Unraveling the neuroprotective mechanisms of naltrexone against aluminum-induced neurotoxicity.

Aluminum (Al) is a known neurotoxic trace element linked to Alzheimer's disease (AD). Naltrexone, an opioid antagonist, has shown promising effects in reducing neuroinflammation at lower doses than those prescribed for addiction. This study aimed to determine the neuroprotective effects of naltrexone on Al-induced neurotoxicity in an in vitro AD model. The SH-SY5Y cells were first cultivated in a standard growth medium. Subsequently, the cells were induced to differentiate by decreasing the concentration of fetal bovine serum and introducing retinoic acid (RA) into the culture media. Subsequently, the inclusion of brain-derived neurotrophic factor (BDNF) was implemented in conjunction with RA. The process of differentiation was concluded on the seventh day. Study groups (n = 3) were designed as the control group, naltrexone group, Al group, Al-Nal group, Alzheimer' model (AD) group, Alzheimer model + Al-exposed group (AD-Al), Alzheimer model + Nal applied group (AD-Nal) and Alzheimer model + Al-exposed + Nal applied group (AD-Al-Nal). Hyperphosphorylated Tau protein as the specific marker of AD was measured in all groups. Glycogen synthase kinase-3 (GSK-3)ß, Protein phosphatase 2A (PP2A), Akt and Wnt signaling pathways were analyzed comparatively. In addition, oxidative stress parameters (total antioxidant capacity, lipid peroxidase, protein carbonyl and reactive oxygen species) were measured comparatively in the study groups. The results showed that naltrexone reduced hyperphosphorylated tau protein levels by regulating GSK-3ß, PP2A, Akt and Wnt signaling. Also, exposure to naltrexone decreased oxidative stress parameters. Based on these results, naltrexone shows promise as a potential therapy for AD, subject to additional clinical assessments.

Evaluation of possible neuroprotective effects of virgin coconut oil on aluminum-induced neurotoxicity in an in vitro Alzheimer's disease model.

Alzheimer's disease (AD) is a progressive neurological disorder that affects various cognitive functions, behavior, and personality. AD is thought to be caused by a combination of genetic and environmental factors, including exposure to aluminum (Al). Virgin coconut oil (VCO) may have potential as a natural neuroprotectant against AD. Aim of this study was to determine neuroprotective effects of VCO on Al-induced neurotoxicity in an in vitro AD model. SH-SY5Y cells were initially cultured in normal growth medium and then differentiated by reducing fetal bovine serum content and adding retinoic acid (RA). Later, brain-derived neurotrophic factor (BDNF) was added along with RA. The differentiation process was completed on the seventh day. Study groups (n = 3) were designed as control group, VCO group, Al group, Al-VCO group, Alzheimer model (AD) group, AD + Al-exposed group (AD+Al), AD + VCO applied group (AD + VCO) and AD + Al-exposed + VCO applied group (AD + Al + VCO). Specific markers of AD (hyperphosphorylated Tau protein, amyloid beta 1-40 peptide, and amyloid precursor protein) were measured in all groups. In addition, oxidative stress parameters (total antioxidant capacity, lipid peroxidase, protein carbonyl, and reactive oxygen species) and neurotransmitter-related parameters (dopamine, dopamine transporter acetylcholine, and synuclein alpha levels, acetylcholinesterase activity) were measured comparatively in the study groups. VCO reduced amyloid beta and hyperphosphorylated Tau protein levels in the study groups. In addition, oxidative stress levels decreased, and neurotransmitter parameters improved with VCO. Our study shows that VCO may have potential therapeutic effects in Alzheimer's disease and further experiments are needed to determine its efficacy.

Antioxidant dihydrolipolic acid protects against in vitro aluminum-induced toxicity.

