Effects of fenugreek, garden cress, and black seed on theophylline pharmacokinetics in beagle dogs

Changes in Pharmacokinetics and Pharmacodynamics of Losartan in Experimental Diseased Rats Treated with Curcuma longa and Lepidium sativum

The current study investigated “pharmacodynamics and pharmacokinetics interactions” of losartan with Curcuma longa (CUR) and Lepidium sativum (LS) in hypertensive rats. Hypertension was induced by oral administration of L-NAME (40 mg/kg) for two weeks. Oral administration of CUR or LS shows some substantial antihypertensive activity. The systolic blood pressure (SBP) of hypertensive rats was decreased by 7.04% and 8.78% 12 h after treatment with CUR and LS, respectively, as compared to rats treated with L-NAME alone. LS and CUR display the ability to potentiate the blood pressure-lowering effects of losartan in hypertensive rats. A greater decrease in SBP, by 11.66% and 13.74%, was observed in hypertensive rats treated with CUR + losartan and LS + losartan, respectively. Further, both the investigated herbs, CUR and LS, caused an increase in plasma concentrations of losartan in hypertensive rats. The AUC0-t, AUC0-inf and AUMC0-inf of losartan were increased by 1.25-fold, 1.28-fold and 1.09-fold in hypertensive rats treated with CUR + losartan. A significant (p < 0.05) increase in AUC0-t (2.41-fold), AUC0-inf (3.86-fold) and AUMC0-inf (8.35-fold) of losartan was observed in hypertensive rats treated with LS + losartan. The present study affirms that interactions between CUR or LS with losartan alter both “pharmacokinetics and pharmacodynamics” of the drug. Concurrent administration of losartan with either CUR or LS would require dose adjustment and intermittent blood pressure monitoring for clinical use in hypertensive patients. Additional investigation is necessary to determine the importance of these interactions in humans and to elucidate the mechanisms of action behind these interactions.

Effects of garden cress, fenugreek and black seed on the pharmacodynamics of metoprolol: an herb-drug interaction study in rats with hypertension

CONTEXT

Garden cress (GC), fenugreek (FG), and black seed (BS) are traditional herbal medicine for managing hypertension.

OBJECTIVE

The effects of the three herbs on the pharmacodynamics of metoprolol tartrate (MT) in hypertensive rats were investigated.

MATERIALS AND METHODS

Wistar rats were divided in five groups (n = 6). Group I served as normal control group and Group II (hypertensive control group) had rats treated orally with N-nitro L-arginine methyl ester (L-NAME, 40 mg/kg/day) only. Groups III, IV, and V rats were orally treated with L-NAME (40 mg/kg/day) + GC (300 mg/kg, once daily), L-NAME (40 mg/kg/day) + FG (300 mg/kg, once daily) and L-NAME (40 mg/kg/day) + BS (300 mg/kg, once daily), respectively, for 2 weeks, and on the 14th day, blood pressure and heart rate were recorded using a tail-cuff blood pressure-measuring system. On the 16th day, a single dose of MT (10 mg/kg) was orally administered, and the rats' blood pressure and heart rate were recorded.

RESULTS

GC, FG, and BS decreased systolic blood pressure (SBP) by 8.7%, 8.5%, and 8.7%, respectively, in hypertensive rats. A greater decrease in SBP by 14.5%, 14.8%, and 16.1% was observed when hypertensive rats were treated with L-NAME + GC + MT, L-NAME + FG + MT, and L-NAME + BS + MT, respectively. Similarly, hypertensive rats treated with the combination of herbs and MT had significantly lower diastolic blood pressure (DBP) than those treated with herbs alone and those treated with L-NAME alone.

CONCLUSIONS

The combination of investigated herbs and MT had a beneficial effect on hypertension. However, the concurrent administration of drugs, particularly those predominantly cleared through CYP450 2D6-catalyzed metabolism, with the three investigated herbs should be considered with caution.

