Tesofensine, a novel antiobesity drug, silences GABAergic hypothalamic neurons.

Obesity is a major global health epidemic that has adverse effects on both the people affected as well as the cost to society. Several anti-obesity drugs that target GLP-1 receptors have recently come to the market. Here, we describe the effects of tesofensine, a novel anti-obesity drug that acts as a triple monoamine neurotransmitter reuptake inhibitor. Using various techniques, we investigated its effects on weight loss and underlying neuronal mechanisms in mice and rats. These include behavioral tasks, DeepLabCut videotaped analysis, electrophysiological ensemble recordings, optogenetic activation, and chemogenetic silencing of GABAergic neurons in the Lateral Hypothalamus (LH). We found that tesofensine induces a greater weight loss in obese rats than lean rats, while differentially modulating the neuronal ensembles and population activity in LH. In Vgat-ChR2 and Vgat-IRES-cre transgenic mice, we found for the first time that tesofensine inhibited a subset of LH GABAergic neurons, reducing their ability to promote feeding behavior, and chemogenetically silencing them enhanced tesofensine's food-suppressing effects. Unlike phentermine, a dopaminergic appetite suppressant, tesofensine causes few, if any, head-weaving stereotypy at therapeutic doses. Most importantly, we found that tesofensine prolonged the weight loss induced by 5-HTP, a serotonin precursor, and blocked the body weight rebound that often occurs after weight loss. Behavioral studies on rats with the tastant sucrose indicated that tesofensine's appetite suppressant effects are independent of taste aversion and do not directly affect the perception of sweetness or palatability of sucrose. In summary, our data provide new insights into the effects of tesofensine on weight loss and the underlying neuronal mechanisms, suggesting that tesofensine may be an effective treatment for obesity and that it may be a valuable adjunct to other appetite suppressants to prevent body weight rebound.

Efficacy and safety of oral magnesium supplementation in reducing febrile neutropenia episodes in children with solid tumors treated with cisplatin-based chemotherapy: randomized clinical trial.

PURPOSE: Hypomagnesemia has been associated with febrile neutropenia (FN) in pediatric patients receiving cisplatin-based chemotherapy (CDDPBC). The primary aim was to determine whether oral magnesium supplementation reduces FN episodes in pediatric patients with solid tumors treated with CDDPBC. METHOD: This randomized clinical trial, with open-label, single-center, parallel group and superiority design was conducted in Hospital Infantil de Mexico Federico Gomez at Mexico City. Children ≥ 9 years with solid tumors that were to receive a CDDPBC cycle were invited to participate. Each chemotherapy cycle with CDDPBC was randomly assigned to receive oral magnesium supplementation (250 mg/day) or not receive magnesium supplementation (control group). Efficacy was determined by relative risks (RR) with 95% confidence intervals (95% CI) as well as with numbers needed to treat (NNT). Active surveillance was conducted to assess safety in both groups. Analyses were carried out by intention to treat. ClinicalTrials.gov number NCT03449693. RESULTS: One hundred and one chemotherapy cycles with CDDPBC were analyzed (50 in the magnesium supplement arm and 51 in control group). Baseline clinical characteristics were similar comparing both groups. Oral magnesium supplementation reduces FN episodes compared to control group [RR 0.53, (95% CI 0.32-0.89), NNT = 4]. In the supplemented group, patients had fewer episodes of septic shock secondary to FN [RR 0.43, (95% CI 0.02-0.94), NNT = 6] and FN appeared on average 5 days later (p = 0.031). Hypomagnesemia episodes and adverse events were similar across both groups. CONCLUSION: Oral supplementation with magnesium reduces FN episodes neutropenia in pediatric patients with solid tumors treated with CDDPBC.

Pharmacological interaction of α-bisabolol and diclofenac on nociception, inflammation, and gastric integrity in rats.

