Hemodynamic effects of synephrine treatment in portal hypertensive rats

Iranian traditional medicinal plants for management of chronic heart failure: A review

Chronic heart failure is a public health problem with a high prevalence worldwide and an important topic in clinical cardiology. Despite of advances in the drug treatment strategy for heart failure, the number of deaths from this condition continues to rise. It will be a renewed focus on preventing heart failure using proven and perhaps novel drugs. Management will also focus on comorbid conditions that may influence the progression of the disease. Traditional medicine has a potential to introduce different approaches for treatment of some disorders. We here reviewed top medicinal plants, according to traditional medicine to experimental studies, and their potency for the treatment of chronic heart failure based on the evidence of their functions.

2-Phenethylamines in Medicinal Chemistry: A Review

A concise review covering updated presence and role of 2-phenethylamines in medicinal chemistry is presented. Open-chain, flexible alicyclic amine derivatives of this motif are enumerated in key therapeutic targets, listing medicinal chemistry hits and appealing screening compounds. Latest reports in discovering new bioactive 2-phenethylamines by research groups are covered too.

p -Synephrine and its various pharmacological effects

There is a number of diseases for which, scientists are constantly looking for a promising new treatments. Isolation of novel substances with biological activity from plants gives hope for its use in treatment. In this review, we focused on the biological activity of p-synephrine (4-(2-aminoethyl)phenol) which was previously confirmed during both in vitro and in vivo tests. The main part of the review is dedicated to the anti-obesity activity of p-synephrine, as obesity is a disease of contemporary civilization. However, synephrine also possesses anti-diabetic, anti-inflammatory and antidepressant activity and it is confirmed to be a hypotensive agent in portal hypertension. The review also emphasize that, based on current knowledge, the use of p-synephrine appears to be exceedingly safe with only limited range of side effects. Therefore, it seems that this substance may be of great importance in the pharmacotherapy of many disease states and further research is necessary.

Therapeutic effects of medicinal plants on isoproterenol-induced heart failure in rats

AIMS

Natural products still serves as a hope for some illnesses which modern medicine fails to cure. Many people, either knowing their effects or not, are using these herbal products. Treatment of chronic heart failure (CHF) is yet a complicated clinical challenge and there is need to improve or make new therapeutic targets. Finding new agents for CHF is an important subject in cardiovascular drug research. In this study, we evaluated the effects of ten herbals on treatment of CHF on isoproterenol-induced model.

METHODS AND RESULTS

Ninety-six male Wistar rats (16 weeks old) were used in 12 groups. Transthoracic echocardiography was performed on the rats for confirmation of CHF model by decreasing ejection fraction. After 4 weeks' treatment, hearts were removed and blood samples were collected in tubes to measure plasma levels of laboratory findings. Our results showed that the mean of ejection fraction in model rats was 51.82 ± 3.49 percent and all of our used natural products could significantly increase the ejection fraction (P < 0.01). The most effective herbals in improving the ejection fraction were Allium sativum (30.69 %), Peganum harmala (26.08 %) and Apium graveolens (24.09 %). The best results in decreasing NT-ProBNP, was obtained from Allium sativum, Peganum harmala and Berberis vulgaris respectively. Our results showed that none of natural products had toxic effect on renal and liver tissues.

CONCLUSION

Our results showed that Allium sativum, Peganum harmala and Berberis vulgaris could significantly improve cardiac function by improvement of left ventricular remodeling, lowering hs-CRP and NT-ProBNP and echocardiographic indexes without liver or renal side effects.