Black Cumin (Nigella sativa L.): A Comprehensive Review on Phytochemistry, Health Benefits, Molecular Pharmacology, and Safety

Mounting evidence support the potential benefits of functional foods or nutraceuticals for human health and diseases. Black cumin (Nigella sativa L.), a highly valued nutraceutical herb with a wide array of health benefits, has attracted growing interest from health-conscious individuals, the scientific community, and pharmaceutical industries. The pleiotropic pharmacological effects of black cumin, and its main bioactive component thymoquinone (TQ), have been manifested by their ability to attenuate oxidative stress and inflammation, and to promote immunity, cell survival, and energy metabolism, which underlie diverse health benefits, including protection against metabolic, cardiovascular, digestive, hepatic, renal, respiratory, reproductive, and neurological disorders, cancer, and so on. Furthermore, black cumin acts as an antidote, mitigating various toxicities and drug-induced side effects. Despite significant advances in pharmacological benefits, this miracle herb and its active components are still far from their clinical application. This review begins with highlighting the research trends in black cumin and revisiting phytochemical profiles. Subsequently, pharmacological attributes and health benefits of black cumin and TQ are critically reviewed. We overview molecular pharmacology to gain insight into the underlying mechanism of health benefits. Issues related to pharmacokinetic herb-drug interactions, drug delivery, and safety are also addressed. Identifying knowledge gaps, our current effort will direct future research to advance potential applications of black cumin and TQ in health and diseases.

Effect of Nigella sativa and Fenugreek on the Pharmacokinetics and Pharmacodynamics of Amlodipine in Hypertensive Rats

BACKGROUND

The present article is related to in-vitro and in-vivo herb-drug interaction studies.

OBJECTIVES

This study aimed to investigate the effect of Nigella sativa and fenugreek on the pharmacodynamics and pharmacokinetics of amlodipine.

METHOD

Hypertensive rats of group-I were treated with amlodipine and rats of group-II and III were treated with N. sativa, and N. sativa + amlodipine and fenugreek, and fenugreek + amlodipine, respectively. Systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean blood pressure (MBP) of group-I, II and III rats were measured by the "tail-cuff system".

RESULTS

N. sativa, as well as fenugreek, reduced the SBP, DBP and MBP. Simultaneously, administration of fenugreek + amlodipine or N. sativa + amlodipine showed better control of BP. Individually, fenugreek, as well as N. sativa, showed a surprising reduction in the heart rate. There was no remarkable effect of any of these two herbs on Cmax, AUC0-t, Kel, and terminal elimination half-life of amlodipine, but fenugreek altered the Tmax of amlodipine significantly, from 2 ± 1.2h in control to 7.2 ± 1.7h in fenugreek treated group, probably by delaying the absorption.

CONCLUSION

Results of pharmacodynamics and pharmacokinetics studies suggested that simultaneous administration of fenugreek or N. sativa with amlodipine improved the pharmacological response of amlodipine in hypertensive rats, though there was no remarkable change in pharmacokinetic parameters (Cmax, Kel, elimination t1/2, and AUC0-t).

PharmActa: Empowering Patients to Avoid Clinical Significant Drug⁻Herb Interactions

Herbal medicinal products (HMPs) are the subject of increasing interest regarding their benefits for health. However, a serious concern is the potential appearance of clinically significant drug⁻herb interactions in patients. This work provides an overview of drug⁻herb interactions and an evaluation of their clinical significance. We discuss how personalized health services and mobile health applications can utilize tools that provide essential information to patients to avoid drug⁻HMP interactions. There is a specific mention to PharmActa, a dedicated mobile app for personalized pharmaceutical care with information regarding drug⁻HMPs interactions. Several studies over the years have shown that for some HMPs, the potential to present clinically significant interactions is evident, especially for many of the top selling HMPs. Towards that, PharmActa presents how we can improve the way that information regarding potential drug⁻herb interactions can be disseminated to the public. The utilization of technologies focusing on medical information and context awareness introduce a new era in healthcare. The exploitation of eHealth tools and pervasive mobile monitoring technologies in the case of HMPs will allow the citizens to be informed and avoid potential drug⁻HMPs interactions enhancing the effectiveness and ensuring safety for HMPs.