Preclinical Research & Development The combination of nonsteroidal anti-inflammatory drugs (NSAIDs) with herbal products having analgesic and anti-inflammatory effects may increase their beneficial effects and limit their side effects. In this study, the effects of an interaction between α-bisabolol and the NSAID, diclofenac on nociception (formalin test), inflammation (paw inflammation produced by carrageenan) and gastric injury in rat was assessed. Diclofenac, α-bisabolol, or diclofenac-α-bisabolol combinations produced antinociceptive and anti-inflammatory effects in rat (p < .05). The systemic administration of diclofenac, but not α-bisabolol, produced gastric damage while the diclofenac-α-bisabolol combinations produced limited gastric damage. Effective dose (ED40 ) values were determined for each individual drug and analyzed isobolographically. The theoretical ED40 values for the antinociceptive (98.89 mg/kg) and the anti-inflammatory (41.2 mg/kg) effects differed from the experimental ED40 values (antinociception: 38.7 mg/kg and anti-inflammation: 13.4 mg/kg). We concluded that the interactions between diclofenac and α-bisabolol are synergistic. These data suggest that the diclofenac-α-bisabolol combinations can interact to produce minor gastric damage, thereby offering a safer therapeutic alternative for the clinical management of inflammation and/or inflammatory pain.

Synergistic Interaction of Matricaria Chamomilla Extract with Diclofenac and Indomethacin on Carrageenan-Induced Paw Inflammation in Rats.

Preclinical Research The coadministration of non-steroidal anti-inflammatory drugs (NSAIDs) with medicinal plant extracts may increase anti-inflammatory activity, thus permitting the use of lower NSAID doses and limiting the side effects. The aim of this study was to explore the interactions between an ethanolic extract of M. chamomilla extract (MCE) with two NSAIDs, diclofenac and indomethacin on carrageenan-induced paw inflammation and gastric injury in rats. Diclofenac, indomethacin and MCE, or combinations with MCE produced an anti-inflammatory effect. Effective dose (ED) values were estimated for the individual drugs, and isobolograms were constructed. The final experimental ED values were 483.7 mg/kg for diclofenac + MCE combination, and 212.6 mg/kg for indomethacin + MCE. These values were lower (p < 0.05) than the theoretical ED values (1186.9 mg/kg for diclofenac + MCE combination, and 1183.8 mg/kg for indomethacin + MCE). These data suggest that the interactions between NSAIDs and MCE that mediate the anti-inflammatory effects at the systemic level are synergistic and may have therapeutic advantages for the clinical treatment of inflammatory processes. Drug Dev Res 78 : 360-367, 2017. © 2017 Wiley Periodicals, Inc.

Evidence against the participation of a pharmacokinetic interaction in the protective effect of single-dose curcumin against gastrointestinal damage induced by indomethacin in rats.

OBJECTIVE: To determine the role of a pharmacokinetic interaction in the protective effect of curcumin against the gastric damage induced by indomethacin administration as such or as its prodrug acemetacin. METHODS: Wistar rats orally received single dose of indomethacin (30 mg/kg) with and without curcumin (30 mg/kg); gastric injury was evaluated by determining the total damaged area. Additional groups of rats received an oral single dose of indomethacin (30 mg/kg) or its prodrug acemetacin (34.86 mg/kg) in the presence or absence of curcumin (30 mg/kg). Indomethacin and acemetacin concentrations in plasma from blood draws were determined by high-performance liquid chromatography.Plasma concentration-against-time curves were constructed, and bioavailability parameters, maximal concentration (Cmax) and area under the curve to the last sampling time (AUC0-t) were estimated. RESULTS: Concomitant administration of indomethacin and curcumin resulted in a significantly reduced gastric damage compared to indomethacin alone. However, co-administration of curcumin did not produce any significant alteration in the bioavailability parameters of indomethacin and acemetacin after administration of either the active compound or the prodrug. CONCLUSION: Curcumin exhibits a protective effect against indomethacin-induced gastric damage, but does not produce a reduction of the bioavailability of this nonsteroidal anti-inflammatory drug, indomethacin. Data thus suggest that a pharmacokinetic mechanism of action is not involved in curcumin gastroprotection.

Isolation, identification and molecular docking as cyclooxygenase (COX) inhibitors of the main constituents of Matricaria chamomilla L. extract and its synergistic interaction with diclofenac on nociception and gastric damage in rats.