Synephrine Hydrochloride Suppresses Esophageal Cancer Tumor Growth and Metastatic Potential through Inhibition of Galectin-3-AKT/ERK Signaling

A library consisting of 429 food-source compounds was used to screen the natural products with anticancer properties in esophageal squamous cell carcinoma (ESCC). We demonstrated for the first time that synephrine, an active compound isolated from leaves of citrus trees, markedly suppressed cell proliferation (inhibition rate with 20 μM synephrine at day 5:71.1 ± 5.8% and 75.7 ± 6.2% for KYSE30 and KYSE270, respectively) and colony formation (inhibition rate with 10 μM synephrine: 86.5 ± 5.9% and 82.3 ± 4.5% for KYSE30 and KYSE270, respectively), as well as migration (inhibition rate with 10 μM synephrine: 76.9 ± 4.4% and 62.2 ± 5.8% for KYSE30 and KYSE270, respectively) and invasion abilities (inhibition rate with 10 μM synephrine: 73.3 ± 7.5% and 75.3 ± 3.4% for KYSE30 and KYSE270, respectively) of ESCC cells in a dose-dependent manner, without significant toxic effect on normal esophageal epithelial cells. Mechanistically, quantitative proteomics and bioinformatics analyses were performed to explore the synephrine-regulated proteins. Western blot and qRT-PCR data indicated that synephrine may downregulate Galectin-3 to inactivate AKT and ERK pathways. In addition, we found that the sensitivity of ESCC to fluorouracil (5-FU) could be enhanced by synephrine. Furthermore, in vivo experiments showed that synephrine had significant antitumor effect on ESCC tumor xenografts in nude mice (inhibition rate with 20 mg/kg synephrine is 61.3 ± 20.5%) without observed side effects on the animals. Taken together, synephrine, a food-source natural product, may be a potential therapeutic strategy in ESCC.

A comparison of intra-operative blood loss and acid-base balance between vasopressor and inotrope strategy during living donor liver transplantation: a randomised, controlled study

Administration of vasopressors or inotropes during liver transplant surgery is almost universal, as this procedure is often accompanied by massive haemorrhage, acid-base imbalance, and cardiovascular instability. However, the actual agents that should be used and the choice between a vasopressor and an inotrope strategy are not clear from existing published evidence. In this prospective, randomised, controlled and single-blinded study, we compared the effects of a vasopressor strategy on intra-operative blood loss and acid-base status with those of an inotrope strategy during living donor liver transplantation. Seventy-six adult liver recipients with decompensated cirrhosis were randomly assigned to receive a continuous infusion of either phenylephrine at a dose of 0.3-0.4 μg.kg(-1).min(-1) or dopamine and/or dobutamine at 2-8 μg.kg(-1).min(-1) during surgery. Vascular resistance was higher over time in the phenylephrine group than in the dopamine/dobutamine group. Estimated blood loss was significantly lower in the phenylephrine group than in the dopamine/dobutamine group (mean (SD) 4.5 (1.8) l vs 6.1 (3.4) l, respectively, p=0.011). Patients in the phenylephrine group had lower lactate levels in the late pre-anhepatic and the early anhepatic phase and needed less bicarbonate administration than those in the dopamine/dobutamine group (median (IQR [range]) 40 (0-100 [0-160]) mEq vs 70 (40-163 [0-260]) mEq, respectively, p=0.018). Postoperative clinical outcomes and laboratory-measured hepatic and renal function did not differ between the groups. Increased vascular resistance and reduction of portal blood flow by intra-operative phenylephrine infusion is assumed to decrease the amount of intra-operative bleeding and thereby ameliorate the progression of lactic acidosis during liver transplant surgery.

Perioperative Assessment of Terlipressin Infusion during Living Donor Liver Transplantation

