What herbal teas are good for allergies

Abstract

Herbal teas such as those made from Houttuynia cordata own been consumed for generations for health promotion. Herbal teas contain numerous ingredients, and there is concern that herbal teas can affect the pharmacokinetics of drugs. In this study we examined the effect of herbal teas on drug permeability. We used the human colon carcinoma cell line Caco-2 as a model to study the permeability of two drugs across the intestinal cell membrane. We quantified of the quantity of digoxin and verapamil passed from apical to basal membranes of Caco-2 cells with and without extracts (1 mg/mL or 10 mg/mL) of four diverse teas (Rubus suavissimus S.

Lee, Ginkgo biloba, Houttuynia cordata, and Eucommia ulmoides). These extracts were made with boiling water and dried. For our experiments, the dried extracts were resuspended in water. Our results showed that extracts from Rubus suavissimus S. Lee, Houttuynia cordata, and Eucommia ulmoides at a concentration of 1 mg/mL or 10 mg/mL did not affect digoxin permeability from apical to basal membranes of Caco-2 cells.

What herbal teas are excellent for allergies

However, an extract from Ginkgo biloba at a concentration of 10 mg/mL significantly increased permeability of digoxin and verapamil. Though this concentration is higher than that of typical tea preparations, Ginkgo biloba extract may exert this effect by inhibiting drug export P-glycoprotein (P-gp) since both digoxin and verapamil are known to be transported by P-gp.


Discussion

Findings regarding interactions between functional foods and medicines will be dependent on each medicine.

For example, approximately 40 functional foods modulate the effects of warfarin [13]. However, the information available regarding interactions between functional foods and medicines is limited [14].

What herbal teas are excellent for allergies

To our knowledge, medical manuals rarely mention foods that can interact with medicines, other than the well-documented examples of grapefruit juice (GFJ) [15,16] and St. John's wort (Hypericum perforatum.) [17]. Among four kinds of teas used in this study, only Ginkgo biloba has been reported to interact with medicines [18].

The concentrations of extracts for normal drinking is 1.2-3.6 mg/mL, thus the effective concentration of extracts used in this study, 10 mg/mL (Figure 1), is 2.8-8.3 times higher than the concentration of extracts consumed in normal tea drinking. Eucommia ulmoides, Houttuynia cordata, and Rubus suavissimus S.

Lee did not significantly affect the levels of digoxin transport from apical to basal membranes (Figure 1B, C, D). Therefore, our results show that consumption of herbal tea prepared in normal concentrations should not affect the transport of drugs by P-gp.

In contrast, Ginkgo biloba extract increased digoxin permeability from the apical to basal membrane in a dose-dependent manner (Figure 1A). Ginkgo biloba extract also increased verapamil permeability (Figure 2).

Thus, Ginkgo biloba extract may exert this effect by inhibiting export by P-gp on the apical side. These results are in accord with those of Wang et al. [19], who showed that flavonoids in Ginkgo biloba inhibited the function of P-gp [19]. The effect of Ginkgo biloba extract on P-gp may be negligible, because the effective concentration (10 mg/mL) is greater than the concentration (3.6 mg/mL) of typical tea preparations.

Inhibition and induction of the metabolic enzyme CYP can also affect the pharmacokinetics of treatment with these medications.

This should be of concern since CYP3A4 is associated with the metabolism of numerous drugs. It is well known that there is overlap in the substrate specificities of CYP3A4 and P-gp [20]. Thus, substrates of P-gp might significantly affect pharmacokinetics.

What herbal teas are excellent for allergies

GFJ affects the function of CYP3A4 and P-gp [16]. In addition, catechins in green tea (Camellia sinensis) affect the function of CYP3A4 and P-gp in vitro [21]. Moreover, it has been reported that an extract of Ginkgo biloba inhibited the function of CYP3A4 and P-gp [19, 22]. However, a clinical study in Korea has shown that pharmacokinetics of cilostazol was not affected significantly when used with Ginkgo biloba [23]. In addition, herbs are used as alternative medicine in 30-70% of patients treated for cancer in Germany, and it has been evaluated that Ginkgo biloba can be used with drugs safely [24].

Thus, the foods that contain ingredients that can inhibit metabolic enzymes and/or drug transport proteins in vitro may not affect pharmacokinetics.