Chamomile (Matricaria chamomilla L., Asteraceae) is a medicinal plant widely used as remedy for pain and gastric disorders. The association of non-steroidal anti-inflammatory drugs (NSAIDs) with medicinal plant extracts may increase its antinociceptive activity, permit the use of lower doses and limit side effects. The aim was to isolate and identify the main chemical constituents of Matricaria chamomilla ethanolic extract (MCE) as well as to explore their activity as cyclooxygenase (COX) inhibitors in silico; besides, to examine the interaction between MCE and diclofenac on nociception in the formalin test by isobolographic analysis, and to determine the level of gastric injury in rats. Three terpenoids, α-bisabolol, bisabolol oxide A, and guaiazulene, were isolated and identified by (1)H NMR. Docking simulation predicted COX inhibitory activity for those terpenoids. Diclofenac, MCE, or their combinations produced an antinociceptive effect. The sole administration of diclofenac and the highest combined dose diclofenac-MCE produced significant a gastric damage, but that effect was not seen with MCE alone. An isobologram was constructed and the derived theoretical ED35 for the antinociceptive effect was significantly different from the experimental ED35; hence, the interaction between diclofenac and MCE that mediates the antinociceptive effect is synergist. The MCE contains three major terpenoids with plausible COX inhibitory activity in silico, but α-bisabolol showed the highest affinity. Data suggest that the diclofenac-MCE combination can interact at the systemic level in a synergic manner and may have therapeutic advantages for the clinical treatment of inflammatory pain.

Cisplatin Nephrotoxicity and Longitudinal Growth in Children With Solid Tumors: A Retrospective Cohort Study.

Cisplatin, a major antineoplastic drug used in the treatment of solid tumors, is a known nephrotoxin. This retrospective cohort study evaluated the prevalence and severity of cisplatin nephrotoxicity in 54 children and its impact on height and weight.We recorded the weight, height, serum creatinine, and electrolytes in each cisplatin cycle and after 12 months of treatment. Nephrotoxicity was graded as follows: normal renal function (Grade 0); asymptomatic electrolyte disorders, including an increase in serum creatinine, up to 1.5 times baseline value (Grade 1); need for electrolyte supplementation <3 months and/or increase in serum creatinine 1.5 to 1.9 times from baseline (Grade 2); increase in serum creatinine 2 to 2.9 times from baseline or need for electrolyte supplementation for more than 3 months after treatment completion (Grade 3); and increase in serum creatinine ≥3 times from baseline or renal replacement therapy (Grade 4).Nephrotoxicity was observed in 41 subjects (75.9%). Grade 1 nephrotoxicity was observed in 18 patients (33.3%), Grade 2 in 5 patients (9.2%), and Grade 3 in 18 patients (33.3%). None had Grade 4 nephrotoxicity. Nephrotoxicity patients were younger and received higher cisplatin dose, they also had impairment in longitudinal growth manifested as statistically significant worsening on the height Z Score at 12 months after treatment. We used a multiple logistic regression model using the delta of height Z Score (baseline-12 months) as dependent variable in order to adjust for the main confounder variables such as: germ cell tumor, cisplatin total dose, serum magnesium levels at 12 months, gender, and nephrotoxicity grade. Patients with nephrotoxicity Grade 1 where at higher risk of not growing (OR 5.1, 95% CI 1.07-24.3, P=0.04). The cisplatin total dose had a significant negative relationship with magnesium levels at 12 months (Spearman r=-0.527, P=<0.001).

Synergistic effect of the interaction between curcumin and diclofenac on the formalin test in rats.

The association of non-steroidal anti-inflammatory drugs with certain plant extracts can increase antinociceptive activity, permitting the use of lower doses and thus limiting side effects. Therefore, the aim objective of the current study was to examine the effects of curcumin on the nociception and pharmacokinetics of diclofenac in rats. Antinociception was assessed using the formalin test. Diluted formalin was injected subcutaneously into the dorsal surface of the right hind paw. Nociceptive behavior was quantified as the number of flinches of the injected paw during 60 min after injection, and a reduction in formalin-induced flinching was interpreted as an antinociceptive response. Rats were treated with oral diclofenac (1-31 mg/kg), curcumin (3.1-100 mg/kg) or the diclofenac-curcumin combination (2.4-38.4 mg/kg). To determine the possibility of a pharmacokinetic interaction, the oral bioavailability of diclofenac (10 mg/kg) was studied in presence and the absence of curcumin (31 mg/kg). Diclofenac, curcumin, or diclofenac-curcumin combination produced an antinociceptive effect on the formalin test. ED30 values were estimated for the individual drugs, and an isobologram was constructed. The derived theoretical ED30 for the antinociceptive effect (19.2 mg/kg) was significantly different from the observed experimental ED30 value (9.8 mg/kg); hence, the interaction between diclofenac and curcumin that mediates the antinociceptive effect was synergistic. Notwithstanding, the interaction does not appear to involve pharmacokinetic mechanisms, as oral curcumin failed to produce any significant alteration in oral diclofenac bioavailability. Data suggest that the diclofenac-curcumin combination can interact at the systemic level and may have therapeutic advantages for the clinical treatment of inflammatory pain.