Dihydrolipoic acid (DHLA) is a natural antioxidant known for its ability to counteract metal toxicity and oxidative stress. It has shown the potential to safeguard cells from harmful environmental substances. It may hold therapeutic benefits in treating neurodegenerative disorders by defending against oxidative damage and chronic inflammation. Thus, this study aimed to explore the potential neuroprotective effects of DHLA against aluminum (Al)-induced toxicity using an Alzheimer's disease (AD) model in vitro. The study focused on two important pathways: GSK-3ß and the Wnt signaling pathways. The SH-SY5Y cell line was differentiated to establish AD, and the study group were as follows: control, Al, DHLA, Al-DHLA, AD, AD-Al, AD-DHLA, and AD-Al-DHLA. The impact of DHLA on parameters related to oxidative stress was assessed. The activity of the GSK-3ß pathway was measured by evaluating the levels of PPP1CA, PP2A, GSK-3ß, and Akt. The Wnt signaling pathway was assessed by measuring Wnt/ß-catenin in the different study groups. Exposure to DHLA significantly reduced oxidative stress by effectively decreasing the levels of reactive oxygen species, thereby protecting against protein oxidation and limiting the production of malonaldehyde. Moreover, the DHLA-treated groups exhibited a remarkable increase in the total antioxidant capacity. Furthermore, the study observed an upregulation of the Wnt signaling pathway and a downregulation of the GSK-3ß pathway in the groups treated with DHLA. In summary, the neuroprotective effects of DHLA, primarily achieved by reducing oxidative stress and modulating critical imbalanced pathways associated with AD, indicate its potential as a promising addition to the treatment regimens of AD patients.

Evaluation of microRNA let-7b-3p expression levels in methamphetamine abuse.

OBJECTIVE: In this study, we aimed to identify a microRNA expression signature that could be used to distinguish methamphetamine from control samples. We also utilized the existing bioinformatics tools in order to predict the candidate microRNAs that could play potential key roles in regulating drug addiction-related genes. METHODS: Methamphetamine samples from 21 ventral tegmental area and 21 nucleus accumbens samples and their control regions were obtained from the Council of Forensic Medicine (Istanbul). Quantitative analysis of let-7b-3p was studied using quantitative reverse transcription PCR. Statistical analysis was carried out using Student's t-test. The receiver operating characteristic curves were plotted with Statistical Package for the Social Sciences (SPSS 20.0). RESULTS: Our quantitative reverse transcription PCR results revealed that let-7b-3p was significantly overexpressed in brain tissues of the methamphetamine-user group. Let-7b-3p had significant power to discriminate methamphetamine from control samples in the ventral tegmental area (AUC; 0.922) and nucleus accumbens (AUC; 0.899) regions. CONCLUSION: We have shown for the first time in the literature the differential expression of let-7b-3p in samples from methamphetamine-addicted individuals. We suggest that let-7b-3p could be a powerful marker for the diagnosis of methamphetamine addiction. Our results showed that differentially expressed let-7b-3p in methamphetamine users could be used as a diagnostic and therapeutic marker.

Evaluation of microRNA let-7b-3p expression levels in methamphetamine abuse

SUMMARY OBJECTIVE: In this study, we aimed to identify a microRNA expression signature that could be used to distinguish methamphetamine from control samples. We also utilized the existing bioinformatics tools in order to predict the candidate microRNAs that could play potential key roles in regulating drug addiction-related genes. METHODS: Methamphetamine samples from 21 ventral tegmental area and 21 nucleus accumbens samples and their control regions were obtained from the Council of Forensic Medicine (Istanbul). Quantitative analysis of let-7b-3p was studied using quantitative reverse transcription PCR. Statistical analysis was carried out using Student's t-test. The receiver operating characteristic curves were plotted with Statistical Package for the Social Sciences (SPSS 20.0). RESULTS: Our quantitative reverse transcription PCR results revealed that let-7b-3p was significantly overexpressed in brain tissues of the methamphetamine-user group. Let-7b-3p had significant power to discriminate methamphetamine from control samples in the ventral tegmental area (AUC; 0.922) and nucleus accumbens (AUC; 0.899) regions. CONCLUSION: We have shown for the first time in the literature the differential expression of let-7b-3p in samples from methamphetamine-addicted individuals. We suggest that let-7b-3p could be a powerful marker for the diagnosis of methamphetamine addiction. Our results showed that differentially expressed let-7b-3p in methamphetamine users could be used as a diagnostic and therapeutic marker.

Impact of a Coronavirus Pandemic on Smoking Behavior in University Students: An Online Survey in Türkiye.

