Negligible pharmacokinetic interaction of red ginseng and antihypertensive agent amlodipine in Sprague-Dawley rats

Surgical Interventions Following Radiotherapy in Spinal Metastases with Intermediate Instability: A Risk Factor Analysis: The Korean Society of Spinal Tumor Multicenter Study (KSST 2022-02)

BACKGROUND

One important determinant in choosing a treatment modality is spinal instability. Clear management guidelines are suggested for stable and unstable spinal metastatic lesions, but lesions in the intermediate instability category (SINS [spinal instability neoplastic score] score of 7-12) remain a clinical dilemma. This study aims to analyze the risk factors necessitating surgical intervention after radiotherapy (RT) in patients with those lesions.

METHODS

A multicenter cohort of 469 patients with spinal metastases of intermediate instability who received radiotherapy (RT) as the initial treatment between 2019 and 2021 were retrospectively enrolled. All patients were neurologically intact at the time of RT. According to the performance of surgical intervention after RT, various clinical and radiographic risk factors for surgical intervention were compared between surgery and non-surgery groups using uni- and multivariate analyses. A recursive partitioning analysis (RPA) was performed using significant determinants identified in multivariate analysis.

RESULTS

The mean age at the time of RT was 59.9 years and there were 198 females. The lung was the most common primary site. During the mean follow-up duration of 18.2 months, surgical treatment was required in 79 (17.9%) of patients. The most common surgical method was decompressive laminectomy with stabilization (62.0%), followed by vertebrectomy with stabilization (22.8%) and stabilization only (15.2%). The mean SINS for the total cohort was 9.0. Multivariate regression analyses revealed that the primary tumor site of the lung, liver, and kidney, higher Bilsky grades of ESCC, lytic bone lesions, and higher EQD210 were significant risk factors for surgical intervention after RT. Among them, Bilsky grade, primary tumor type of the lung, liver, and kidney, and EQD210 were the most important determinants for expecting the probability of surgical intervention on RPA.

CONCLUSIONS

Surgical intervention was performed in 17.9% of patients with intermediate instability after RT as the initial treatment. The primary tumor site of the lung, liver, and kidney, higher Bilsky grade of ESCC, and EQD210 were the most important determinants for expecting the probability of surgical intervention. Therefore, the optimal treatment strategy needs to be devised by carefully evaluating the risk of surgical intervention.

Cardiovascular Effects of Herbal Products and Their Interaction with Antihypertensive Drugs-Comprehensive Review

Hypertension is a highly prevalent population-level disease that represents an important risk factor for several cardiovascular complications and occupies a leading position in mortality statistics. Antihypertensive therapy includes a wide variety of drugs. Additionally, the potential antihypertensive and cardioprotective effects of several phytotherapy products have been evaluated, as these could also be a valuable therapeutic option for the prevention, improvement or treatment of hypertension and its complications. The present review includes an evaluation of the cardioprotective and antihypertensive effects of garlic, Aloe vera, green tea, Ginkgo biloba, berberine, ginseng, Nigella sativa, Apium graveolens, thyme, cinnamon and ginger, and their possible interactions with antihypertensive drugs. A literature search was undertaken via the PubMed, Google Scholar, Embase and Cochrane databases. Research articles, systematic reviews and meta-analyses published between 2010 and 2023, in the English, Hungarian, and Romanian languages were selected.

Simultaneous Analysis of a Combination of Anti-Hypertensive Drugs, Fimasartan, Amlodipine, and Hydrochlorothiazide, in Rats Using LC-MS/MS and Subsequent Application to Pharmacokinetic Drug Interaction with Red Ginseng Extract