The combination of naproxen and citral reduces nociception and gastric damage in rats.

It has been shown that the association of non-steroidal anti-inflammatory drugs with plant extracts can increase their antinociceptive activity, allowing the use of lower doses and, thus, limiting side effects. Therefore, the aim of this study was to examine the effects of the interaction between naproxen and citral on nociception and gastric injury in rats. Naproxen, citral, or combinations of naproxen and citral produced an antinociceptive effect. The administration of naproxen produced significant gastric damage, but this effect was not obtained with either citral or the naproxen-citral combination. The ED(50) value was estimated for the individual drugs and an isobologram was constructed. The derived theoretical ED(50) for the antinociceptive effect (423.8 mg/kg) was not significantly different from the observed experimental value (359.0 mg/kg); hence, the interaction between naproxen and citral mediating the antinociceptive effect is additive. These data suggest that the naproxen-citral combination interacts at the systemic level, produces minor gastric damage, and potentially has therapeutic advantages for the clinical treatment of inflammatory pain.

Synergistic effect of the interaction between naproxen and citral on inflammation in rats.

The combination of non-steroidal anti-inflammatory drugs with herbs having analgesic effects can increase their antinociceptive activity and limit their side effects. The aim of the present study was to examine the effects on inflammation and gastric injury in rats resulting from the interaction between naproxen and citral. Naproxen, citral, or fixed-dose naproxen-citral combinations were administered orally and their anti-inflammation (carrageenan-induced paw edema) and gastric damage were assessed in rats. The pharmacological interaction type was evaluated by the isobolographic analysis. Naproxen, citral, or combinations of naproxen and citral produced anti-inflammatory effects. The sole administration of naproxen produced significant gastric damage, but this effect was not obtained with either citral or combinations. ED(30) values were estimated for the individual drugs, and isobolograms were constructed. The derived theoretical ED(30) for the anti-inflammatory effect was 504.4 mg/kg; this was significantly higher than the observed experimental value (190.6 mg/kg). These results indicate that a synergistic interaction underlies the anti-inflammatory effect. The data suggests that the naproxen-citral combination can interact and to produce minor gastric damage and may have therapeutic advantages for the clinical treatment of inflammation.

Antihyperalgesia induced by Heliopsis longipes extract.

Heliopsis longipes is an herbaceous plant found in Mexico. Heliopsis longipes is traditionally used for its analgesic and anesthetic properties. Plant extracts may represent a therapeutic advantage for the clinical treatment of pain. Therefore, the main objective of this study was to determine the possible antihyperalgesic effect produced by the Heliopsis longipes ethanolic extract (HLEE) in the Hargreaves model of thermal hyperalgesia in the mouse. HLEE was administrated systemically to mice and the antihyperalgesic effect was evaluated using the thermal hyperalgesia test. Oral Administration of HLEE produced a dose-dependent antihyperalgesic effect. Previously, it was reported that Heliopsis longipes extract was able to release GABA in mice temporal cortex slices. Therefore, it is likely that the antihyperalgesic effect observed in our study could result from GABA liberation and its inhibition of excessive excitation of nociceptive circuits in the thalamus and cortex evoked by tissue injury. Our results suggest that HLEE may represent a therapeutic advantage for the clinical treatment of inflammatory pain.

L-arginine reverses alterations in drug disposition induced by spinal cord injury by increasing hepatic blood flow.