Objectives: Coronavirus Disease-2019 (COVID-19) pandemic has a massive impact on human health, causing sudden lifestyle changes. As it affects health, determining the lifestyles of university students related to smoking has gained importance. This study provides evidence of change in smoking behavior among university students in Türkiye during the ongoing COVID-19 pandemic. Materials and Methods: This cross-sectional survey study was conducted via an electronic questionnaire approximately 2020-2021 among university students in Türkiye. The study comprised a structured questionnaire that inquired about demographic information; and the Fagerström Test for Nicotine Dependence. The questionnaire was distributed randomly to university students; it required 6 min to complete. Results: A total of 749 respondents were included in the study, aged between 19 and 35 years (54.8% females). Of 749 participants, 571 health science students (medicine, pharmacy, dentistry, etc.) completed the survey. The pre-pandemic and COVID-19 pandemic mean nicotine dependence scores were 3.03 and 2.97, respectively. A difference was seen pre-pandemic (p= 0.002) and during pandemic (p= 0.005) for those studying in health and other departments. Students who had middle socio-economical status had significantly higher nicotine dependence scores pre- COVID-19, compared to during the pandemic (p= 0.027). Compared to pre and during the pandemic, the mean score of dependence was significantly lower in students, whose parents were non-smokers during the pandemic. Conclusion: In this study, we have provided the first data on the Turkish university student's nicotine dependence changes during the COVID-19 lockdown. The nicotine dependence level may change based on various factors including behavioral changes. Crucial times such as pandemics can affect individuals, thus, smoking addiction can increase. Behavioral support for quitting smoking such as digital platforms, internet, and television programs should also assist to support smokers quitting successfully during this supreme time.

Quinazolinone-based benzenesulfonamides with low toxicity and high affinity as monoamine oxidase-A inhibitors: Synthesis, biological evaluation and induced-fit docking studies.

The research in selective monoamine oxidases (MAO-A and MAO-B) inhibitors has been increased due to their therapeutic value for neurodegenerative diseases. In this study, 4-((2-(aryl)-4-oxoquinazolin-3(4H)-yl)amino)benzenesulfonamides were synthesized and their MAOs inhibition potentials were investigated applying in vitro fluorometric technique. The most potent compounds 7 and 8 against MAO-A had IC50 values of 0.058 ± 0.002 and 0.094 ± 0.003 µM, respectively, while the reference moclobemide had an IC50 value of 6.061 µM. Compounds 7 (>1724 times) and 8 (>1063 times) more selective and reversible inhibitors of MAO-A rather than MAO-B. Toxicity studies of 7 (IC50 = 210.23 µM) and 8 (IC50 = 259.27 µM) showed that compounds can be considered as non-toxic towards SH-SY5Y cell line at their effective concentrations against MAO-A. In silico docking simulations successfully explained the observed activities and also highlighted structural water molecules to play a key role in the ligand-enzyme interactions. Calculated molecular descriptors are also obeying Lipinski's rule of five and brain/blood partition coefficients, a critical parameter in neurodegenerative diseases. These reversible inhibitors can have considerable advantages compared to irreversible inhibitors which may possess serious pharmacological side effects.

MDMA Abuse in Relation to MicroRNA Variation in Human Brain Ventral Tegmental Area and Nucleus Accumbens.

3,4-methylenedioxymethamphetamine (MDMA) is one of the most widespread illegal drugs, that have been used particularly by young people in the 15-34 age group. MicroRNAs (miRNAs) are endogenously synthesized, non-coding, and small RNAs that post-transcriptionally regulate their target genes' expression by inhibiting protein translation or degradation. miRNAs are increasingly implicated in drug-related gene expressions and functions. Notably, there are no reports of miRNA variation in the human brain in MDMA abuse. We here present a miRNA profiling study - the first such study, to the best of our knowledge - into the post-mortem human brains of a sample of people with MDMA abuse, along with non-drug dependent controls. The miRNA profiling of nucleus accumbens (NAc) and ventral tegmental areas (VTA) was performed by microarray analysis. Subsequently, two candidate miRNA putative biomarkers were selected according to significant regional differential expression (miR-1202 and miR-7975), using quantitative reverse-transcription PCR (qRT-PCR). We showed that the expression level of miR-7975 was significantly lower in the VTA regions of the 30 MDMA users, as compared with the 30 control samples. Another significantly deregulated miR-1202 was down-regulated in the NAc regions of 30 MDMA samples in comparison to the control samples. Alteration of these miRNAs can potentially serve as novel biomarkers for MDMA abuse, and warrant further research in independent and larger samples of patients.

A Meta-Analysis: Identification of Common Mir-145 Target Genes that have Similar Behavior in Different GEO Datasets.

