Current Drug Targets - Volume 20, Issue 2, 2019

Sexual desire includes complex motivation and drive. In the context of biological and cognitive- emotive state art of science, it is often a neglected field in medicine. In regard to the treatment, study on women's sexual function received less attention compared to the men's sexuality. In the past, this endeavor was relatively not well disseminated in the scientific community. Recently, there was a revolutionized surge of drug targets available to treat women with low sexual desire. It is timely to review the relevant biological approach, especially in the context of pharmacotherapy to understand this interesting clinical entity which was modulated by numerous interactive psychosocial inter-play and factors. The complex inter-play between numerous dimensional factors lends insights to understand the neural mechanism, i.e. the rewards centre pathway and its interaction with external psychosocialstimulus, e.g. relationship or other meaningful life events. The function of hormones, e.g. oxytocin or testosterone regulation was described. The role of neurotransmitters as reflected by the introduction of a molecule of flibenserin, a full agonist of the 5-HT1A and partial agonist of the D4 to treat premenopausal women with low sexual desire was deliberated. Based on this fundamental scientific core knowledge, we suggest an outline on know-how of introduction for sex therapy (i.e. “inner-self” and “outer-self”) where the role of partner is narrated. Then, we also highlighted on the use of pharmacological agent as an adjunct scope of therapy, i.e. phosphodiasterase-5 (PDE-5) inhibitors and hormonal treatment in helping the patient with low sexual desire.

Memories associated with substance use disorders, or substance-associated cues increase the likelihood of craving and relapse during abstinence. There is a growing consensus that manipulation of synaptic plasticity may reduce the strength of substance abuse-related memories. On the biological front, there are new insights that suggest memories associated with substance use disorder may follow unique neurobiological pathways that render them more accessible to pharmacological intervention. In parallel to this, research in neurochemistry has identified several potential candidate molecules that could influence the formation and maintenance of long-term memory. Drugs that target these molecules (blebbistatin, isradipine and zeta inhibitory peptide) have shown promise at the preclinical stage. In this review, we shall provide an overview of the evolving understanding on the biochemical mechanisms involved in memory formation and expound on the premise that substance use disorder is a learning disorder.

Kratom (Mitragyna speciosa), a naturally existing plant found in South-East Asia, is traditionally used as a herb to help elevate a person’s energy and also to treat numerous medical ailments. Other than the analgesic property, kratom has been used as an agent to overcome opioid withdrawal as it contains natural alkaloids, i.e. mitragynine, 7-hydroxymitragynine, and MGM-9, which has agonist affinity on the opioid receptors, including mu (μ) and kappa (Κ). The role of neural reward pathways linked to μ-opioid receptors and both dopaminergic and gamma-Aminobutyric acid (GABA)-ergic interneurons that express μ-opioid receptors were deliberated. However, kratom has been reported to be abused together with other illicit substances with high risk of potential addiction. There are also anecdotes of adverse effects and toxicity of kratom, i.e. tremor, fatigue, seizure, and death. Different countries have distinctive regulation and policy on the plantation and use of this plant when most of the countries banned the use of it because of its addiction problems and side effects. The aim of this review is to highlight on the potential use of kratom, unique ‘herbs” as a substitution therapy for chronic pain and opioid addiction, based on the neurobiological perspective of pain and the underlying mechanism of actions of drug addiction.

Nicotine dependence has progressively become a foremost community health interest in both the developed and developing nations due to the economic burden and health-related problems. Smoking was significantly higher among patients with schizophrenia in comparison to the general population. Nicotine dependence is not only associated with public stress, but among patients with schizophrenia, smoking brings major challenges to the management. Nicotine may diminish the therapeutic efficacy of the bioavailability of the psychopharmacological agents in-vivo. These duo perturbations, i.e. two clinical conditions co-existed may prevent psychotic symptoms remission among patients suffering from schizophrenia who smoke at the same time. The aim of this review was to highlight the role of pharmacological treatment options and strategies for patients with nicotine dependence in schizophrenia with emphasis on the underlying neurobiological process. The role of nicotine replacement therapy, i.e. norepinephrine-dopamine reuptake inhibition (NDRI) e.g. bupropion and selective partial agonist of α4β2 and full α7-nicotinic acetylcholine receptor e.g. varenicline was deliberated. An ideal choice of drug targets for patients with schizophrenia with nicotine dependence is pivotal to foster a better therapeutic alliance.

