Gepirone hydrochloride: a novel antidepressant with 5-HT1A agonistic properties

Depression is a neuropsychiatric disorder that affects more than 350 million people all over the world. There are psychological and pharmacological treatments for depression which mainly focus on monoaminergic neurotransmission theory. The main concern regarding available antidepressants is the lag period and other side effects, such as sexual dysfunction. Gepirone is a drug of the azapirone group which is a 5-HT1A receptor agonist belonging to the buspirone family. Gepirone is under clinical development and has been shown to be more effective than selective serotonin reuptake inhibitors (SSRIs), as this drug treats the psychiatric disorders without causing sexual dysfunction, which limits the use of SSRIs. It possesses greater selectivity for the 5-HT1A receptor than SSRIs. Clinical studies have shown that gepirone has differential action at pre- and postsynaptic 5-HT1A receptors. Gepirone extended-release tablets (gepirone ER, Travivo) showed promising effects in adult outpatients for the treatment of major depressive disorder (MDD) in a double-blind, randomized, placebo-controlled clinical study. Gepirone also showed an antianxiety effect in a placebo-controlled trial in generalized anxiety disorder. Absorption of gepirone is increased when administered with food as there is no substantial change in Cmax and half-life but it significantly increases AUC and mean residence time. Gepirone undergoes first-pass metabolism and its major metabolites are 1- (2-pyrimidinyl)-piperazine (1-PP) and 3-OH-gepirone, both of which are pharmacologically active. In addition to its better efficacy, gepirone is well tolerated and the major adverse effects observed have been nausea, dizziness and lightheadedness. Evidence from preclinical and clinical studies revealed that gepirone could be a breakthrough therapeutic agent in the treatment of anxiety and MDD.

Lumateperone: a new treatment approach for neuropsychiatric disorders

Lumateperone tosylate (ITI-007 tosylate, ITI-722) is a first-in-class investigational drug which acts syn-ergistically through multiple systems (serotonergic, dopaminergic and glutamatergic), thus representing a unique approach for the therapeutic management of a range of neuropsychiatric disorders. It possesses a potent antagonistic activity at 5-hydroxytryptamine (serotonin) 2A (5-HT2A) receptors and also binds to dopamine (D1, D2) receptors with partial agonism at presynaptic D2 receptors and postsynaptic antagonism. Further, preclinical data demonstrated that lumateperone uniquely acts as an indirect modulator of glutamatergic phosphoprotein with D1-dependent augmentation of both NMDA and AMPA activity via the mammalian target of rapamycin (mTOR) pathway, mechanisms thought to predict potent and rapid antidepressant effects. Previous results of schizophrenia efficacy studies found robust improvements in depressive as well as psychotic symptoms for those patients who were comorbidly depressed. In various clinical trials to date, the safety profile of lumateperone was found to be similar to that of placebo. These promising results and strong performance in phase II studies point to the potential of lumateperone to display potent and rapid antidepressant effects in patients suffering from a range of mood disorders. Currently, this novel drug is in phase III of its clinical development for schizophrenia, agitation associated with dementia and bipolar depression.

Targeting Kynurenine Pathway in Olfactory Bulbectomised Mice: Inflammatory and Neurodegerative Pathway of Depression

Aims and objectives

The aim of study was to evaluate the pharmacotherapeutic efficacy of NDGA in experimental paradigm of depression i.e. olfactory bulbectomy (OB) specifically targeting kynurenine pathway.

Materials and method

Depression like behaviours was induced in OB mice and evaluated by assessment of various behavioural (olfactory deficit test, forced swim test, splash test, open field test, sucrose preference test), biochemical (catalase, reduced glutathione, SOD, nitrite, MAO-A, MDA, corticosterone), inflammatory cytokines (TNF- α, IL-1β, IL-6, IFN-γ) levels and alterations in delta sleep was recorded using EEG. Kynurenine pathway metabolites were determined in plasma and brain using HPLC method. After 14 days post-surgery, olfactory bulbectomized (OBX) mice were administered nordihydroguaiaretic acid (5 mg/kg, 10 mg/kg and 25 mg/kg) daily i.p.

Results

We have developed a new HPLC method for simultaneous estimation of monoamines and kynurenine pathway metabolites in plasma and brain samples of mice. Chronic treatment with nordihydroguaiaretic acid significantly restored all behavioural, biochemical and neurochemical alterations in OBX mice and increase in quinolinic acid and decrease in kynurenic acid point out the neurodegeneration hypothesis of depression.

Conclusion

Nordihydroguaiaretic acid showed potent neuropharmacotherapeutic effect in OBX mice by virtue of its strong anti-oxidant, anti-inflammatory, anti-stress and by restoring quinolinic acid levels.

