Alpha-PVP induces the rewarding effect via activating dopaminergic neuron

Paternal methamphetamine exposure differentially affects first and second generations in mice

Amphetamine-type stimulants are abused worldwide, and methamphetamine (METH) accounts for a large majority of seized abused drug cases. Recently, the paternal origin of health and disease theory has been proposed as a concept wherein paternal factors influence descendants. Although METH abuse is more common among males, its effects on their descendants were not examined. Therefore, we investigated the effects of paternal METH exposure on F1 and F2 levels in a mouse model. Sires were administered METH for 21 days and mated with female mice to obtain F1 mice. Growth evaluations (number of births, survival rate, body weight, righting reflex, cliff avoidance tests, and wire-hanging maneuver) were performed on F1 mice. Upon reaching six weeks of age, the mice were subjected to spontaneous locomotion, elevated plus-maze, acute METH treatment, and passive avoidance tests. Additionally, RNA-seq was performed on the striatum of male mice. Male F1 mice were mated with female mice to obtain F2 mice. They were subjected to the same tests as the F1 mice. Paternal METH exposure resulted in delayed growth and decreased memory function in F1 mice, overweight in F2 mice, decreased METH sensitivity, and reduced anxiety-related behaviors in female F2 mice. Enrichment analysis revealed significant enrichment of terms related to behavior in F1 and protein folding in F2. These results indicated that the effects of paternal METH exposure vary across generations. The effects of paternal factors need to be examined not only in F1, but also in F2 and beyond.

Toxicokinetic evaluation during intoxication of psychotropic drugs using brain microdialysis in mice

In the event of an overdose, the pharmacokinetics of the drug may be altered, resulting in an unexpectedly rapid increase in blood and tissue drug concentrations. Because central nervous system (CNS)-acting drugs are the major cause of hospitalization for overdose, brain concentrations, which are closely related to the development of acute psychotropic symptoms, would be important. However, due to the lack of an appropriate model for overdose, it is difficult to predict the CNS symptoms of patients with acute poisoning. To clarify the toxicokinetics during intoxication with CNS-acting drugs, we investigated the relationship between the dose and concentrations in the blood and brain in mice. Therapeutic or toxic doses of phenobarbital, flunitrazepam, imipramine, and amoxapine were administered intraperitoneally to mice. Serum and extracellular fluid of the brain were collected up to 24 hr after administration and analyzed using LC-MS/MS to determine the pharmacokinetic parameters in the serum and brain. A comparison of the four psychotropic drugs showed that the toxicokinetics of amoxapine in the blood and brain are clearly different from others, with the brain concentrations being specifically highly susceptible to increase during dose escalation. These results are consistent with the CNS-related symptoms observed in amoxapine overdose. Therefore, the methodology of the current study could be useful for predicting CNS toxicity during psychotropic drug poisoning.

Mechanism of Dopaminergic Nerve Transmission in Different Doses of Morphine Addiction and Stress-Induced Depression

Depression not only threatens the health and quality of life of patients but also brings a huge mental and economic burden to the patients' families. This paper mainly studies the mechanism of dopaminergic neurotransmission in different doses of morphine addiction and stress-induced depression. In the experiment, 40 male SD rats were selected. The experiment established a rat model of chronic stress depression. The rats used in this model are all raised in a single cage, and there will be various stimuli every day for 21 days, but high-intensity continuous stimuli must be avoided, and the same stimuli will not appear continuously. The experiment established a depression animal model through chronic unpredictable mild stress (CUMS), combined with the conditioned position preference (CPP) model of morphine addiction to detect the establishment of CPP in such animals, so as to explore certain stress stimuli or depression, the influence on morphine addiction, and the relationship between them. The second or third branches of pyramidal neurons were selected to analyze the PL and CA3 regions. When analyzing the density of dendrites, each animal selected at least 8 dendrites in order to count the number of dendrites and selected a length of 20 μm on each branch to record the number of dendrites. All measured values are expressed as average ± standard deviation and analyzed by SPSS17.0 statistical software, and Levene test is used in the scattered consistency test. The average NIV of PEN before injection was 11.92 ± 2.90 Hz, and the average latency was 0.16 ± 0.03 s. The results indicate that CUMS may reduce the conditioned learning and memory ability by damaging the learning loop, rather than affecting the reward loop to weaken the establishment of morphine-dependent CPP.