Throughout the world, antidepressants (AD) and phosphodiesterase-5 inhibitors (PDE-5i) are the commonly prescribed psychopharmacological agents for treating patients with co-morbid mental health problem and sexual dysfunction (SD). The serotonergic and noradrenergic ADs, although effective, are not without any SD adverse-effects, especially erectile dysfunction (ED). ED is a failure to obtain a satisfactory erection for rewarding sexual coitus during the phases of male's sexual arousal. It is recognized as an important reason why non-adherence to treatment was observed in patients who were on AD. AD intervention caused remission to some of the pre- treatment psychopathology of ED. However, in many patients, AD potentially magnified the unwanted sexual sideeffects. This made the situation challenging for the mental health professional. These challenges are based on the complexity of ED, its etiology and the associated risk factors, which further add to its AD side-effect. The neuro-psychopharmacological basis for AD treatment selection was deliberated. Bio-psycho-social interventions are recommended at two pivotal stages. Firstly, a step should be taken for proper assessment (e.g. detailed history, psychosocial and laboratory investigations); and identify few modifiable risk factors for ED and associated mental health issues. Secondly, with guidance of an algorithm pathway, a practical intervention should include strategies such as dose reduction, augmentation or changing to an AD with lesser or no sexual adverse-effects. It is recommended that bupropion and mirtazepine to be prescribed when patients develop adverse sexual effects with serotonin selective reuptake inhibitor (SSRI), serotonin norepinephrine reuptake inhibitor (SNRI) and tricyclic antidepressant (TCA). Few suggestions which may be borne in mind are revising sexual scripts and improving sexual techniques, life-style modifications, psychotherapy and other nonpharmacological approaches which may be beneficial to both patients and their partners.

Background: Phytoestrogens have recently been claimed to positively influence menopausal discomforts, including hot flashes. However, little is known about the influence of phytoestrogens on core body temperature during oestrogen fluctuation at menopause. Objective: Previously published findings showed that phytoestrogens could relieve menopausal complaints, thus, the present review was aimed at assessing the effects of phytoestrogens on thermoregulatory mechanism during menopausal transition. Results: The molecular mechanisms underlying hot flashes are complex. Oestrogen fluctuations cause hypothalamic thermoregulatory centre dysfunction, which leads to hot flashes during menopause. The phytoestrogens of interest, in relation to human health, include isoflavones, lignans, coumestans, and stilbenes, which are widely distributed in nature. The phytoestrogens are capable of reducing hot flashes via their oestrogen-like hormone actions. The potential effects of phytoestrogens on hot flashes and their molecular mechanisms of action on thermoregulatory centre are discussed in this review. Conclusion: The effects of phytoestrogens on these mechanisms may help explain their beneficial effects in alleviating hot flashes and other menopausal discomforts.

Human being is not spared from a broad-ranged emotional state, including being jealous. Jealousy has both affective-cognitive and behavioural-evaluative dimension where the person perceives, or experiences a real threat on a valued relationship. As this complex emotion becomes irrational and not amenable to reason, it later transforms into a dangerously ‘green-eyed monster’. This perilous situation which is viewed as pathological jealousy is a form of delusion, which is maintained by a fixed and false reasoning in an originally entrusted intimate relationship. Pathological jealousy is equally prevailing among both gender, and with a greater ubiquity among the geriatric population. The role of dopamine hyperactivity in the fronto-parietal-temporal region was implicated, with the anatomical mapping of the ventromedial prefrontal cortex (vmPFC), cingulate gyrus (CG), and amygdala involvement in the context of the disease's neurobiology. The etiology of pathological jealousy includes major psychiatric disorders, i.e. delusional disorder, schizophrenia, mood disorder, organic brain syndrome, and among others, the drug-induced psychosis. The role of relationship issues and psychodynamic perspective, i.e. psychological conflicts with dependence on a romantic partner, and low self-esteem are involved. Pathological jealousy inherits high-risk forensic psychiatry entanglement, which may warrant intensive intervention, including hospital admission and antipsychotic treatment. Treatment options include an early recognition, managing underlying neuropsychiatric disorders, psycho education, cognitive psychotherapy, and choosing an effective psychopharmacological agent. The management strategy may also resort to a geographical intervention, i.e. separation between both persons to complement the biological treatment.