Fimasartan, amlodipine, and hydrochlorothiazide are commonly used in combination therapies as antihypertensive drugs. This study aimed to develop and validate an analytical method for fimasartan, its active and major metabolite fimasartan-amide, amlodipine, and hydrochlorothiazide in rat plasma using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The standard calibration curves for fimasartan (1−500 ng/mL), its active and major metabolite fimasartan-amide (0.3−100 ng/mL), amlodipine (0.5−200 ng/mL), and hydrochlorothiazide (5−5000 ng/mL) were linear with R2 > 0.9964, and the inter- and intra-day accuracy and precision and stability were within the acceptable criteria. Using this validated analytical method, the pharmacokinetic interaction of these triple combination drugs between single administration and concomitant administration of the triple combination was investigated; the results did not reveal a significant difference in any of the pharmacokinetic parameters. Based on these results, we investigated the effects of red ginseng extract (RGE) on the pharmacokinetics of fimasartan, fimasartan-amide, amlodipine, and hydrochlorothiazide after oral administration of the combination in rats. No significant difference was observed in the pharmacokinetic parameters of fimasartan, fimasartan-amide, amlodipine, and hydrochlorothiazide, except for the Tmax values of amlodipine. The delayed Tmax value of amlodipine was attributed to its decreased intestinal permeability after repeated RGE treatments. In conclusion, using a combination of antihypertensive drugs and simultaneous analytical methods, we established efficient drug interaction and toxicokinetic studies using a small number of animals.

In Vitro Antioxidant, Anti-Inflammatory and Skin Permeation of Myrsine africana and Its Isolated Compound Myrsinoside B

Dermal aging is characterized by states of oxidative stress, chronic inflammation, and abnormal proteolytic degradation due to the action of hydrogen peroxide, superoxide, 5-lipoxygenase, and elastase, respectively. Noteworthy elastase inhibition has previously been reported, and so this study aimed to investigate the ability of Myrsine africana and myrsinoside B to reduce the activity of hydrogen peroxide, superoxide, and 5-lipoxygenase as supplementary mechanisms of action by which M. africana may reduce the appearance of wrinkles. The use of maltose microneedles were also investigated as a means to enhance the delivery of myrsinoside B into the skin as this is a crucial aspect to investigate when characterizing the efficacy of an active ingredient. Myrsine africana has traditionally been used for skin allergies, boils, and to purify blood (as an astringent) and was selected for this study based on it use in skincare. The crude extract exhibited IC₅₀'s of 56.08 ± 2.88 and 132.74 ± 1.64 µg/ml against the hydrogen peroxide and superoxide radicals, while myrsinoside B exhibited IC₅₀'s of 52.19 ± 4.16 and 192.14 ± 3.52 µg/ml, respectively. The IC₅₀ of the extract and compound against 5-lipoxygenase was 29.65 ± 2.92 and 29.33 ± 3.08 µg/ml, respectively. No toxicity was observed in vitro at the highest concentration tested. Microneedle treatment increased the permeation of the active through the skin after 24 h to 12.46 ± 5.14 µg/cm² compared to the passive group (1.30± 0.85 µg/cm²). The amount of active retained in the epidermis and dermis was 8.97 ± 0.90 and 6.98 ± 0.73 µg/cm² respectively, greater than the retention observed in the passive group (3.24 ± 1.41 and 3.27 ± 1.47 µg/cm², respectively). M. africana and myrsinoside B showed promising antioxidant and anti-inflammatory activity thus supporting the potential of M. africana and myrsinoside B as anti-wrinkle agents. Further, treatment of dermatomed human skin with maltose microneedles facilitated topical delivery of myrsinoside B and provided an effective means for compound delivery to ensure maximum effect.

Effects of Danshen tablets on pharmacokinetics of amlodipine in rats

CONTEXT

Danshen tablets (DST), an effective traditional Chinese multi-herbal formula, are often combined with amlodipine (ALDP) for treating coronary heart disease.

OBJECTIVE

This study investigated the effects of DST on the pharmacokinetics of ALDP and the potential mechanism.

MATERIALS AND METHODS

The pharmacokinetics of ALDP (1 mg/kg) in male Sprague-Dawley rats (n = 6), with or without pretreatment of DST (100 mg/kg for 7 d), were investigated using LC-MS/MS. The effects of DST on the metabolic stability of ALDP were also investigated using rat liver microsomes (RLM).

RESULTS

The results indicated that C_max (16.25 ± 2.65 vs. 22.79 ± 2.35 ng/ml), AUC_(0-t) (222.87 ± 59.95 vs. 468.32 ± 69.87 n gh/ml), and t_1/2 (10.60 ± 1.05 vs. 14.15 ± 1.59 h) decreased significantly when DST and ALDP were co-administered, which suggested that DST might influence the pharmacokinetic behaviour of ALDP when they are co-administered. The metabolic stability of ALDP was also decreased (23.6 ± 4.7 vs. 38.9 ± 5.2) with the pretreatment of DST.