Synthetic cathinone self-administration in female rats modulates neurotransmitter levels in addiction-related brain regions

Synthetic cathinones are used for their stimulant-like properties. Stimulant-induced neurochemical changes are thought to occur at different times in different brain regions and neurotransmitter systems. This study sought to examine the behavioral and neurochemical effects of α-pyrrolidinopentiophenone (α-PVP) and mephedrone (4MMC) in female rats. Methods probed the chronology of effects of synthetic cathinone exposure. Female rats were trained to self-administer α-PVP, 4MMC, or saline. Drug exposure ceased after 7 days of autoshaping for half of each drug group; the other half self-administered for another 21 days. Amygdala, hippocampus, hypothalamus, PFC, striatum, and thalamus were extracted, and tissue was analyzed with electrochemical detection and liquid chromatography mass spectrometry. Responding was minimal during autoshaping; thus, most infusions were delivered noncontingently in the autoshaping phase. Rats acquired self-administration of α-PVP and 4MMC. Synthetic cathinone administration, and duration of exposure produced several effects on neurotransmitters. α-PVP primarily increased serotonin, 5-hydroxy-3-acetic acid (5-HIAA), norepinephrine, and glutamate in hypothalamus. In contrast, 4MMC decreased serotonin and 5-HIAA in several brain regions. Longer durations of exposure to both synthetic cathinones increased 5-HIAA, norepinephrine, and glutamate in multiple brain regions compared to the short exposure during autoshaping. Notably, both α-PVP and 4MMC produced minimal changes in dopamine levels, suggesting that the dopaminergic effects of these synthetic cathinones are transient. These alterations in neurotransmitter levels indicate that synthetic cathinone use may produce differential neurochemical changes during the transition from use to abuse.

Simultaneous profiling of organic and inorganic impurities in α-pyrrolidinopentiophenone (α-PVP)

Abuse of recreational drugs (i.e., synthetic chemicals with the structure or expected neurotropic effects, or both, similar to those of controlled substances) is a serious and continuous social harm. Designer drugs are often manufactured or synthesized in small-scale clandestine laboratories with impure starting materials, poor handling skills and inferior storage conditions. Therefore, in addition to the objective compound, diverse impurities may be present, for example, from the starting material, intermediates, catalytic metals formed during chemical synthesis, and materials from the environment. Impurity profiling of drug seizures is a useful scientific tool to obtain information on the clandestine manufacturers and drug trafficking networks. 1-Phenyl-2-(1-pyrrolidinyl)-1-pentanone (α-PVP), a novel psychoactive substance of the cathinone type that is banned in many countries, is still supplied and distributed within the illicit drug market. By using GC-MS and ICP-MS, we identified and estimated the relative contents of organic and inorganic impurities in the bulk powder of 15 batches of α-PVP. We then conducted multivariate data analyses to reveal characteristic patterns of the profiles. Hierarchical cluster analysis of both the organic and inorganic impurities revealed two groups that showed similar impurity profiles, which suggested that the batches in these groups were synthesized in similar routes under similar synthetic environments. The initial groups revealed by the organic impurities were further divided when combined with the data from the inorganic impurities. The present study, therefore, demonstrated the effectiveness of integrated analyses of organic and inorganic impurities for the accurate clustering of designer drugs, to provide precise information to drug investigation authorities.

Dopaminergic impact of cART and anti-depressants on HIV neuropathogenesis in older adults

The success of combination antiretroviral therapy (cART) has transformed HIV infection into a chronic condition, resulting in an increase in the number of older, cART-treated adults living with HIV. This has increased the incidence of age-related, non-AIDS comorbidities in this population. One of the most common comorbidities is depression, which is also associated with cognitive impairment and a number of neuropathologies. In older people living with HIV, treating these overlapping disorders is complex, often creating pill burden or adverse drug-drug interactions that can exacerbate these neurologic disorders. Depression, NeuroHIV and many of the neuropsychiatric therapeutics used to treat them impact the dopaminergic system, suggesting that dopaminergic dysfunction may be a common factor in the development of these disorders. Further, changes in dopamine can influence the development of inflammation and the regulation of immune function, which are also implicated in the progression of NeuroHIV and depression. Little is known about the optimal clinical management of drug-drug interactions between cART drugs and antidepressants, particularly in regard to dopamine in older people living with HIV. This review will discuss those interactions, first examining the etiology of NeuroHIV and depression in older adults, then discussing the interrelated effects of dopamine and inflammation on these disorders, and finally reviewing the activity and interactions of cART drugs and antidepressants on each of these factors. Developing better strategies to manage these comorbidities is critical to the health of the aging, HIV-infected population, as the older population may be particularly vulnerable to drug-drug interactions affecting dopamine.