferroptotic death. Furthermore, an accumulation of α-synuclein occurs during erastin induced ferroptosis which can be inhibited by ferrostatin-1 and liproxstatin-1. When the knock-down of α-synuclein expression is performed by specific siRNA treatment of SH-SY5Y cells, the mitochondrial impairment and ferroptotic death of the cells induced by erastin are markedly prevented. Thus, α-synuclein through the involvement of mPTP appears to be the key executioner protein of ferroptosis induced by erastin, but it needs to be verified if it is a generalized mechanism of ferroptosis by using other inducers and cell lines.

Enhancing Anti-cancer Activity: Green Synthesis and Cytotoxicity Evaluation of Turmeric-Gold Nanocapsules on A549 Lung Cancer Cells

Background Lung cancer remains a major global health concern, with a notable increase in new cases in recent years. This study aims to investigate the cytotoxic effects of polymeric turmeric-gold nanocapsules on A549 human lung cancer cells, utilizing green-synthesized gold nanoparticles from Curcuma longa L. and ethyl cellulose-based nanocapsules. Methods Gold nanoparticles were synthesized using the aqueous root extract of Curcuma longa L., and the resulting nanoparticles were characterized using UV-Vis, fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and energy dispersive x-ray (EDX) techniques. Subsequently, polymeric nanocapsules of turmeric with encapsulated gold nanoparticles were prepared. The cytotoxicity of these nanocapsules was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay on both A549 lung cancer cell lines and normal cell lines. Results The turmeric-gold nanocapsules exhibited a half maximal inhibitory concentration (IC50) value of 40 μg/ml, while the gold nanoparticles alone showed an IC50 value of 60 μg/ml when tested on A549 cells. Furthermore, apoptosis was observed in A549 cells treated with turmeric-gold nanocapsules. The combination of gold nanoparticles and turmeric polymer (gold turmeric nanocapsules) demonstrated a more potent anti-cancer effect on the lung cancer cell line, with an IC50 value of 40 μg/ml compared to green-synthesized gold nanoparticles (IC50 of 60 μg/ml). Conclusion The utilization of polymeric nanocapsules of turmeric, with green-synthesized gold nanoparticles, presents a promising solution to overcome the limited water solubility of turmeric. The results suggest that the combination of gold nanoparticles and turmeric enhances the cytotoxic effects on A549 human lung cancer cells. These findings contribute to the potential application of turmeric-gold nanocapsules as a novel therapeutic approach in lung cancer research.

Visceral adiposity index and lipid accumulation product index: The promising role in assessing cardiometabolic risk in non-obese patients of PCOS

BACKGROUND

The combination of metabolic disorders like obesity, insulin resistance, reduced glucose tolerance, diabetes mellitus, and dyslipidemia poses an increased risk of cardiovascular events in patients with PCOS which is closely related to increased visceral fat accumulation. This study explored the noninvasive adiposity markers like Visceral Adiposity Index (VAI) and Lipid Accumulation Product (LAP) levels in non-obese PCOS patients and their associations with clinico-metabolic parameters.

METHODS AND MATERIALS

The case-control study was conducted with a total of 66 PCOS cases and 40 healthy controls (aged 18-35). Their lipid profile, fasting insulin levels and homeostatic model of insulin resistance index, VAI, and LAP scores were estimated. The cases were divided into three groups depending on the presence of cardiovascular risk factors. The predictive power of LAP and VAI with respect to cardiovascular outcomes was assessed by ROC curves.

RESULTS

The VAI and LAP scores have shown a significant positive correlation with markers of metabolic syndrome. When multiple risk factors are considered simultaneously, the cutoff value of VAI is 2.59 with 91% sensitivity and 80% specificity, and that of the LAP score is 40.2 with 91% sensitivity and 83% specificity. The area under curves for VAI was 0.935 and for LAP was 0.945 considering the presence of at least three risk factors.

CONCLUSION

The study concluded that with a definitive cutoff value, VAI and LAP were inexpensive, simple, and effective screening tools for cardiometabolic risk assessment in non-obese women with PCOS and can be an effective way to determine long-term cardiovascular outcomes and prevent them.