DISCUSSION AND CONCLUSIONS

This study indicated that DST could accelerate the metabolism of ALDP in RLM and change the pharmacokinetic behaviours of ALDP. Accordingly, these results showed that the herb-drug interaction between DST and ALDP might occur when they were co-administered. Therefore, the clinical dose of ALDP should be increased when DST and ALDP are co-administered.

Risk factors for vertebral compression fracture after spine stereotactic body radiation therapy: Long-term results of a prospective phase 2 study

PURPOSE

To identify frequency, clinical relevance and risk factors for vertebral compression fracture (VCF) after spine stereotactic body radiation therapy (SBRT) with long-term follow up (FU).

METHODS

From 2012 to 2015, 61 lesions (56 patients) were treated within a prospective multicenter phase 2 study (NCT01594892) of SBRT for painful vertebral metastases. Post-SBRT VCF were identified. Anatomical segments, normal and tumor tissue of treated vertebrae were segmented for volumetric analyses. Predictive factors for VCF were identified by logistic regression.

RESULTS

Median clinical and radiological FU for all patients was 16.2 months (range, 0-68.2) and 7.8 months (range, 0-66.9), respectively. Local metastasis control was observed in 82% of lesions at last imaging FU. Post-SBRT VCF occurred in 21 lesions (34.4%): 16.4% showed a progressive VCF, while a new VCF occurred in 18.0%. 3/56 (5.4%) patients developed painful VCF defined as pain increase by ≥2 on the visual analogue scale (VAS) and 2 (3.6%) patients required surgical stabilization. Pre-SBRT VCF, localization in the thoracic spine, Bilsky score >0, SINS score, pre-SBRT osteolytic volume and metastatic vertebral body (VB) involvement were predictive factors for VCF on univariate analysis. Relative VB involvement, osteolytic volume and pre-SBRT VCF remained in the multivariate logistic regression model that had AUC = 0.930, 83.3% sensitivity and 96.6% specificity.

CONCLUSION

Spine SBRT resulted in favorable long-term pain and local metastasis control. Despite post-SBRT VCF being observed after one third of treatments, this was symptomatic in only 5% of patients. Predictive factors for developing VCF were identified which could contribute to better selection of patients for spine SBRT.

Effects of triptolide on pharmacokinetics of amlodipine in rats by using LC-MS/MS

CONTEXT

Triptolide and amlodipine are often simultaneously used for reducing urine protein excretion after renal transplantation in China clinics.

OBJECTIVE

This study investigated the effects of triptolide on the pharmacokinetics of amlodipine in male Sprague-Dawley rats.

MATERIALS AND METHODS

The pharmacokinetics of amlodipine (1 mg/kg) with or without triptolide pre-treatment (2 mg/kg/day for seven days) were investigated using a sensitive and reliable LC-MS/MS method. Additionally, the inhibitory effects of triptolide on the metabolic stability of amlodipine were investigated using rat liver microsome incubation systems.

RESULTS

The results indicated that when the rats were pre-treated with triptolide, the Cmax of amlodipine increased from 13.78 ± 3.57 to 19.96 ± 4.56 ng/mL (p < 0.05), the Tmax increased from 4.04 ± 1.15 to 5.89 ± 1.64 h (p < 0.05), and the AUC0-t increased by approximately 104% (p < 0.05), which suggested that the pharmacokinetic behaviour of amlodipine was affected after oral co-administration of triptolide. Additionally, the metabolic half-life was prolonged from 22.5 ± 4.26 to 36.8 ± 6.37 min (p < 0.05) with the pre-treatment of triptolide.

CONCLUSIONS

In conclusion, these results indicated that triptolide could affect the pharmacokinetics of amlodipine, possibly by inhibiting the metabolism of amlodipine in rat liver when they are co-administered.

