Methamphetamine mediates apoptosis of vascular smooth muscle cells via the chop-related endoplasmic reticulum stress pathway

Phenylbutyric acid inhibits hypoxia-induced trophoblast apoptosis and autophagy in preeclampsia via the PERK/ATF-4/CHOP pathway

Preeclampsia (PE) is a common pregnancy complication with a high mortality rate. Abnormally activated endoplasmic reticulum stress (ERS) is believed to be responsible for the destruction of key placental cells-trophoblasts. Phenylbutyric acid (4-PBA), an ERS inhibitor, is involved in regulating the development of ERS-related diseases. At present, how 4-PBA affects trophoblasts and its mechanisms is still unclear. In this study, PE cell models were established by stimulating HTR-8/SVneo cells with hypoxia. To verify the underlying mechanisms of 4-PBA on PE, CCT020312, an activator of PERK, was also used. The results showed that 4-PBA restored hypoxia-induced trophoblast viability, inhibited HIF-1α protein expression, inflammation, and PERK/ATF-4/CHOP pathway. Hoechst 33342 staining and flow cytometry results confirmed that 4-PBA decreased hypoxia-induced apoptosis in trophoblasts. The results of the JC-1 analysis and apoptosis initiation enzyme activity assay also demonstrated that 4-PBA inhibited apoptosis related to the mitochondrial pathway. Furthermore, by detecting autophagy in trophoblasts, an increased number of autophagic vesicles, damaged mitochondria, enhanced dansylcadaverine fluorescence, enhanced levels of autophagy proteins Beclin-1, LC3II, and decreased p62 were seen in hypoxia-stimulated cells. These changes were reversed by 4-PBA. Furthermore, it was observed that CCT020312 reversed the effects of 4-PBA on the viability, apoptosis, and autophagosome number of hypoxia-induced trophoblasts. In summary, 4-PBA reduces autophagy and apoptosis via the PERK/ATF-4/CHOP pathway and mitochondrial pathway, thereby restoring the viability of hypoxic trophoblasts. These findings provide a solid evidence base for the use of 4-PBA in PE treatment and guide a new direction for improving the outcomes of patients with PE.

Patulin induces ROS-dependent cardiac cell toxicity by inducing DNA damage and activating endoplasmic reticulum stress apoptotic pathway

Patulin (PAT) is one of the mycotoxins commonly found in agricultural products and fruits, and has obvious toxic effects on animals and humans. PAT has been found to cause myocardial toxicity and oxidative damage, but the mechanism of myocardial toxicity remained to be elucidated. We investigated the toxic effects and potential mechanisms of PAT on human cardiomyocytes and explored the effects of reactive oxygen species (ROS) on them. The study showed that treatment with PAT for 24 h decreased cell viability and superoxide dismutase (SOD) activity, and increased ROS and lactate dehydrogenase (LDH) levels. Moreover, in addition to detecting increased γ-H2AX expression and observing nuclear damage, the comet assay also showed increased DNA tail distance in the PAT-treated group, followed by an increase in phosphorylation of the p53 protein and p21 protein expression, and a decrease in CDK1 and Cyclin B1 protein expression, and G2/M phase arrest. In addition, PAT induced endoplasmic reticulum stress (ERS) and induced apoptosis, as evidenced by Ca2+ increase, ER enlargement and swelling, and upregulation of ERS-related genes and proteins expression, and increased expression of three apoptotic pathway proteins under ERS, including CHOP, JNK, and caspase-12. Meanwhile, N-acetylcysteine (NAC, a ROS scavenger) reversed the negative effects of PAT treatment on cells. These results clarify that excessive ROS production by PAT-treated AC16 cells not only causes DNA damage, leading to cell cycle arrest, but also causes ERS, which triggers apoptotic pathways to cause apoptosis.

Methamphetamine and Designer Stimulants Modulate Tonic Human Cerebrovascular Smooth Muscle Contractility: Relevance to Drug-Induced Neurovascular Stress