Evaluating ChatGPT's Ability to Solve Higher-Order Questions on the Competency-Based Medical Education Curriculum in Medical Biochemistry

Background Healthcare-related artificial intelligence (AI) is developing. The capacity of the system to carry out sophisticated cognitive processes, such as problem-solving, decision-making, reasoning, and perceiving, is referred to as higher cognitive thinking in AI. This kind of thinking requires more than just processing facts; it also entails comprehending and working with abstract ideas, evaluating and applying data relevant to the context, and producing new insights based on prior learning and experience. ChatGPT is an artificial intelligence-based conversational software that can engage with people to answer questions and uses natural language processing models. The platform has created a worldwide buzz and keeps setting an ongoing trend in solving many complex problems in various dimensions. Nevertheless, ChatGPT's capacity to correctly respond to queries requiring higher-level thinking in medical biochemistry has not yet been investigated. So, this research aimed to evaluate ChatGPT's aptitude for responding to higher-order questions on medical biochemistry. Objective In this study, our objective was to determine whether ChatGPT can address higher-order problems related to medical biochemistry.​​​​​​ Methods​​​ This cross-sectional study was done online by conversing with the current version of ChatGPT (14 March 2023, which is presently free for registered users). It was presented with 200 medical biochemistry reasoning questions that require higher-order thinking. These questions were randomly picked from the institution's question bank and classified according to the Competency-Based Medical Education (CBME) curriculum's competency modules. The responses were collected and archived for subsequent research. Two expert biochemistry academicians examined the replies on a zero to five scale. The score's accuracy was determined by a one-sample Wilcoxon signed rank test using hypothetical values. Result The AI software answered 200 questions requiring higher-order thinking with a median score of 4.0 (Q1=3.50, Q3=4.50). Using a single sample Wilcoxon signed rank test, the result was less than the hypothetical maximum of five (p=0.001) and comparable to four (p=0.16). There was no difference in the replies to questions from different CBME modules in medical biochemistry (Kruskal-Wallis p=0.39). The inter-rater reliability of the scores scored by two biochemistry faculty members was outstanding (ICC=0.926 (95% CI: 0.814-0.971); F=19; p=0.001)​​​​​​ Conclusion The results of this research indicate that ChatGPT has the potential to be a successful tool for answering questions requiring higher-order thinking in medical biochemistry, with a median score of four out of five. However, continuous training and development with data of recent advances are essential to improve performance and make it functional for the ever-growing field of academic medical usage.

Role of written examination in the assessment of attitude ethics and communication in medical students: Perceptions of medical faculties

BACKGROUND

The study aims to record the perceptions of medical faculties regarding the effectiveness of theory-based examination to assess the newly introduced competencies of attitude ethics and communication (AETCOM) in the competency-based medical curriculum for Indian medical graduates.

MATERIALS AND METHODS

This is an analytical cross-sectional study performed on the month of February 2020 where a prevalidated questionnaire consisting of components of AETCOM was e-mailed to the teaching faculties of IQ City Medical College via Google Forms. Consenting faculties responded. Their results were analyzed by inbuilt Google statistics and were cross-verified with SPSS 20.0.

RESULTS

Sixty percent faculties strongly agree regarding the beneficial role of mandatory inclusion of AETCOM competencies in competency-based medical education. About 61.66% of faculties strongly agree that both formative assessment and summative assessment of AETCOM are essential. Although 48.33% of faculties believed that theoretical questions can be used to assess AETCOM, 51.66% of faculties do not agree that theory examination serves as an effective tool to assess AETCOM. They believe that AETCOM cannot be written on paper and attitude can change in reality when facing a real-world clinical scenario in contrast to what is written in answer script during creative writing.

CONCLUSIONS

Assessment of AETCOM is essential and it should be preferably done via a practical approach in a real-world simulated scenario and not by written theoretical examination.

Ceramide and Sphingosine-1-Phosphate in Cell Death Pathways : Relevance to the Pathogenesis of Alzheimer's Disease

The metabolic turnover of sphingolipids produces several signaling molecules that profoundly affect the proliferation, differentiation and death of cells. In particular, an enormous body of information is available that defines the varied role of ceramide and sphingosine-1-phosphate in cell death and survival. This review specifically examines the role of ceramide and sphingosine-1- phosphate in triggering neuronal death in Alzheimer's disease by analyzing the data from post-mortem studies and experimental research. There is compelling evidence that ceramide plays a key role in the neurodegeneration and amyloidogenesis occurring in the brain in Alzheimer's disease. Further, it appears that ceramide and amyloid beta protein orchestrate an attack on mitochondria to set in the pathways of cell death. However, the complexity of metabolic and signaling pathways of sphingolipid derivatives precludes an immediate identification of effective drug targets for the therapy of Alzheimer's disease.