Effect Of epigallocatechin-3-gallate on the pharmacokinetics of amlodipine in rats

This study investigates the effect of epigallocatechin-3-gallate (EGCG), a major ingredient of green tea, on the pharmacokinetics of amlodipine in rats. The pharmacokinetics of orally administered amlodipine (1 mg/kg) with or without EGCG pretreatment (30 mg/kg/day for 10 days) were investigated. Plasma concentrations of amlodipine were determined by using a sensitive and reliable liquid chromatography with tandem mass spectroscopy (LC-MS/MS) method. The effects of EGCG on the metabolic stability of amlodipine were investigated by using rat liver microsome incubation systems. The results indicated that when the rats were pretreated with EGCG, the C_max of amlodipine increased from 16.32 ± 2.57 to 21.44 ± 3.56 ng/mL (p < 0.05), the T_max decreased from 5.98 ± 1.25 to 4.01 ± 1.02 h (p < 0.05), and the AUC_0-t increased from 258.12 ± 76.25 to 383.34 ± 86.95 μg h L^-1 (p < 0.05), which suggested that the pharmacokinetic behavior of amlodipine was affected after oral co-administration of EGCG. Additionally, the metabolic half-life was prolonged from 31.3 ± 5.6 to 52.6 ± 7.9 min (p < 0.05) with the pretreatment of EGCG. It can be speculated that the drug-drug interaction between EGCG and amlodipine might occur, which might have resulted from the metabolism inhibition of amlodipine by EGCG when they were co-administered.

Evaluation of lignan (-)-cubebin extracted from Piper cubeba on human colon adenocarcinoma cells (HT29)

The dibenzylbutyrolactone lignan (-)-cubebin, which is extracted from the seeds of the pepper Piper cubeba, has shown promise as an anti-inflammatory, analgesic, leishmanicidal, antiproliferative, and trypanocidal compound. Given the therapeutic potential of (-)-cubebin, this study aimed to investigate its safety profile by analyzing cytotoxicity, mutagenicity, cell proliferation kinetics, induction of apoptosis, and expression of pro-apoptotic genes in human colon adenocarcinoma cells (HT29) exposed to (-)-cubebin. MTT cytotoxicity assays demonstrated that (-)-cubebin was cytotoxic only at 280 µM, whereas it was not cytotoxic at 2.8, 14, or 28 µM. Data demonstrated that (-)-cubebin was not mutagenic as evidenced by a micronucleus (MN) assay, did not alter cell-growth kinetics over 4 d, and showed absence of induced apoptosis after 24 h. Further, CASP8 and CASP9 gene expression was not markedly changed in HT29 cells exposed to 28 µM or 70 µM (-)-cubebin for 12 h. Based on our observations, (-)-cubebin was cytotoxic at a concentration of 280 µM, suggesting that the use of this concentration should be avoided. However, lower concentrations exerted no apparent damaging effects, indicating that this lignan is safe to use for pharmacological purposes at certain concentrations.

Negligible Pharmacokinetic Interaction of Red Ginseng and Losartan, an Antihypertensive Agent, in Sprague-Dawley Rats

Red ginseng (RG) is one of the top selling herbal medicines in Korea, but is not recommended in hypertensive patients. In this study, the pharmacokinetic (PK) interaction between RG and losartan, an antihypertensive drug, was examined. RG was orally administered for 2 wk to male Sprague-Dawley (S-D) rats at either control (0), 0.5, 1, or 2 g/kg/d for 2 wk. After the last administration of RG and 30 min later, all animals were treated with 10 mg/kg losartan by oral route. In addition, some S-D rats were administered RG orally for 21 d at 2 g/kg followed by losartan intravenously (iv) at 10 mg/kg/d. Post losartan administration, plasma samples were collected at 5, 15, and 30 min and 1, 1.5, 2, 3, 6, 12, and 24 h. Plasma concentrations of losartan and E-3174, the active metabolite of losartan, were analyzed by a high-pressure liquid chromatography-tandem mass spectrometer system (LC-MS/MS). Oral losartan administration showed dose-dependent pharmacokinetics (PK) increase with time to maximum plasma, but this was not significant between different groups. There was no significant change in tmax with E-3174 PK. With iv losartan, pharmacokinetics showed elevation of area under the plasma concentration-time curve from time zero extrapolated to infinitity. There was not a significant change in AUCinf with E-3174 PK. Therefore, RG appeared to interfere with biotransformation of losartan, as RG exerted no marked effect on E-3174 PK in S-D rats. Data demonstrated that oral or iv treatment with losartan in rats pretreated with RG for 2 wk showed that losartan PK was affected but E-3174 PK remained unchanged among different dose groups. These results suggested that RG induces negligible influence on losartan and E-3174 PK in rats.