Effects of matcha green tea on the pharmacokinetics of nadolol in rats

by Eslam T. Mashaqbeh, Tamam El-Elimat, Osama Y. Alshogran, Iyad Hamzeh, Zahraa M. Obeidat, Ahmed H. Al Sharie, Feras El Hajji

The concurrent use of herbal dietary supplements with prescription medications raises safety concerns due to the potential for clinically significant interactions. Matcha, a shade-grown green tea consumed as an ultra-fine powder, is rich in catechins that may inhibit the transport of P-glycoprotein (P-gp) substrates such as nadolol. This study investigated the effects of administering single and multiple doses of matcha on the pharmacokinetics of nadolol in an in vivo animal model. Male Sprague-Dawley rats (n = 32) were randomly assigned to four groups. Group 1 (negative control) was administered normal saline followed by a single oral dose of nadolol (10 mg/kg). Group 2 (matcha single-dose) was administered a single dose of matcha (250 mg/kg) whisked in normal saline, followed by nadolol (10 mg/kg) after 30 min. Group 3 (positive control) received itraconazole (50 mg/kg), followed by nadolol (10 mg/kg) after 30 min. Group 4 (matcha multiple-dose) received matcha (250 mg/kg daily for 21 days) before administering nadolol (10 mg/kg) on day 21. Blood samples were collected at 0, 0.33, 0.66, 1, 1.5, 2, 3, 4, 5, 8 and 24 h. Nadolol concentrations in plasma were measured by a validated high-performance liquid chromatography with fluorescence detection (HPLC-FL) method. Pharmacokinetic parameters were estimated using the PK solver add-in for Microsoft Excel. To ensure quality control, caffeine, a key marker compound of matcha green tea, was quantified using HPLC with ultraviolet detection (HPLC-UV). A single oral dosage of matcha (250 mg/kg) had no statistically significant effects on the pharmacokinetics of nadolol compared to the control group (p > .05). Although the multiple-dose matcha group showed an increase in C_max (~45%), AUC_0-t (~18%), and AUC_0-∞ (~22%) for nadolol compared to the control group, these differences were not statistically significant (p > .05). In contrast, the t½ (h) of nadolol increased significantly from 4.0 ± 1.6 in the control group to 7.7 ± 4.2 (p = .039) in the matcha multiple-dose group. Itraconazole co-administration significantly increased systemic exposure (AUC) of nadolol (p = .009), confirming the validity of the animal model. Caffeine, a key marker compound in matcha tea, was quantified at 4.18 ± 0.44% w/w of dry matcha tea powder, equivalent to 41.8 ± 4.4 mg/g. This is the first study to explore the potential pharmacokinetic interaction between matcha tea and nadolol. Single and multiple oral doses of matcha green tea had negligible effects on most pharmacokinetic parameters of nadolol, except for an increased half-life in the multiple-dose group. Further research is needed to establish the clinical relevance of this interaction before definitive recommendations on the safety of matcha tea and nadolol coadministration can be made.

Exploring the correlation between knowledge of multiple sclerosis, medication beliefs, access to care and depression in MS patients: a cross-sectional study

Background

Multiple sclerosis (MS) is a common autoimmune illness that causes inflammation, demyelination and neurological damage. Symptom relief and immunotherapy are part of the treatment, but several healthcare barriers significantly influence outcomes and quality of life.

Objectives

This study aimed to assess different aspects among patients with MS, such as their knowledge of the disease, access to care, medications’ beliefs and depression, and to evaluate any correlations between these variables and their impact on the presence of depression.

Methods

A cross-sectional study was conducted from May 2024 to October 2024 at Al-Basheer Hospital, King Abdullah University Hospital (KAUH), Princess Basma Teaching Hospital and the Multiple Sclerosis Society of Amman. 200 participants were recruited after confirming consent. Data were collected through face-to-face interviews using validated instruments, covering sociodemographics, beliefs about medicines, knowledge about MS, access to care and levels of depression.

Results

This study involved 200 patients with MS with a median age of 36 years, mostly women (70.5%), non-smokers (65%) and insured (77.5%). The majority had high education (58%) but low income (67%), with a mean duration of MS disease of 7.8 years after diagnosis. The majority (79.5%) were unaware of their MS type. Beliefs about medications varied, with 22% accepting, 48.5% ambivalent, 14.5% sceptical and 15% indifferent. Disease knowledge was high, with patients recognising MS as an immune, non-contagious and non-curable disease that affects women more than men. Despite good access to care, a percentage of patients needed to travel long distances for care. Depression affected 58% of participants, and it was influenced by access to care, concerning beliefs, income and education. Other variables such as gender, health insurance, the duration of the disease and the necessity of medications had no significant influence.

Conclusion

In conclusion, patients with MS deal with various challenges, such as difficulties in accessing care, associated with psychological factors such as depression. Addressing these barriers by optimising patients' beliefs about medications, enhancing access to care and focusing on the level of knowledge of the disease is crucial for ensuring better and optimal treatment outcomes, as well as decreasing the risk of depression development.