Nandrolone improve synaptic plasticity at the hippocampus CA1 area and spatial localization in the Morris water maze of male adolescent rats

Major adverse cardiovascular events associated with testosterone treatment: a pharmacovigilance study of the FAERS database

Background and purpose: Testosterone is an essential sex hormone in maintaining masculine characteristics, which is prescribed for male hypogonadism as testosterone replacement treatment (TRT). Herein, we investigated long-standing controversies about the association between TRT and major adverse cardiovascular events (MACEs), based on real world adverse event (AE) reports, registered in the Food and Drug Administration Adverse Event Reporting System (FAERS). Methods: Publicly available FAERS data from 1 January 2004 to 31 December 2022 were retrieved from the Food and Drug Administration (FDA) website. The data mining protocol including the reporting odds ratio (ROR) and the Bayesian confidence propagation neural network (BCPNN) was applied to analyze overreporting caused by risk factors and MACEs, including TRT, morbidities, and ages. The ROR and the BCPNN were also applied to investigate the annually developing trend of pharmacovigilance (PV) signals in the real world, retrospectively. Results: A total of 3,057 cases referring to MACEs, with a median age of 57 years old (yo), were identified from 28,921 cases of testosterone users. MACEs related to PV signals have emerged since 2014, including cardiac death, non-fatal myocardial infarction, and non-fatal stroke. Myocardial infarction (MI) (ROR: 9.46; IC₀₂₅: 3.08), acute myocardial infarction (AMI) (ROR: 16.20; IC₀₂₅: 3.72), ischemic cardiomyopathy (ROR: 11.63; IC₀₂₅: 2.20), and cardiomyopathy (ROR: 5.98; IC₀₂₅: 1.96) were the most significant signals generated, and weaker signals included cardiac failure acute (ROR: 4.01; IC₀₂₅: 0.71), cardiac arrest (ROR: 1.88; IC₀₂₅: 0.56), and ventricular fibrillation (VF) (ROR: 2.38; IC₀₂₅: 0.38). The time-to-onset (TTO) of MACEs was calculated with a median of 246 days for AMI. Conclusion: For myocardial infarction and cardiomyopathy, TRT statistically tended to increase the risk of MACEs, while for cardiac arrhythmia, cardiac failure, and stroke, TRT demonstrated beneficial effects among the population with morbidities, such as testosterone deficiency (TD), diabetes mellitus (DM), and hypertension. MACEs were rare but led to serious outcomes including significant increase in death and disability. Since 2018, and before 2014, reports referring to TRT associated with MACEs were relatively scarce, which indicated that there might be a considerable number of cases that went unrecorded, due to neglection. Health workers and testosterone users might pay more attention to testosterone-induced MACEs.

Adolescent morphine exposure impairs dark avoidance memory and synaptic potentiation of ventral hippocampal CA1 during adulthood in rats

Adolescence is a neurobiological critical period for neurodevelopmental processes. Adolescent opioid exposure can affect cognitive abilities via regional-specific lasting changes in brain structure and function. The current study was therefore designed to assess the long-term effects of adolescent morphine exposure on dark avoidance memory and synaptic plasticity of the ventral hippocampal CA1. Adolescent Wistar rats received escalating doses of morphine for 10 days. Morphine injections were started with an incremental dose of 2.5 mg/kg to reach a dose of 25 mg/kg. 30 days after the last injection, inhibitory memory and in vitro field potential recording were evaluated. Also, the weight of the animals was measured during drug and post-drug exposure. We found that adolescent morphine exposure decreased weight gain during morphine and post-morphine exposure. Passive avoidance memory was impaired in the morphine group. Moreover, adolescent morphine exposure caused an increase in baseline synaptic responsiveness and failed long-term potentiation (LTP) in the ventral hippocampal CA1 during adulthood. In the morphine group, the mean values of the field excitatory postsynaptic potential (fEPSP) slopes required to elicit a half-maximal population spike (PS) amplitude were significantly greater than that of the saline group. Therefore, adolescent morphine exposure has a durable effect on memory functions, synaptic activity, and plasticity of ventral hippocampal CA1. Adults with adolescent morphine exposures may experience maladaptive behaviors and cognitive disabilities.

Experimental studies on androgen administration in animal models: current and future perspectives

PURPOSE OF REVIEW

This review aims to report the most recent (2020-2022) experimental scientific studies conducted on animal models, in order to highlight the relevant findings on the adverse effects related to androgen administration.

RECENT FINDINGS

Forty-one studies published between January 2020 and July 2022 were selected. The majority of studies investigated the effects of one androgen, whereas only four studies analyzed the effects of two drugs. Nandrolone decanoate was the most investigated drug (20 articles), boldenone was tested in 8 articles, testosterone and stanozolol were used in 7 articles each, 17b-trenbolone, metandienone, and oxandrolone were tested in 1 article each. The articles clarify the adverse effects of androgen administration on the heart, brain, kidney, liver, reproductive and musculoskeletal systems.

SUMMARY

The main findings of this review highlight that androgen administration increases inflammatory mediators, altering different biochemical parameters. The results concerning the reversibility of the adverse effects are controversial: on the one hand, several studies suggested that by stopping the androgen administration, the organs return to their initial state; on the other hand, the alteration of different biochemical parameters could generate irreversible organ damage. Moreover, this review highlights the importance of animal studies that should be better organized in order to clarify several important aspects related to androgen abuse to fill the gap in our knowledge in this research field.