The Oral Iron Chelator, Deferasirox, Reverses the Age-Dependent Alterations in Iron and Amyloid-β Homeostasis in Rat Brain: Implications in the Therapy of Alzheimer's Disease

The altered metabolism of iron impacts the brain function in multiple deleterious ways during normal aging as well as in Alzheimer's disease. We have shown in this study that chelatable iron accumulates in the aged rat brain along with overexpression of transferrin receptor 1 (TfR1) and ferritin, accompanied by significant alterations in amyloid-β (Aβ) peptide homeostasis in the aging brain, such as an increased production of the amyloid-β protein precursor, a decreased level of neprilysin, and increased accumulation of Aβ42. When aged rats are given daily the iron chelator, deferasirox, over a period of more than 4 months starting from the 18th month, the age-related accumulation of iron and overexpression of TfR1 and ferritin in the brain are significantly prevented. More interestingly, the chelator treatment also considerably reverses the altered Aβ peptide metabolism in the aging brain implying a significant role of iron in the latter phenomenon. Further, other results indicate that iron accumulation results in oxidative stress and the activation of NF-κB in the aged rat brain, which are also reversed by the deferasirox treatment. The analysis of the results together suggests that iron accumulation and oxidative stress interact at multiple levels that include transcriptional and post-transcriptional mechanisms to bring about changes in the expression levels of TfR1 and ferritin and also alterations in Aβ peptide metabolism in the aging rat brain. The efficacy of deferasirox in preventing age-related changes in iron and Aβ peptide metabolism in the aging brain, as shown here, has obvious therapeutic implications for Alzheimer's disease.

α-Synuclein-induced mitochondrial dysfunction in isolated preparation and intact cells: implications in the pathogenesis of Parkinson's disease

This study has shown that purified recombinant human α-synuclein (20 μM) causes membrane depolarization and loss of phosphorylation capacity of isolated purified rat brain mitochondria by activating permeability transition pore complex. In intact SHSY5Y (human neuroblastoma cell line) cells, lactacystin (5 μM), a proteasomal inhibitor, causes an accumulation of α-synuclein with concomitant mitochondrial dysfunction and cell death. The effects of lactacystin on intact SHSY5Y cells are, however, prevented by knocking down α-synuclein expression by specific siRNA. Furthermore, in wild-type (non-transfected) SHSY5Y cells, the effects of lactacystin on mitochondrial function and cell viability are also prevented by cyclosporin A (1 μM) which blocks the activity of the mitochondrial permeability transition pore. Likewise, in wild-type SHSY5Y cells, typical mitochondrial poison like antimycin A (50 nM) produces loss of cell viability comparable to that of lactacystin (5 μM). These data, in combination with those from isolated brain mitochondria, strongly suggest that intracellularly accumulated α-synuclein can interact with mitochondria in intact SHSY5Y cells causing dysfunction of the organelle which drives the cell death under our experimental conditions. The results have clear implications in the pathogenesis of sporadic Parkinson's disease. α-Synuclein is shown to cause mitochondrial impairment through interaction with permeability transition pore complex in isolated preparations. Intracellular accumulation of α-synuclein in SHSY5Y cells following proteasomal inhibition leads to mitochondrial impairment and cell death which could be prevented by knocking down α-synuclein gene. The results link mitochondrial dysfunction and α-synuclein accumulation, two key pathogenic mechanisms of Parkinson's disease, in a common damage pathway.

Raised serum proinflammatory cytokines in Alzheimer's disease with depression

The purpose of the present study was to identify the changes in the levels of proinflammatory cytokines like IL-1β, IL-6 and TNF-α in peripheral circulation in Alzheimer's disease (AD) subjects and to correlate these with associated depression and cognitive deficit. Fifty five AD subjects and thirty seven age and sex matched controls were included in the study. The AD patients were grouped as AD with depression (n= 31) and AD without depression (n= 24). The serum levels of IL-1β, IL-6 and TNF-α were determined by immunoassay by commercially available kits. The serum levels of IL-6 and TNF-α were elevated in AD patients with depression compared to control (p<0.001) or AD without depression (p<0.001). The serum level of IL-1β was higher in AD patients with or without depression as compared to controls. Furthermore, a strong inverse correlation was observed between the MMSE scores and serum levels of IL-6 or TNF-α in AD subjects with depression. The study highlights the important role of peripheral IL-6 and TNF-α in AD associated depression and cognitive deficits.