To avoid criminal prosecution, clandestine chemists produce designer stimulants that mimic the pharmacological and psychoactive effects of conventional stimulants, such as methamphetamine. Following persistent or high-dose exposure, both acute vasoconstriction and loss of vascular homeostasis are reported dangers of conventional stimulants, and designer stimulants may pose even greater dangers. To compare the effects of a conventional stimulant and two designer stimulants on vascular contraction, this study examined the direct effects of 1,3-benzodioxolylbutanamine (BDB) and N-butylpentylone in comparison to methamphetamine on the function of human brain vascular smooth muscle cells (HBVSMCs). HBVSMCs suspended in collagen gels were exposed to varying concentrations of each drug, and the degree of constriction was assessed over one week. The MTT assay was used to measure the impact of the three drugs on the cellular metabolic activity as a marker of cellular toxicity. The highest concentration tested of either methamphetamine or N-butylpentylone produced a loss of HBVSMC contractility and impaired cellular metabolism. BDB showed a similar pattern of effects, but, uniquely, it also induced vasoconstrictive effects at substantially lower concentrations. Each drug produced direct effects on HBVSMC contraction that may be a mechanism by which the cardiovascular system is damaged following high-dose or persistent exposure, and this could be exacerbated by any sympathomimetic effects of these compounds in whole organisms. BDB appears to impact HBVSMC function in ways distinct from methamphetamine and N-butylpentylone, which may present unique dangers.

Effects of molecular hydrogen intervention on the gut microbiome in methamphetamine abusers with mental disorder

Methamphetamine (METH) is a potent and highly addictive psychostimulant and one of the most widely used illicit drugs, the abuse of which has become a severe public health problem worldwide. A growing amount of evidence has indicated potential connections between gut microbiota and mental disorders induced by METH and associations with neural and metabolic pathways. The present study aimed to explore the relationship between fecal microbial alterations and neuropsychiatric diseases in METH addictions. Thus, mental disorders and gut microbial alterations were analyzed by self-rating depression (SDS) and anxiety (SAS) scales and 16 S rRNA gene sequencing, respectively. Our results showed that increased SDS and SAS indices and decreased alpha diversity indicated more serious mental disorders and lower bacterial diversity in METH users than in the age-matched healthy control group. The gut microbial composition in female METH users was also significantly altered, with reductions in hydrogen-producing bacteria, including Bacteroides and Roseburia. Molecular hydrogen (H₂) is spontaneously produced by intestinal bacteria in the process of anaerobic metabolism, which is the main pathway for H₂ production in vivo. Numerous studies have shown that hydrogen intervention can significantly improve neuropsychiatric diseases, including Alzheimer's disease and Parkinson's disease. Our results showed that hydrogen intervention, including drinking and inhaling, significantly alleviated mental disorders induced by METH abuse, and the inhalation of hydrogen also altered gut microbiota profiles in the METH abusers. These results suggest that hydrogen intervention has potential therapeutic applicability in the treatment of mental disorders in METH abusers.

Roles of selected non-P450 human oxidoreductase enzymes in protective and toxic effects of chemicals: review and compilation of reactions

This is an overview of the metabolic reactions of drugs, natural products, physiological compounds, and other (general) chemicals catalyzed by flavin monooxygenase (FMO), monoamine oxidase (MAO), NAD(P)H quinone oxidoreductase (NQO), and molybdenum hydroxylase enzymes (aldehyde oxidase (AOX) and xanthine oxidoreductase (XOR)), including roles as substrates, inducers, and inhibitors of the enzymes. The metabolism and bioactivation of selected examples of each group (i.e., drugs, "general chemicals," natural products, and physiological compounds) are discussed. We identified a higher fraction of bioactivation reactions for FMO enzymes compared to other enzymes, predominately involving drugs and general chemicals. With MAO enzymes, physiological compounds predominate as substrates, and some products lead to unwanted side effects or illness. AOX and XOR enzymes are molybdenum hydroxylases that catalyze the oxidation of various heteroaromatic rings and aldehydes and the reduction of a number of different functional groups. While neither of these two enzymes contributes substantially to the metabolism of currently marketed drugs, AOX has become a frequently encountered route of metabolism among drug discovery programs in the past 10-15 years. XOR has even less of a role in the metabolism of clinical drugs and preclinical drug candidates than AOX, likely due to narrower substrate specificity.

Geometric and Morphologic Features of Ruptured Intracranial Aneurysms Associated with Methamphetamine Use

BACKGROUND

Methamphetamine (MA) use is associated with poor outcomes after aneurysmal subarachnoid hemorrhage (aSAH). MA exerts both hemodynamic and inflammatory effects, but whether these manifest with altered intracranial aneurysm (IA) remodeling is unknown. The objective of this study was to compare IA geometric and morphologic features in patients with and without MA detected on urine toxicology (Utox) at presentation.

METHODS

160 consecutive patients with SAH and Utox at time of admission were retrospectively reviewed. Geometric-morphologic IA characteristics were assessed by blinded neuroradiologists. Studied features were maximum sac diameter, location, size, ellipsoid volume, aspect ratio, size ratio, volume: neck ratio, dome: neck ratio, bottleneck factor, morphology (saccular, fusiform/dissecting, blister, mycotic), and presence of bleb, vasculopathy, or additional unruptured IA.