It is necessary to examine the effects of the chronic intake of functional foods, even if single consumption does not affect pharmacokinetic parameters. For example, dietary supplement ingredients to rats for four weeks affected the maximum concentration in blood digoxin levels (Cmax) and the area under the blood concentration-time curve (area under the curve, AUC) [25]. It has been reported that chronic exposure of cancer cells to kaempferol significantly increased glutathione S-transferase activity and reduced the effect of anticancer agents, although this was an in vitro study [26].

In conclusion, since the concentrations of tea extracts (10 mg/mL) used in this study were 2.8-8.3 times higher than the concentration for normal drinking, the effects of these four teas on the absorption of drugs can be disregarded.

However, it is still significant to examine the effects of chronic intake of herbal teas on both pharmacokinetics and effects of drugs in vivo.


Materials and methods

1 Materials

Digoxin and verapamil were obtained from SIGMA-ALDRICH (St. Louis, MO, USA) and Wako (Osaka, Japan), respectively. Dried products (3-5 g) in tea Ginkgo biloba (Kenko Foods, Yokohama, Japan), Eucommia ulmoides (Kobayashi Pharmaceuticals, Osaka, Japan), Houttuynia cordata (Honzo, Nagoya, Japan), or Rubus suavissimus S. Lee (Honzo, Nagoya, Japan) were extracted by incubation with 500 mL of boiling water at 100 °C for 5 min.

The extracts were vacuum-concentrated to a volume of 20 mL, and 1 mL of each vacuum-concentrated solution was evaporated to dryness. The evaporation residue was weighed to calculate the concentrations of extracts of herbal teas. The vacuum-concentrated extracts of each herbal tea was prepared to be 1 mg/mL or 10 mg/mL in Hanks’ balanced salt solution containing 10 mM HEPES (pH 7.4) (Figs. 1, 2).

3 Quantifications of digoxin and verapamil

Digoxin (final conc. 2 µM) or verapamil (final conc.

20 µM) was added to the apical chamber in the absence or presence of herbal tea extract. After 2 h, 1 mL of the medium from the basal chamber was collected.

What herbal teas are excellent for allergies

0.5 mL of 200 mM phosphate buffer (pH 9.3) and 1 mL of an ethyl acetate/hexane/dichloromethane (3:1:1, v/v) mixture were added. After 10 minutes of shaking, samples were centrifuged (10,000 × g, 4°C, 10 minutes). A volume of 0.5 mL of the upper organic layer was transferred to a tube and evaporated to dryness under airflow at 40°C. The evaporated residues were dissolved in 100 µL of water/ CH3CN (7:3, v/v) mixture and used as samples for HPLC quantification.

Digoxin (Figure 1) was quantified by HPLC (Shimazu, SPD-M20A) with a 100 mm × φ4.6 mm, 3 μm ODS column (Unison UK-C18, Imtakt) with a flow rate of 0.8 mL/min using water/CH3CN (7:3); absorbance at 220 nm was monitored.

Verapamil (Figure 2) was quantified by HPLC with a flow rate of 1.0 mL/min using 100 mM AcONH4/CH3CN (6:4); absorbance at 235 nm was monitored.

Figure 1.

What herbal teas are excellent for allergies

Effect of herbal tea extracts on digoxin permeability. Values are mean ± S.E. n = 4 for each treatment. Significant difference (*: p < 0.05 vs control, Williams’ test)

2 Cell culture

Cultures of the human colon carcinoma cell line Caco-2 were obtained from ATCC (Manassas, VA, USA) and were maintained in DMEM supplemented with 10% FBS, 100 units/mL penicillin, and 100 μg/mL streptomycin at 37°C under 5% CO2. To form a monolayer of CaCo-2 cells, 1 × 105 cells were plated into 12-well Transwell plates with pore size of 3.0 µm (Corning, Corning, NY, USA) for 21 days at 37°C under 5% CO2.

The culture medium was changed every 2-3 days.

4 Statistical analysis

Results of multiple observations are presented as means ± SEM. One-way analysis of variance (ANOVA) followed by the Williams’ test was used for multiple comparisons. p < 0.05 was considered significant.