Attention deficit hyperactive disorder (ADHD), a hyperactivity disorder prevalent among children may continue as an adulthood attention deficit. To date, treating an individual with an adult ADHD may be an arduous task as it involves numerous challenges, which include a need for high index of suspicion to diagnose this medical condition. Many psychiatric disorders masquerade as ADHD and delay the necessary assessment and proper treatment for this debilitating medical disorder. Adult ADHD is often misdiagnosed (or under diagnosed) due to the fact that this medical condition is being masked by the patients' high level of intellectual achievement. As the ADHD in adult persists, it may end-up with impairment in the personal-social-occupational function in which the management becomes a great challenge. The treatment of ADHD can be optimized by using various drugs targets agents like norepinephrine-dopamine reuptake inhibitor (NDRI), with or without psycho stimulants like methylphenidate, which is marketed as Ritalin. Bupropion, an NDRI has a novel effect on ADHD as the molecule exerts its effects by modulating the reward-pleasure mesolimbic dopaminergic system and at the same time regulates the elevating mood dimension of the noradrenergic neurotransmission. The role of Bupropion in the neural and psychopharmacological perspective treatment of ADHD was deliberated. The present review highlights the novel effects of Bupropion in ADHD treatment, together with the help of other successful bio-psycho-social measures. This may be of immense benefit to the psychiatrists for treating their patients.

Background: Ultrasound has been widely used in clinical diagnosis because it is noninvasive, inexpensive, simple, and reproducible. With the development of molecular imaging, material science, and ultrasound contrast agents, ultrasound-targeted delivery technology has emerged. The interaction of ultrasound and molecular probes can be exploited to change the structures of cells and tissues in order to promote the targeted release of therapeutic substances to local tumors. The targeted delivery of drugs, genes, and gases would not only improve the efficacy of tumor treatment but also avoid the systemic toxicity and side effects caused by antitumor treatments. This technology was recently applied in clinical trials and showed enormous potential for clinical application. Objective: This article briefly introduces the characteristics of the tumor microenvironment and the principle of ultrasound-targeted delivery technology. To present recent progress in this field, this review focuses on the application of ultrasound-targeted delivery technology in tumor-targeted therapy, including drug delivery, gene transfection, and gas treatment. Results: The results of this study show that ultrasound-targeted delivery technology is a promising therapeutic strategy for tumor treatment. Conclusion: Ultrasound-targeted delivery technology shows promise with regard to cancer treatment.

Background: Accumulating evidence suggests that microbiota play an important role in host's homeostasis. Thus far, researchers have mostly focused on the role of bacterial microbiota. However, human gut is a habitat for several fungal species, which produce numerous metabolites. Furthermore, various types of food and beverages are rich in a wide spectrum of fungi and their metabolites. Methods: We searched PUBMED and Google Scholar databases to identify clinical and pre-clinical studies on fungal metabolites, composition of human mycobiota and fungal dysbiosis. Results: Fungal metabolites may serve as signaling molecules and exert significant biological effects including trophic, anti-inflammatory or antibacterial actions. Finally, research suggests an association between shifts in gut fungi composition and human health. Changes in mycobiota composition have been found in obesity, hepatitis and inflammatory bowel diseases. Conclusion: The influence of mycobiota and dietary fungi on homeostasis in mammals suggests a pharmacotherapeutic potential of modulating the mycobiota which may include treatment with probiotics and fecal transplantation. Furthermore, antibacterial action of fungi-derived molecules may be considered as a substitution for currently used antibacterial agents and preservatives in food industry.

Adult mammalian cardiomyocytes (CMs) exhibit limited proliferative capacity, as cell cycle activity leads to an increase in DNA content, but mitosis and cytokinesis are infrequent. This makes the heart highly inefficient in replacing with neoformed cardiomyocytes lost contractile cells as occurs in diseases such as myocardial infarction and dilated cardiomyopathy. Regenerative therapies based on the implant of stem cells of diverse origin do not warrant engraftment and electromechanical connection of the new cells with the resident ones, a fundamental condition to restore the physiology of the cardiac syncytium. Consequently, there is a growing interest in identifying factors playing relevant roles in the regulation of the CM cell cycle to be targeted in order to induce the resident cardiomyocytes to divide into daughter cells and thus achieve myocardial regeneration with preservation of physiologic syncytial performance. Despite the scientific progress achieved over the last decades, many questions remain unanswered, including how cardiomyocyte proliferation is regulated during heart development in gestation and neonatal life. This can reveal unknown cell cycle regulation mechanisms and molecules that may be manipulated to achieve cardiac self-regeneration. We hereby revise updated data on CM cell cycle regulation, participating molecules and pathways recently linked with the cell cycle, as well as experimental therapies involving them.