Impairment of spatial memory and dorsal hippocampal synaptic plasticity in adulthood due to adolescent morphine exposure

Opioid exposure during adolescence, a crucial period of neurodevelopment, has lasting neurological and behavioral consequences and affects the cognitive functions in adulthood. This study investigated the effects of adolescent morphine exposure in spatial learning and memory and synaptic plasticity of the CA1 area of the dorsal hippocampus. Adolescent Wistar rats received increasing doses of morphine for 1, 5, and 10 days. Acute morphine group was injected 2.5 mg/kg morphine for 1 day, subchronic morphine group for 5 days, with an increasing dose of 2.5 mg/kg and reached to the dose of 12.5 mg/kg and chronic morphine group for 10 days that began with an increasing dose of 2.5 mg/kg and reached to the dose of 25 mg/kg. Then after 25 days and reaching adulthood, spatial learning and memory were evaluated via the Morris water maze (MWM) test. Moreover, we test the electrophysiological properties of dorsal hippocampal plasticity in adult rats by in vitro field potential recordings. Subchronic and chronic adolescent morphine exposure impaired spatial learning and memory in the MWM test. Baseline synaptic responses in the chronic morphine group were increased and long-term potentiation (LTP) impaired in the CA1 area in subchronic and chronic morphine groups. In adulthood, the slope of the field excitatory postsynaptic potential (fEPSP) required to elicit a half-maximal population spike (PS) amplitude was significantly larger in subchronic and chronic adolescent morphine exposure compared to the saline group. Therefore, subchronic and chronic adolescent morphine exposure altered synaptic transmission and plasticity in addition to learning and memory. Long-term morphine exposure during adolescence can interfere with neurodevelopment, making a persistent impression on plasticity and cognitive capability in adulthood.

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

BACKGROUND AND AIM

In recent years the expanding misuse of Nandrolone among non-athletes, particularly adolescent males is a prevalent global concern due to its adverse effects. This article provides a summary of the experimental studies to clarify the relationship between Nandrolone exposure and behavioral and cognitive performances.

MATERIALS AND METHODS

The present systematic review was conducted using PubMed, Embase and ScienceDirect databases, from 2000 to 2020, using the following key terms: Nandrolone AND Cognition, Nandrolone AND Learning, Nandrolone AND Memory, Nandrolone AND (Synaptic plasticity or Hippocampal synaptic plasticity), Nandrolone AND (Aggression or Aggressive-like behavior), Nandrolone AND (Anxiety or Anxiety-like behavior), Nandrolone AND (Depression or Depressive-like behavior).

RESULTS

33 qualified papers were selected from the 2498 sources found. Of the 33 cases, 32 (96.97%) were males while only 1 (3.03%) was female and male. From 33 selected articles 8 reported studies were related to spatial memory, 2 reported studies were related to avoidance memory, 11 studies reported information on synaptic plasticity, 11 reported studies were related to aggressive behavior, 8 reported studies were related to aggressive behavior and 6 reported studies were related to depression.

CONCLUSION

Nandrolone can change spatial ability, avoidance memory and hippocampal synaptic plasticity. Also, Nandrolone exposure produces variable effects on behavioral function such as aggression, depression and anxiety. This despite the fact that the results are contradictory. These discrepancies might be due to the differences in sex, age, dosage and treatment duration, and administration route. However, the negative results are more common than the published positive ones.

Astaxanthin Attenuates Neuroinflammation in Status Epilepticus Rats by Regulating the ATP-P2X7R Signal

Background

As a life-threatening neurological emergency, status epilepticus (SE) is often refractory to available treatment. Current studies have shown a causal role of neuroinflammation in patients with lower seizure thresholds and driving seizures. The ATP-gated purinergic P2X7 receptor (P2X7R) is mainly expressed on the microglia, which function as gatekeepers of inflammation. Although emerging evidence has demonstrated significant anti-inflammatory effects of astaxanthin (AST) in SE, the associated mechanism remains unclear. Therefore, this study aimed to clarify the effects of AST on P2X7R-related inflammation in SE.

Methods

SE was induced in rats using lithium–pilocarpine, and AST was administered 1 h after SE induction. Rat microglia were treated with lipopolysaccharide (LPS), AST, ATP, 2,3-O-4-benzoyl-4-benzoyl-ATP (BzATP) and oxidized ATP (oxATP). The Morris water maze, immunohistochemistry, and Nissl staining were performed in rats. Expressions of P2X7R and inflammatory cytokines (such as cycloxygenase-2 (Cox-2), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α)) were detected using real-time polymerase chain reaction (RT-PCR) and Western blot (WB) both in rats and microglia. ATP concentration in the microglia was evaluated using ELISA.

Results

The AST alleviated hippocampal injury and improved cognitive dysfunction induced by SE. AST also effectively inhibited inflammation and downregulated P2X7R expression in both rat brain and microglia. The results also showed that AST reduced the extracellular ATP levels and that P2X7R expression could be increased by extracellular ATP. In addition, BzATP upregulates the expression of P2X7R and inflammatory factors in microglia. Conversely, it downregulates the expression of P2X7R and inflammatory factors.

Conclusion

Our study suggests that AST attenuated ATP-P2X7R mediated inflammation in SE.