RESULTS

Of 139/160 patients with aSAH, 23/139 (16.5%) were Utox MA+ There was no difference in aneurysm subtype frequency, presence of bleb, vasculopathy, or presence an additional (unruptured) aneurysm with trend toward posterior circulation location and higher Hunt and Hess grade (p = 0.09 for both) in MA+ group. Maximum IA sac diameter, ellipsoid volume, dome-neck ratio, and size ratio were similar between groups. Only the aspect ratio (AR) differed between groups (MA+ = 2.20 vs. MA- = 1.74, p = 0.02). The AR remained a significant predictor of Utox MA+ in a multiple logistic regression analysis (odds ratio 1.87, 95% confidence interval 1.06-3.39).

CONCLUSIONS

Active use of methamphetamine is independently associated with larger AR in patients with ruptured IA. This may indicate hazardous remodeling due to hemodynamic and/or inflammatory changes.

Hsa_circ_0056686, derived from cancer-associated fibroblasts, promotes cell proliferation and suppresses apoptosis in uterine leiomyoma through inhibiting endoplasmic reticulum stress

Abnormal expression of circular RNAs (circRNAs) in cancer-associated fibroblasts (CAFs) is involved in the tumor-promoting ability of CAFs. Hsa_ circ_ 0056686 has been reported to affect leiomyoma size. The purpose of this study is to investigate the regulatory role of hsa_circ_0056686 in CAFs on uterine leiomyoma (ULM). The primary CAFs and corresponding normal fibroblasts (NFs) were isolated from the tumor zones of ULM tissues and adjacent, respectively. Hsa_circ_0056686 level was higher in CAFs than NFs, and also higher in ULM tissues than in adjacent tissues. CAFs-CM significantly increased the proliferation and migration and inhibited apoptosis of ULM cells, as confirmed by CCK-8, transwell, and flow cytometry assays. Moreover, conditioned medium (CM) from CAFs transfected with hsa_circ_0056686 shRNA (CAFssh-circ_0056686-CM) abolished CAFs-mediated proliferation, migration and apoptosis of ULM cells. CAFs-CM suppressed the expression of endoplasmic reticulum stress (ERS) marker proteins and induced the expression of extracellular matrix (ECM) marker proteins, thus suppressing ERS and increasing ECM accumulation, which could be declined by CAFssh-circ_0056686-CM. Meanwhile, knockdown of hsa_circ_0056686 reversed the inhibitory effects of CAFs-CM on brefeldin A-induced cell apoptosis. Luciferase gene reporter and RNA pull-down assays indicated that miR-515-5p directly bound with hsa_circ_0056686. MiR-515-5p overexpression restored the hsa_circ_0056686-shRNA-mediated malignant biological behaviors of ULM cells. Hsa_circ_0056686 contributed to tumor-promoting effects of CAFs in ULM, manifested by promoting ULM cell proliferation and migration and reducing ERS-induced apoptosis through sponging miR-515-5p.

Dopamine D1 receptors mediate methamphetamine-induced dopaminergic damage: involvement of autophagy regulation via the AMPK/FOXO3A pathway

RATIONALE

Clinical studies have revealed that methamphetamine abuse increases risk for developing Parkinson's diseases. It is thus important to elucidate the mechanisms by which methamphetamine damages dopaminergic neurons.

OBJECTIVES

The present study was designed to elucidate the role of the dopamine D1 receptor in methamphetamine-mediated dopaminergic neuronal damage and its underlying mechanisms.

METHODS

Mice were treated for 4 days with vehicle, methamphetamine, or the D1 agonist SKF38393 and then assessed for locomotion and performance in the pole and rotarod tests. Cellular indices of autophagy, LC3, P62, and Beclin-1, tyrosine hydroxylase, and the AMPK/FOXO3A pathway were analyzed in striatal tissue from treated mice, in PC12 cells, and in D1 receptor mutant mice.

RESULTS

Repeated treatment with a relatively high dose of methamphetamine for 4 days induced both loss of dopaminergic neurons and activation of autophagy in the striatum as evidenced by increased expression of LC3 and P62. However, such treatment did not induce either loss of dopaminergic neurons or activation of autophagy in D1 receptor knockout mice. D1 receptor-mediated activation of autophagy was also confirmed in vitro using dopaminergic neuronal PC12 cells. Further studies demonstrated that the AMPK/FOXO3A signaling pathway is responsible for D1 receptor-mediated activation of autophagy.

CONCLUSIONS

The present data indicate a novel mechanism for methamphetamine-induced dopaminergic neuronal damage and reveal an important role for D1 receptors in the neurotoxicity of this drug.