Adapted Technological Platform for Screening and Identifying Compounds Capable of In vivo Spinal Network-mediated Reflex Ejaculation in Non-anesthetized, Chronic Paraplegic Mice: Evidence of Clonidine-elicited Seminal Emission.

Several drugs have been shown to facilitate locomotor rhythmogenesis and treadmill training after Spinal Cord Injury (SCI). Clonidine, an alpha-adrenoceptor agonist, is of particular interest given its well-known effects on facilitation of reflex-induced spinal stepping in acute or chronic complete low-thoracic spinal cord-transected (Tx) cats. Since locomotion and ejaculation are controlled by neuronal networks located in the same area of the spinal cord (i.e., upper- to mid-lumbar segments), we hypothesized that clonidine may have comparable effects on reflex ejaculation in low-thoracic Tx animals. To achieve that, the main aim was to adapt a technological platform developed initially for in vivo testing of pro-locomotor compounds in order to establish and validate an approach for assessing both behaviourally and quantitatively, drug-induced reflex ejaculation ex copula in an animal model of SCI. At 6 or 7 days post-Tx, male mice received a single injection of clonidine (0.005-2.5 mg/kg, i.p.). At doses ranging between 0.1 and 2.5 mg/kg, clonidine acutely induced, in 88% of cases (35/40 mice), seminal emissions as fluids or plugs (in-urethra) with no erection nor expulsion. Given that clonidine is a partial alpha-2 agonist, the results suggest that alpha-2 adrenoceptor activation is associated with seminal emission in non-copulating and non-stimulated (e.g., manually or electrically) chronic paraplegic mice. To our knowledge, this is the first report of alpha-2-mediated, clonidine-induced seminal emission.

A Novel Approach for Innovative Pharmaceutical, Nutraceutical and Biocosmeceutical Products: Different Types of Combination Products and Co-activation of Natural Synergistically Acting Target-Receptors (CanSATs).

Traditionally, the main model of the pharmaceutical industry for developing new drugs has been based on monotherapies, new molecular entities (NMEs), and their underlying one-target-one-disease dogma. It is no surprise that closely related fields such as the cosmeceutical and nutraceutical areas, largely inspired by Big Pharma, have also mainly used that model. However, compelling evidence suggests that the time has come for these sectors of R&D activities to further explore more efficient, cost-effective and reliable approaches for innovative products. Among a few approaches proposed in recent years, there is one that is of particular interest – the ‘combination drug’ often referred to as the fixed-dose combination (FDC) products approach. It has been generally defined as two or more active ingredients that are combined in a single dosage form for either new effects or superior synergistic-like efficacy with less adverse effects. Both the World Health Organization (WHO) and the U.S. Food and Drug Administration (FDA) have recognized the great potential of FDCs for the future of innovation in those sectors. In fact, the development of FDCs has recently received substantial support for commercialization of new products – that is between three and five years of additional protection and exclusivity. Next-generation FDCs have already been identified. Indeed, FDCs that may be referred to as ‘variable-dose combinations’ (VDCs) products and, more specifically, ‘Co-Activation of Natural Synergistically-Acting Target-Receptors’ (CanSATs) products when applied to natural products if synergistic-like actions are found among active ingredients. Although VDCs and CanSATs have emerged mainly from the nutraceutical and cosmeceutical sectors, these approaches may perhaps also promote the development of promising new pharmaceutical products.

Quantitative Behavioral Method for Assessing Pharmacologically-Induced Episodes of Micturition in an Animal Model of Urinary Retention and Detrusor-Sphincter Dyssynergia.

No cure or acceptable treatment exists against bladder problems and urinary retention in spinal cord-injured (SCI) patients. Although some non-central nervous system (CNS)-acting drugs exist, as symptomatic treatment, most have been associated with significant side effects and deleterious complications. To ease basic research aimed at identifying new drug candidates against bladder control problems, we develop a standardized approach and corresponding assays for assessing quantitatively acute recovery of bladder expression and episodic urination elicited by CNS-acting compounds in paraplegic animals. Following a period of acclimation, a single systemic (s.c.) injection of vehicle (sterile water) was performed in intact animals or in early chronic (7-10 days post-surgery) thoracically (Th9/10)-transected (Tx) mice. Observations were immediately conducted during 30 minutes using a transparent circular Plexiglas arena where timing (post-injection), frequency (number of episodes post-injection), incidences and total volumes (mg) of expulsed urine were assessed. In clear contrast, administration of quipazine, a 5-HT2/3 receptor agonist was shown here to elicit increased urine volume expressed within 30 min post-administration in Tx mice. Using this simple, straightforward and reliable method, it will become possible to conduct large scale drug screening experiments aimed at identifying potent and safe centrally acting-drugs (e.g., upon the Sacral/Spinal Micturition Center) for potent ‘on-demand’ facilitation of urination and voiding in patients with SCI.

Proof-of-Concept of Acute Drug-Elicited Defecatory Behaviors in Spinal Cord-Transected Animals: A Model for Identifying Centrally-Acting Prokinetic Agents.

No cure and no safe or acceptable treatment exist yet against bowel problems and chronic constipation in spinal cord-injured (SCI) patients. Although some non-central nervous system (CNS)-acting drugs have already been identified and used clinically as symptomatic treatment, most have been associated with significant side effects and deleterious complications. To ease basic research aimed at identifying new drug candidates against bowel control problems, we developed a standardized approach and corresponding assays for quantitatively measuring prokinetic and acute defecatory effects in paraplegic animals. Following a period of acclimation, a single subcutaneous injection of 0.5 ml of vehicle (sterile water) was performed in normal animals or in early chronic (> 7 days post-surgery) low-thoracically (Th9/10)-transected (Tx) mice. A 30 minute-period of observation of freely moving animals using a transparent Plexiglas arena was used to subsequently measure timing (latency of each episode), amounts (fecal pellets in mg) and frequency (number of episodes/30 min). Residual activity levels, clearly determined in control animals, were used as baseline level to determine statistically greater effects induced by compounds of potential interest. Tests with SR57227 (5-HT3 receptor agonist) and quipazine (5-HT2/3 receptor agonist) revealed that only quipazine acutely elicited significantly greater amounts of fecal pellets in Tx mice. Using this straightforward and reliable method, future drug screening experiments that may yield the identification and development of new potent and safe centrally acting-drug treatments (e.g., upon the Lumbosacral Defecation Center) for potent ‘on-demand’ facilitation or induction of reflex bowel control and acute episodes of defecation in patients with SCI.