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    What herbal teas are excellent for allergies

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I’ve always had beautiful gnarly allergies, but this year has been killer—I sneeze far more often than my co-workers and my easily startled cat would love and am constantly reminding myself not to screw up my mascara by rubbing my eyes (apparently, it’s not just me, as climate change is making allergies worse for everyone).

While I’ve dabbled in the world of over-the-counter allergy medications, I prefer to veer to more natural remedies—I’m every about pain relief for, tell, a one-off headache, but allergies are a daily problem!

Because I’m the tea equivalent of a pack-a-day smoker (a box a day? Ten bags a day? I don’t know; I own a problem), tea seemed love the perfect solution. A bit of research led to me nettle tea, which has been proven in multiplestudies to reduce the symptoms of allergies.

Otherwise known as «that plant that attacks your legs when you attempt to go hiking,» nettle (or stinging nettle, as it’s affectionately known) is an anti-inflammatory powerhouse, allowing it to attack allergies at their root (i.e., inflammation) and letting you get on with your life.

As a extremely significant bonus, when it’s dried and made into a tea, it loses its pain-inducing properties, which is fairly vital for having a relaxing cuppa.

The only problem?

Nettle is grassy, and not in a pleasant, I’m-frolicking-in-a-meadow way. I bought a bunch of loose-leaf tea from a local herb store and had to almost hold my nose as I drank it. I got it below (see above note about my tea addiction; it’s extremely, extremely real) but I didn’t enjoy it. The only upside? My allergies got noticeably better. In about a week of drinking a cup or two a day, my eyes stopped itching and I went from blowing my nose upward of 10 times a day to blowing it once or twice.

And then I found The Republic of Tea’s Peppermint Vanilla Nettle mix. You guys. This tea. The subtle grassiness of the nettle is still there but it’s brought to life by the fragrant vanilla (vanilla is actually one of the flavors your brain perceives as sweetness, so including it in anything is a grand way to impart that treat quality without adding any sugar) and the unused peppermint.

It is, fairly simply, the best tea I’ve ever tasted (and smelled!). Everyone who’s ever tried it is obsessed (I can’t hold it stocked on my desk at the office)—and, after I switched from my local nettle tea to this one, the allergy-calming benefits kept correct on going. This is the smoothest I’ve ever sailed through spring.

Bottom line: Get thyself Peppermint Vanilla Nettle Tea. If you can’t get that, get thyself some plain nettle tea (and maybe steep it with a peppermint tea bag, and a pinch of vanilla powder or dash of vanilla extract).

If you can’t stomach that, use turmeric (also massively anti-inflammatory) and local honey (which inoculates you against pollens from your area, love an oh-so-sweet vaccine) in some water and call it a day. Jessica Cording, a registered dietitian, also recommends avoiding dairy and taking a probiotic supplement if you’re prone to allergies. «This helps populate the GI tract with beneficial bacteria that can assist our body function at its best and potentially reduce the severity of those symptoms,» she says. «While it’s not conclusive or shown to be a cure-all, having a healthy gut is significant for overall wellness, so allergy season is a grand time to make certain you’re on point with that.»

P.S.: When you steep any herbal tea you’re hoping to derive therapeutic benefits from, cover it while it steeps and let it sit for at least 10 minutes.

This way, the volatile organic compounds that make the tea so powerful don’t escape in the form of steam. Don’t tell I never taught you anything.

We’ve every had one of those nights, or maybe even a few, where we just can’t seem to catch some really excellent Z’s or drop asleep at every for that matter. We sometimes lay there for hours upon hours just thinking about the day and every of the stress in our lives, which is no excellent for our health or our hearts.

So, rather than pumping your body full of sleeping pills or taking a sleep aid that does more damage than good, try a natural herbal route, such as chamomile tea.

This powerful herb has a wide variety of benefits for you that you may not even be aware of. It’s one of the most versatile medicinal herbs known to man thanks to its antioxidants for disease-fighting and sleep assistance properties.

I’ve always had beautiful gnarly allergies, but this year has been killer—I sneeze far more often than my co-workers and my easily startled cat would love and am constantly reminding myself not to screw up my mascara by rubbing my eyes (apparently, it’s not just me, as climate change is making allergies worse for everyone).