OBJECTIVE: To investigate the safety and efficacy of infusion of terlipressin during living donor liver transplantation (LDLT). METHODS: Patients undergoing LDLT with low systemic vascular resistance index (SVRI) and pulmonary vascular resistance index (PVRI) ( n = 41) were randomly allocated into control ( n = 20) and terlipressin groups ( n = 21). Terlipressin was infused at 1.0 – 4.0 μg/kg per h in the terlipressin group during surgery. Controls received generally accepted inotropic and vasopressor agents. RESULTS: Terlipressin infusion induced significantly higher SVRI and PVRI at 60 min after drug infusion, produced significantly greater hourly urine output during the anhepatic phase, and was related to significantly shorter stays in the postoperative intensive care unit (ICU) compared with control treatment (mean ± SD ICU stay 5.7 ± 1.5 versus 6.9 ± 1.5 days, respectively). Patients given a terlipressin infusion > 2.0 μg/kg per h during the preanhepatic phase had a median ICU stay of < 6 days (sensitivity 90.0%; specificity 89.0%). CONCLUSIONS: Terlipressin infusion improved low SVRI and PVRI during LDLT and may have contributed to better renal function and shorter ICU stays.

A review of the receptor-binding properties of p-synephrine as related to its pharmacological effects

Bitter orange (Citrus aurantium) extract and its primary protoalkaloid p-synephrine are used widely in weight loss/weight management and sports performance products. Because of structural similarities, the pharmacological effects of p-synephrine are widely assumed to be similar to those of ephedrine, m-synephrine (phenylephrine), and endogenous amine neurotransmitters as norepinephrine and epinephrine. However, small structural changes result in the receptor binding characteristics of these amines that are markedly different, providing a plausible explanation for the paucity of adverse effects associated with the wide-spread consumption of p-synephrine in the form of dietary supplements as well as in various Citrus foods and juices. This paper summarizes the adrenoreceptor binding characteristics of p-synephrine relative to m-synephrine, norepinephrine, and other amines as related to the observed pharmacological effects.

Anti-diabetic effect of standardized herbal formula PM021 consisting of Mori Folium and Aurantii Fructus on type II diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats

PM021, which consists of two herbal components, Mori Folium and Aurantii Fructus, is routinely used to treat diabetes in Korea. In this study, the anti-diabetic effect of PM021 on an animal model of developing type 2 diabetes of Otsuka Long-Evans Tokushima Fatty (OLETF) rats was investigated. Eight weeks of age male OLETF rats were treated daily with PM021 or vehicle for five months. Specifically, changes in body weight, blood glucose, urine volume, food intake and oral glucose tolerance were measured in rats for five months. The rats in this study were divided into four groups: a Long-Evans Tokushima Otsuka (LETO) rat group, which is a genetic control group for OLETF, that received no treatment; a PM021 treatment group of LETO rats; OLETF rats that received no treatment; and OLETF rats that received PM021 treatment. The results showed that PM021 significantly prevented increases in body weight, blood glucose, and urine and food intake that resulted from the induction of obesity and diabetes. PM021 also improved glucose tolerance in OLETO rats. However, PM021 had no effect on LETO rats, a control group of OLETF rats. Taken together, these findings indicate that PM021 has distinct anti-diabetic effects without any adverse effects or toxicities.

Hypertensive Urgency Associated With Xenadrine EFX Use

Several supplements and herbal products have been shown to increase catecholamines and subsequently mean arterial pressure and systemic vascular resistance. Since ephedra-containing products have been removed from the market, manufacturers of weight loss herbal supplements must produce ephedra-free formulations. Xenadrine EFX is an ephedra-free weight loss product containing a mixture of caffeine, guarana, and bitter orange (standardized to synephrine). Synephrine has been shown in animals and humans to increase systemic vascular resistance and mean arterial pressure. We present a case of a patient who took Xendarine EFX for 2 weeks prior to her presentation to an emergency department with headaches and hypertensive urgency (blood pressure [BP] 234/130 mm Hg). Her BP was controlled after discontinuation of Xenadrine and initiation a nitroprusside drip and oral clonidine. A Naranjo probability score of 6 indicates the adverse drug reaction was probable. Clinicians should be aware of potential cardiovascular changes in patients on Xenadrine EFX or other synephrine-containing products.