High hepatic extraction drugs--such as phenacetin, methylprednisolone, and cyclosporine--exhibit an increased bioavailability after acute spinal cord injury (SCI) due to an impaired clearance. For these drugs, metabolic clearance depends on hepatic blood flow. Thus, it is possible that pharmacokinetic alterations can be reversed by increasing liver perfusion. Therefore, we evaluated the effect of L-arginine, a nitric oxide precursor, on the pharmacokinetics of a prototype drug with high hepatic extraction, and on hepatic microvascular blood flow (MVBF) after acute SCI. Pharmacokinetics of i.v. phenacetin was studied in rats 24 h after a severe T-5 spinal cord contusion; animals being pretreated with L-arginine 100 mg/kg i.v. or vehicle. MVBF was assessed under similar experimental conditions using laser Doppler flowmetry. SCI significantly altered phenacetin pharmacokinetics. Clearance was significantly reduced, resulting in a prolonged half-life and an increase in bioavailability, while volume of distribution was decreased. Pharmacokinetic alterations were reversed when injured rats were pretreated with L -arginine. It was also observed that L-arginine significantly increased hepatic MVBF in injured rats, notwithstanding it exhibited a limited effect on sham-injured animals. Our data hence suggest that L-arginine is able to reverse SCI-induced alterations in phenacetin pharmacokinetics due to an impaired hepatic MVBF, likely by increased nitric oxide synthesis leading to vasodilation. Further studies are warranted to examine the potential usefulness of nitric oxide supplementation in a clinical setting.

Gastroprotection and effect of the simultaneous administration of Cuachalalate (Amphipterygium adstringens) on the pharmacokinetics and anti-inflammatory activity of diclofenac in rats.

This work aimed to study the effect of Cuachalalate methanol extract (CME) on the anti-inflammatory activity and pharmacokinetics of diclofenac sodium, a frequently prescribed non-steroidal anti-inflammatory drug (NSAID). The gastroprotective effect of CME on the gastric injury induced by diclofenac was studied in rats. CME showed a gastroprotective effect of 15.7% at 1 mg kg(-1) and 72.5% at dose of 300 mg kg(-1). Omeprazole, used as anti-ulcer reference drug, showed gastroprotective effects of 50-89.7% at doses tested (1-30 mg kg(-1)). The value of the 50% effective dose for the anti-inflammatory effect of diclofenac sodium (ED50 = 1.14 +/- 0.23 mg kg(-1)) using carrageenan-induced rat paw oedema model, was not modified by the concomitant administration of 30 or 100 mg kg(-1) of CME. The effect of CME (30, 100 and 300 mg kg(-1), p.o.) on the pharmacokinetics of diclofenac sodium was studied. It was observed that the simultaneous administration of diclofenac sodium and 300 mg kg(-1) of CME decreased significantly the values of Cmax (7.08 +/- 1.42 microg mL(-1)) and AUC (12.67 +/- 2.97 microg h mL(-1)), but not the value of tmax (0.13 (0.1-0.25)h) obtained with the administration of diclofenac alone. The simultaneous administration of 30 or 100 mg kg(-1) of CME did not modify the pharmacokinetic parameters of diclofenac. The experimental findings in rats suggest that CME at doses lower than 100 mg kg(-1) protects the gastric mucosa from the damage induced by diclofenac sodium without altering either the anti-inflammatory activity or the pharmacokinetics of this NSAID.

Nifedipina: farmacocinética y adecuado uso terapéutico / Nifedipine: pharmacokinetics and adequeate therapeutic use

Se presenta una visión global de diversos aspectos de la farmacodinamia, farmacocinética, consideraciones especiales, indicaciones terapéuticas y efectos adversos de la nifedipina y su implicación en población mexicana. Se revisa la utilidad real de la nifedipina por vía sublingual en la urgencia ipertensiva, en el manejo de la hipetensión arterial y su uso en México. Asimismo, se valora el mito de su riesgo en los pacientes a quiene se les administra nifedipina y se explica la evidencia de que este riesgo solo se presenta con la formulación de liberación rápida. Con base en esta revisión, se describen algunas conclusiones útiles para el médico que prescribe nifedipina. Se recomienda evitar la nifedipina de acción corta (cápsula) por la ruta oral en el tratamiento de la hipertensión arterial. Igualmente debe evitarse el uso de las cápsulas con nifedipina por vía sublingual en el manejo de la urgencia hipertensiva, ya que esta presentación es inadecuada para la absorción sublingual. Por otro lado, el uso de la nifedipina de acción prolongada se puede considerar de primera elección en el manejo de la hipertensión arterial