Herbal Bioenhancers in Veterinary Phytomedicine

Herbal bioenhancers are active phytomolecules that increase the bioavailability, bioefficacy and biological activity of various drugs when coadministered at low concentrations. These valuable compounds reduce the dose, increase the treatment rate, decrease the treatment duration, drug resistance or related adverse reactions which have economical implications in livestock and pet medicine. Eventhough the concept of herbal bioenhancers are known for years through Ayurvedic medicine, the underlying mechanisms remains unclear. The main mechanisms involved are related to drug absorption (effect on solubility, drug efflux and transport proteins, increased permeability in gastrointestinal system) and drug metabolism (inhibition/induction of drug metabolysing enzymes, thermogenic effect). Due to species specific differences in these mechanisms, corresponding data on human and laboratory animal could not be attributed. As multidrug resistance is a major treat to both human and animal health, within "One Health" concept, efficient therapeutical strategies are encouraged by authorities, where focus on herbal supplements as a vast unexploited field remains to be researched within "Bioenhancement Concept." This review brings insight to mechanims involved in bioenhancing effect, examples of herbal extracts and phytoactive compounds and their potential in the veterinary medicine including different classes of drugs such as antibiotics, anticancerous, antiviral, and antituberculosis.

Natural Health Products and Diabetes: A Practical Review

The prevalence of natural health product (NHP) use in Canada is extensive. Patients with chronic diseases, including diabetes, use NHPs at a higher rate than the general population. Many NHPs exert hypoglycemic effects, among other effects relevant to diabetes management. To provide a practical, clinical review of NHPs with such effects targeted to pharmacists, a literature search was performed to collect data on the efficacy and safety profiles of 10 commonly used NHPs that exert antidiabetic properties. The following NHPs are included in this clinical review: alpha-lipoic acid, chromium, magnesium, bitter melon, cinnamon, fenugreek, gymnema, milk thistle, Reishi mushroom and white mulberry. Given the potential of NHPs to additively cause hypoglycemia when used concurrently with conventional medications, pharmacists should be up to date with current evidence around NHPs that may affect diabetes care to prevent adverse reactions and interactions. In addition, effective and respectful communication with patients around NHP use and collaboration with various health-care providers are essential in the patient care process.

Pharmacokinetic interaction of Acacia catechu with CYP1A substrate theophylline in rabbits

OBJECTIVE

To investigate the effect of black catechu (BC) on the pharmacokinetics of theophylline (CYP1A2 substrate, with narrow therapeutic index) in rabbits.

METHODS

In the present investigation the effect of BC on the pharmacokinetics of theophylline, a CYP1A2 substrate was determined. In the study, BC (264 mg/kg, p. o.) or saline (control group) was given to rabbits for 7 consecutive days and on the 8th day theophylline (16 mg/kg) was administered orally one hour after BC or saline treatment. Blood samples were withdrawn at different time intervals (0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 24 and 36 h) from the marginal ear vein.

RESULTS

The pretreatment of rabbits with BC resulted in a significant increase in maximum blood concentration, time of peak concentration and area under the concentration time profile curve until last observation which was about 41.32%, 35.71% and 15.03%, respectively. While decreases in clearance, volume of distribution, and half-life were observed. It is suggested that BC pretreatment decreases the CYP1A metabolic activity leading to increase in bioavailability and decrease in oral clearance of theophylline, which may be due to inhibition of CYP1A.

CONCLUSION

BC can significantly alter theophylline pharmacokinetics in vivo possibly due to inhibition of CYP1A and P-glycoprotein activity. Based on these results, precaution should be exercised when administering BC with CYP1A substrate.