The safety of Citrus aurantium (bitter orange) and its primary protoalkaloid p-synephrine

Citrus aurantium (bitter orange) extract and its principal protoalkaloidal constituent p-synephrine are widely used in weight loss and weight management as well as in sports performance products. However, questions are raised frequently regarding the safety of these ingredients. The potential inherent dangers associated with the use of products containing C. aurantium extract are frequently touted, while conversely, millions of doses of dietary supplements have been consumed by possibly millions of individuals in recent years. Furthermore, millions of people consume on a daily basis various juices and food products from Citrus species that contain p-synephrine. This review summarizes current information regarding the safety of C. aurantium (bitter orange) extract and p-synephrine based on human, animal and in vitro assessments as well as receptor binding and mechanistic studies. The data indicate that based on current knowledge, the use of bitter orange extract and p-synephrine appears to be exceedingly safe with no serious adverse effects being directly attributable to these ingredients.

Anti-ischemic effect of Aurantii Fructus on contractile dysfunction of ischemic and reperfused rat heart

Aurantii Fructus (AF) is one of the most well-known traditional herbal medicines frequently used for the treatment of cardiovascular symptoms in Korea. The anti-ischemic effects of AF on ischemia-induced isolated rat heart were investigated through analyses of changes in perfusion pressure, aortic flow, coronary flow, and cardiac output. The subjects in this study were divided into two groups: an ischemia-induced group without any treatment, and an ischemia-induced group with AF treatment. There were no significant differences in perfusion pressure, aortic flow, coronary flow, and cardiac output between them before ischemia was induced. The supply of oxygen and buffer was stopped for 10 min to induce ischemia in isolated rat hearts, and AF was administered during ischemia induction. AF treatment significantly prevented decreases in perfusion pressure, aortic flow, coronary flow, and cardiac output under ischemic conditions (p < 0.01). These results suggest that AF has distinct anti-ischemic effects through recovery of contractile dysfunction in ischemic heart.

Ischemic stroke associated with use of an ephedra-free dietary supplement containing synephrine

In response to concerns regarding the safety of ephedra-containing dietary supplements, manufacturers have marketed "ephedra-free" products. Many of these contain synephrine, a sympathomimetic amine from the plant Citrus aurantium. Synephrine is structurally similar to ephedrine and has vasoconstrictor properties. We describe a 38-year-old patient with ischemic stroke associated with an ephedra-free dietary supplement containing synephrine and caffeine. The patient presented with memory loss and unsteady gait after taking 1 or 2 capsules per day of a dietary supplement (Stacker 2 Ephedra-Free) for 1 week. He had no notable medical history or major atherosclerotic risk factors and took no other medications. Physical examination showed a mildly ataxic gait and substantial Impairment of both concentration and memory. Computed tomography and magnetic resonance Imaging of the brain showed subacute infarctions in the left thalamus and left cerebellum in the distribution of the vertebrobasilar circulation. Other causes of ischemic stroke were evaluated, and findings were unremarkable; a vasospastic origin was considered most likely. The patient was discharged with nearly complete resolution of symptoms. Synephrine, a sympathomimetic amine related to ephedrine, may be associated with Ischemic stroke. Consumers and clinicians need to be Informed about the potential risks of ephedra-free products.

Citrus aurantium, an ingredient of dietary supplements marketed for weight loss: current status of clinical and basic research

Seville orange (Citrus aurantium) extracts are being marketed as a safe alternative to ephedra in herbal weight-loss products, but C. aurantium may also have the potential to cause adverse health effects. C. aurantium contains synephrine (oxedrine), which is structurally similar to epinephrine. Although no adverse events have been associated with ingestion of C. aurantium products thus far, synephrine increases blood pressure in humans and other species, and has the potential to increase cardiovascular events. Additionally, C. aurantium contains 6',7'-dihydroxybergamottin and bergapten, both of which inhibit cytochrome P450-3A, and would be expected to increase serum levels of many drugs. There is little evidence that products containing C. aurantium are an effective aid to weight loss. Synephrine has lipolytic effects in human fat cells only at high doses, and octopamine does not have lipolytic effects in human adipocytes.