Curcumin loaded solid lipid nanoparticles ameliorate adjuvant-induced arthritis in rats

BACKGROUND

Rheumatoid arthritis (RA), a chronic and systemic inflammation, results in destruction of joints and cartilages. Effectiveness of curcumin has been established in a wide variety of inflammatory disorders, but its utility as a therapeutic agent is limited by its poor absorption, rapid metabolism and fast systemic elimination. To apprehend these limitations, we propose to use highly bioavailable curcumin loaded solid lipid nanoparticles (C-SLNs) for the treatment of RA.

METHODS

In the present study, the protective effect of curcumin and its SLNs was evaluated in complete Freund's adjuvant (CFA)-induced arthritis in rats.

RESULTS

Arthritic rats exhibited marked decrease in paw withdrawal threshold in Randall-Selitto and von Frey hair test along with decreased reaction time in hot plate. Arthritic rats also showed significant joint hyperalgesia, joint stiffness and increased paw volume along with marked decrease in mobility score. Arthritic rats showed a significant increase in blood leukocyte count, oxidative-nitrosative stress, tumour necrosis factor-α, C-reactive protein, cyclic citrullinated peptide antibody levels and radiological alterations in tibiotarsal joint. C-SLN administration (10 and 30 mg/kg), when compared with free curcumin (10 and 30 mg/kg), significantly and dose dependently ameliorated various symptoms of arthritis in rats, improved biochemical markers and preserved radiological alterations in joints of arthritic rats.

CONCLUSIONS

The current findings suggest the protective potential of curcumin-SLNs in ameliorating CFA-induced arthritis in rats through attenuation of oxido-inflammatory and immunomodulatory cascade. Further, the results emphasize that SLNs are a novel approach to deliver curcumin into the inflamed joints and improve its biopharmaceutical performance.

Role of Lactobacillus acidophilus loaded floating beads in chronic fatigue syndrome: behavioral and biochemical evidences

BACKGROUND

  In recent years the interface between neuropsychiatry and gastroenterology has converged in to a new discipline referred to as enteric neuroscience. Implications of brain-gut communication in the pathogenesis of psychiatric disorders indicate a possible role of suitably packaged/delivered probiotics as newer therapeutic options. In the present study probable role of per-oral administration of free Lactobacillus acidophilus (LAB) and LAB loaded alginate beads in attenuation of the symptoms associated with chronic fatigue syndrome (CFS) were evaluated.

METHODS

  Chronic fatigue syndrome following physical fatigue was induced in rats by forcing them to swim (forced swim test; FST) in water till exhaustion, after weighing them down with 10% their body weight, daily for 28 days. Immobility (I) and postswim fatigue time (PSF) were taken as suitable markers. Free LAB and LAB loaded floating beads (FBs) were administered, from 21 to 28 days.

KEY RESULTS

  Immobility and PSF were found to increase considerably in FST rats (665 ± 22 s and 196 ± 6 s) as compared with the naïve (32 ± 7 s and 22 ± 2 s) at 20 days, establishing severe fatigue like behavior. FST control group exhibited significant (P < 0.05) hypertrophy of spleen, hypotrophy of thymus, and increased oxido-nitrosative stress in brain and tumor necrosis factor-α (TNF-α) levels in serum. Treatment with LAB and LAB FBs significantly decreased I and PSF and attenuated (P < 0.05) oxido-nitrosative stress and TNF-α levels. Spleen and thymus were also restored to their original size in this group.

CONCLUSIONS & INFERENCES

  The findings suggest a valuable therapeutic role of LAB especially when incorporated into alginate beads for the treatment of CFS.

Curcumin ameliorates reserpine-induced pain-depression dyad: behavioural, biochemical, neurochemical and molecular evidences

An apparent clinical relationship between pain and depression has long been recognized. Depression and pain are often diagnosed in the same patients. The emerging concept for pain-depression pathogenesis is the dysfunction of biogenic amine-mediated pain-depression control and the possible involvement of nitrodative stress-induced neurogenic inflammation. The present study was designed to investigate the effect of curcumin on reserpine-induced pain-depression dyad in rats. Administration of reserpine (1mg/kg subcutaneous daily for three consecutive days) led to a significant decrease in nociceptive threshold as evident from reduced paw withdrawal threshold in Randall Sellitto and von-Frey hair test as well as significant increase in immobility time in forced swim test. This behavioural deficit was integrated with decrease in the biogenic amine (dopamine, norepinephrine and serotonin) levels along with increased substance P concentration, nitrodative stress, inflammatory cytokines, NF-κβ and caspase-3 levels in different brain regions (cortex and hippocampus) of the reserpinised rats. Curcumin (100, 200, 300mg/kg; ip) dose dependently ameliorated the behavioural deficits associated with pain and depression by restoring behavioural, biochemical, neurochemical and molecular alterations against reserpine-induced pain-depression dyad in rats.