BACKGROUND: MicroRNAs, which are small regulatory RNAs, post-transcriptionally regulate gene expression by binding 3'-UTR of their mRNA targets. Their deregulation has been shown to cause increased proliferation, migration, invasion, and apoptosis. miR-145, an important tumor supressor microRNA, has shown to be downregulated in many cancer types and has crucial roles in tumor initiation, progression, metastasis, invasion, recurrence, and chemo-radioresistance. Our aim is to investigate potential common target genes of miR-145, and to help understanding the underlying molecular pathways of tumor pathogenesis in association with those common target genes. METHODS: Eight published microarray datasets, where targets of mir-145 were investigated in cell lines upon mir-145 over expression, were included into this study for meta-analysis. Inter group variabilities were assessed by box-plot analysis. Microarray datasets were analyzed using GEOquery package in Bioconducter 3.2 with R version 3.2.2 and two-way Hierarchical Clustering was used for gene expression data analysis. RESULTS: Meta-analysis of different GEO datasets showed that UNG, FUCA2, DERA, GMFB, TF, and SNX2 were commonly downregulated genes, whereas MYL9 and TAGLN were found to be commonly upregulated upon mir-145 over expression in prostate, breast, esophageal, bladder cancer, and head and neck squamous cell carcinoma. Biological process, molecular function, and pathway analysis of these potential targets of mir-145 through functional enrichments in PPI network demonstrated that those genes are significantly involved in telomere maintenance, DNA binding and repair mechanisms. CONCLUSION: As a conclusion, our results indicated that mir-145, through targeting its common potential targets, may significantly contribute to tumor pathogenesis in distinct cancer types and might serve as an important target for cancer therapy.

Assessment of global and gene-specific DNA methylation in rat liver and kidney in response to non-genotoxic carcinogen exposure.

Altered expression of tumor suppressor genes and oncogenes, which is regulated in part at the level of DNA methylation, is an important event involved in non-genotoxic carcinogenesis. This may serve as a marker for early detection of non-genotoxic carcinogens. Therefore, we evaluated the effects of non-genotoxic hepatocarcinogens, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), hexachlorobenzene (HCB), methapyrilene (MPY) and male rat kidney carcinogens, d-limonene, p-dichlorobenzene (DCB), chloroform and ochratoxin A (OTA) on global and CpG island promoter methylation in their respective target tissues in rats. No significant dose-related effects on global DNA hypomethylation were observed in tissues of rats compared to vehicle controls using LC-MS/MS in response to short-term non-genotoxic carcinogen exposure. Initial experiments investigating gene-specific methylation using methylation-specific PCR and bisulfite sequencing, revealed partial methylation of p16 in the liver of rats treated with HCB and TCDD. However, no treatment related effects on the methylation status of Cx32, e-cadherin, VHL, c-myc, Igfbp2, and p15 were observed. We therefore applied genome-wide DNA methylation analysis using methylated DNA immunoprecipitation combined with microarrays to identify alterations in gene-specific methylation. Under the conditions of our study, some genes were differentially methylated in response to MPY and TCDD, whereas d-limonene, DCB and chloroform did not induce any methylation changes. 90-day OTA treatment revealed enrichment of several categories of genes important in protein kinase activity and mTOR cell signaling process which are related to OTA nephrocarcinogenicity.

Role of fumonisin B1 on DNA methylation changes in rat kidney and liver cells.

CONTEXT: Fumonisin B1 (FB1) is a mycotoxin produced by Fusarium verticillioides (Sacc.) Nirenberg (Nectriaceae) mold that contaminates maize and other agricultural products. Although the effects of FB1 on sphingolipid metabolism are clear, little is known about early molecular changes associated with FB1 carcinogenicity. OBJECTIVE: Alteration on DNA methylation, as an early event in non-genotoxic carcinogenesis, may play an important role in the mechanism of FB1 toxiciy. MATERIALS AND METHODS: Dose-related effects of FB1 (1-50 µM for 24 h) on global DNA methylation by using high-performance liquid chromatography with UV-diode array detection (HPLC-UV/DAD) and CpG promoter methylation by methylation-specific PCR (MSP) were performed in rat liver (Clone 9) and rat kidney (NRK-52E) epithelial cells. RESULTS: Cell viability reduction is 39% and 34% by the XTT test and LDH release in the growth medium is 32% and 26% at 200 µM of FB1 treatment in Clone 9 and NRK-52E cells, respectively. No significant dose-related effects of FB1 on global DNA methylation which ranged from 4 to 5% were observed in both cells compared with controls. Promoter regions of c-myc gene were methylated (>33%) at 10 and 50 µM of FB1 treatment in Clone 9 cells while it was unmethylated in NRK-52E cells. Promoter regions of p15 gene were unmethylated while VHL gene were found to be methylated (>33%) at 10, 25, and 50 µM and 10 and 50 µM of FB1 treatment in Clone 9 and NRK-52E cells, respectively. DISCUSSION AND CONCLUSION: Alteration in DNA methylation might play an important role in the toxicity of FB1 in risk assessment process.