Repetitive, mild traumatic brain injury results in a progressive white matter pathology, cognitive deterioration, and a transient gut microbiota dysbiosis.

Traumatic brain injury (TBI) is often accompanied by gastrointestinal and metabolic disruptions. These systemic manifestations suggest possible involvement of the gut microbiota in head injury outcomes. Although gut dysbiosis after single, severe TBI has been documented, the majority of head injuries are mild, such as those that occur in athletes and military personnel exposed to repetitive head impacts.

Abuse potential and toxicity of the synthetic cathinones (i.e., "Bath salts").

The synthetic cathinones are derived from the naturally occurring drug cathinone found in the khat plant (Catha edulis) and have chemical structures and neurochemical consequences similar to other psychostimulants. This class of new psychoactive substances (NPS) also has potential for use and abuse coupled with a range of possible adverse effects including neurotoxicity and lethality. This review provides a general background of the synthetic cathinones in terms of the motivation for and patterns and demographics of their use as well as the behavioral and physiological effects that led to their spread as abused substances and consequent regulatory control.

Dissociation between hypothermia and neurotoxicity caused by mephedrone and methcathinone in TPH2 knockout mice.

Rationale: Mephedrone is a commonly abused constituent of "bath salts" and has many pharmacological effects in common with methamphetamine. Despite their structural similarity, mephedrone differs significantly from methamphetamine in its effects on core body temperature and dopamine nerve endings. The reasons for these differences remain unclear.

Assessing the role of dopamine in the differential neurotoxicity patterns of methamphetamine, mephedrone, methcathinone and 4-methylmethamphetamine.

Methamphetamine and mephedrone are designer drugs with high abuse liability and they share extensive similarities in their chemical structures and neuropharmacological effects. However, these drugs differ in one significant regard: methamphetamine elicits dopamine neurotoxicity and mephedrone does not. From a structural perspective, mephedrone has a β-keto group and a 4-methyl ring addition, both of which are lacking in methamphetamine.

The Role of Brain-Derived Neurotrophic Factor in the Pathophysiology of Psychiatric and Neurological Disorders.

Brain-derived neurotrophic factor (BDNF) is a neurotrophin highly expressed in the brain with a potent influence on several aspects of neuronal function. Since its discovery in the early 1980s, BDNF has prompted a great interest in better understanding its physiological role and has been established as the main central neurotrophic factor. BDNF is initially synthesized as a precursor, pro-BDNF, which is then cleaved to form mature BDNF (m-BDNF).

Dissecting the Influence of Two Structural Substituents on the Differential Neurotoxic Effects of Acute Methamphetamine and Mephedrone Treatment on Dopamine Nerve Endings with the Use of 4-Methylmethamphetamine and Methcathinone.

Mephedrone (MEPH) is a -ketoamphetamine stimulant drug of abuse that is often a constituent of illicit bath salts formulations. Although MEPH bears remarkable similarities to methamphetamine (METH) in terms of chemical structure, as well as its neurochemical and behavioral effects, it has been shown to have a reduced neurotoxic profile compared with METH. The addition of a -keto moiety and a 4-methyl ring substituent to METH yields MEPH, and a loss of direct neurotoxic potential.

Neurotoxicology of Synthetic Cathinone Analogs.

The present review briefly explores the neurotoxic properties of methcathinone, mephedrone, methylone, and methylenedioxypyrovalerone (MDPV), four synthetic cathinones most commonly found in "bath salts." Cathinones are β-keto analogs of the commonly abused amphetamines and display pharmacological effects resembling cocaine and amphetamines, but despite their commonalities in chemical structures, synthetic cathinones possess distinct neuropharmacological profiles and produce unique effects. Among the similarities of synthetic cathinones with their non-keto analogs are their targeting of monoamine systems, the release of neurotransmitters, and their stimulant properties.

Brain serotonin signaling does not determine sexual preference in male mice.

It was reported recently that male mice lacking brain serotonin (5-HT) lose their preference for females (Liu et al., 2011, Nature, 472, 95-100), suggesting a role for 5-HT signaling in sexual preference. Regulation of sex preference by 5-HT lies outside of the well established roles in this behavior established for the vomeronasal organ (VNO) and the main olfactory epithelium (MOE).

3,4-Methylenedioxypyrovalerone prevents while methylone enhances methamphetamine-induced damage to dopamine nerve endings: β-ketoamphetamine modulation of neurotoxicity by the dopamine transporter.

Methylone, 3,4-methylenedioxypyrovalerone (MDPV), and mephedrone are psychoactive ingredients of 'bath salts' and their abuse represents a growing public health care concern. These drugs are cathinone derivatives and are classified chemically as β-ketoamphetamines. Because of their close structural similarity to the amphetamines, methylone, MDPV, and mephedrone share most of their pharmacological, neurochemical, and behavioral properties.

MDMA increases glutamate release and reduces parvalbumin-positive GABAergic cells in the dorsal hippocampus of the rat: role of cyclooxygenase.

3,4-Methylenedioxymethamphetamine (MDMA; Ecstasy) is a popular drug of abuse with well-documented acute effects on serotonergic, dopaminergic, and cholinergic transmitter systems, as well as evidence of long-term disruption of serotoninergic systems in the rat brain. Recently, it was demonstrated that MDMA evokes a delayed and sustained increase in glutamate release in the hippocampus. The purpose of the present study was to determine the role of inflammatory mediators in the MDMA-induced increase in glutamate release, as well as the contribution of inflammatory pathways in the persistent neurochemical toxicity associated with repeated MDMA treatment.

MDMA produces a delayed and sustained increase in the extracellular concentration of glutamate in the rat hippocampus.

The neurochemical effects of MDMA (3,4-methylenedioxymethamphetamine) on monoaminergic and cholinergic systems in the rat brain have been well documented. However, little is known regarding the effects of MDMA on glutamatergic systems in the brain. In the present study the effects of multiple injections of MDMA on extracellular concentrations of glutamate in the striatum, prefrontal cortex, and dorsal hippocampus were examined.