Association between nandrolone and behavioral alterations: A systematic review of preclinical studies

Adenosine receptors participate in anabolic-androgenic steroid-induced changes on risk assessment/anxiety-like behaviors in male and female rats

Anabolic-androgenic steroids (AAS) and caffeine can induce several behavioral alterations in humans and rodents. Administration of nandrolone decanoate is known to affect defensive responses to aversive stimuli, generally decreasing inhibitory control and increasing aggressivity but whether caffeine intake influences behavioral changes induced by AAS is unknown. The present study aimed to investigate behavioral effects of caffeine (a non-selective antagonist of adenosine receptors) alone or combined with nandrolone decanoate (one of the most commonly AAS abused) in female and male Lister Hooded rats. Our results indicated that chronic administration of nandrolone decanoate (10 mg/kg, i.m., once a week for 8 weeks) decreased risk assessment/anxiety-like behaviors (in the elevated plus maze test), regardless of sex. These effects were prevented by combined caffeine intake (0.1 g/L, p.o., ad libitum). Overall, the present study heralds a key role for caffeine intake in the modulation of nandrolone decanoate-induced behavioral changes in rats, suggesting adenosine receptors as candidate targets to manage impact of AAS on brain function and behavior.

Activation of androgen receptors alters hippocampal synaptic plasticity and memory retention through modulation of L-type calcium channels

AIMS

It has been revealed that membrane androgen receptor activation modulates avoidance memory and synaptic plasticity. In a previous study, we showed that Calcineurin, a calcium dependent phosphatase, could be a potential mediator of these AR effects. Also, it is reported that AR activation leads to L-type calcium channel activation. The aim of the current study is to test whether L-type calcium channels are downstream of AR and whether this signal pathway mediates the impairment effect of androgenic steroids on passive avoidance memory and synaptic plasticity.

MATERIALS AND METHODS

We measured the effect of Nandrolone Decanoate (AR agonist), AR antagonist (Nilutamide) plus ND or L-type calcium channel inhibitor (Nifedipine) plus ND on passive avoidance performance of adolescent male rats. For extracellular field potential recordings hippocampal slices were perfused with ND, Nilutamide-ND or Nifedipine-ND.

KEY FINDINGS

Our results clarified that AR activation by ND could impair avoidance behavior as step through latency decreased in ND-treated group while application of both Nilutamide and Nifedipine reestablished normal avoidance behavior. Also, LTP induction in the CA1 area of hippocampus was diminished by ND perfusion and both AR antagonist and L-type calcium channel inhibitor application lead to normal LTP. These findings support our hypothesis that activation of L-type calcium channels are involved in ARs mechanism effects on both avoidance behavior and hippocampal synaptic plasticity.

SIGNIFICANCE

Understanding the biological effects of AR agonists on cognitive processes and its cellular mechanism may be a new/supplementary way to treating fear-related disorders.

Association between neuronal degeneration and supraphysiological doses of two types of anabolic steroids in rat brain

The anabolic androgenic steroids (AAS) are natural compounds that are precursors or derivatives of testosterone and, as a consequence of indiscriminate use, cause irreversible neuronal effects. For this study, 70 brain samples were used from male Wistar rats, separated into 14 groups, divided into: control, sedentary, and exercise groups; in the concentrations: 5 mg, 10 mg, and 15 mg. Two different AAS were used: Testosterone Cypionate (TC) and Nandrolone Decanoate (ND). The encephali followed all the conventional histological procedures, for further analysis of the estimates of neuron bodies of the Locus coeruleus; also being carried out the techniques of the Tunnel Assay and Von Kossa staining. The results obtained show significant values different from the control group: Testosterone Cypionate (TCS): 5 mg (25,00 ± 4,47); 10 mg (23,67 ± 4,45) and 15 mg (21,93 ± 5,65), as well as for Nandrolone Decanoate (ND) in the doses: 5 mg (23,40 ± 3,81); 10 mg (22,80 ± 3,80) and 15 mg (22,80 ± 4,54) being the values of the control group (CGS) 34,27 ± 6,06. For the groups that exercised, the values were: TCT 5 mg 20,87 ± 3,23; TCT 10 mg 21,93 ± 4,91 and TCT 15 mg 21,47 ± 4,36 while, the Nandrolone Decanoate (ND) groups, in the different doses were: NDT 5 mg 21,53 ± 4,34; NDT 10 mg 23,53 ± 1,68 and NDT 15 mg 23,40 ± 2,20, also expressing significant values different from the control group. When comparing the sedentary control group with the animals that exercised, a statistically significant difference was observed being: CGS 34,27 ± 6,06; TCT 5 mg; 20,87 ± 3,23; NDT 5 mg 21,53 ± 4,34; TCT 10 mg 21,93 ± 4,91; NDT 10 mg 23,53 ± 1,68; TCT 15 mg 21,47 ± 4,36 and NDT 15 mg 23,40 ± 2,20. The results of this study, point out that both steroids drastically reduce neuronal density in the Locus coeruleus area inferring that, the possible cause of neuronal death is necrosis, caused by intracellular calcium imbalance.