While I’ve dabbled in the world of over-the-counter allergy medications, I prefer to veer to more natural remedies—I’m every about pain relief for, tell, a one-off headache, but allergies are a daily problem!

Because I’m the tea equivalent of a pack-a-day smoker (a box a day? Ten bags a day? I don’t know; I own a problem), tea seemed love the perfect solution. A bit of research led to me nettle tea, which has been proven in multiplestudies to reduce the symptoms of allergies.

Otherwise known as «that plant that attacks your legs when you attempt to go hiking,» nettle (or stinging nettle, as it’s affectionately known) is an anti-inflammatory powerhouse, allowing it to attack allergies at their root (i.e., inflammation) and letting you get on with your life.

As a extremely significant bonus, when it’s dried and made into a tea, it loses its pain-inducing properties, which is fairly vital for having a relaxing cuppa.

The only problem?

Nettle is grassy, and not in a pleasant, I’m-frolicking-in-a-meadow way. I bought a bunch of loose-leaf tea from a local herb store and had to almost hold my nose as I drank it. I got it below (see above note about my tea addiction; it’s extremely, extremely real) but I didn’t enjoy it. The only upside? My allergies got noticeably better. In about a week of drinking a cup or two a day, my eyes stopped itching and I went from blowing my nose upward of 10 times a day to blowing it once or twice.

And then I found The Republic of Tea’s Peppermint Vanilla Nettle mix.

You guys. This tea. The subtle grassiness of the nettle is still there but it’s brought to life by the fragrant vanilla (vanilla is actually one of the flavors your brain perceives as sweetness, so including it in anything is a grand way to impart that treat quality without adding any sugar) and the unused peppermint. It is, fairly simply, the best tea I’ve ever tasted (and smelled!). Everyone who’s ever tried it is obsessed (I can’t hold it stocked on my desk at the office)—and, after I switched from my local nettle tea to this one, the allergy-calming benefits kept correct on going.

What herbal teas are excellent for allergies

This is the smoothest I’ve ever sailed through spring.

Bottom line: Get thyself Peppermint Vanilla Nettle Tea. If you can’t get that, get thyself some plain nettle tea (and maybe steep it with a peppermint tea bag, and a pinch of vanilla powder or dash of vanilla extract). If you can’t stomach that, use turmeric (also massively anti-inflammatory) and local honey (which inoculates you against pollens from your area, love an oh-so-sweet vaccine) in some water and call it a day.

Jessica Cording, a registered dietitian, also recommends avoiding dairy and taking a probiotic supplement if you’re prone to allergies. «This helps populate the GI tract with beneficial bacteria that can assist our body function at its best and potentially reduce the severity of those symptoms,» she says. «While it’s not conclusive or shown to be a cure-all, having a healthy gut is significant for overall wellness, so allergy season is a grand time to make certain you’re on point with that.»

P.S.: When you steep any herbal tea you’re hoping to derive therapeutic benefits from, cover it while it steeps and let it sit for at least 10 minutes.

This way, the volatile organic compounds that make the tea so powerful don’t escape in the form of steam. Don’t tell I never taught you anything.

We’ve every had one of those nights, or maybe even a few, where we just can’t seem to catch some really excellent Z’s or drop asleep at every for that matter. We sometimes lay there for hours upon hours just thinking about the day and every of the stress in our lives, which is no excellent for our health or our hearts.

So, rather than pumping your body full of sleeping pills or taking a sleep aid that does more damage than good, try a natural herbal route, such as chamomile tea. This powerful herb has a wide variety of benefits for you that you may not even be aware of.

It’s one of the most versatile medicinal herbs known to man thanks to its antioxidants for disease-fighting and sleep assistance properties.


Key words

P-glycoprotein, verapamil, digoxin, ginkgo biloba, eucommia ulmoides, houttuynia cordata, rubus suavissimus S. Lee


Introduction

In developed countries, the incidence of lifestyle diseases has risen. Increasing interest in health promotion is reflected in rising sales of functional foods and supplements.

What herbal teas are excellent for allergies

The global market for vitamin and mineral supplements and functional foods was estimated in 2011 to be worth approximately USD 25.3 billion [1]. Although the majority of supplement sales were those of vitamins and minerals, a large proportion are functional supplements containing herbs. Herbal teas own been consumed traditionally for protection against disease. The efficacy and effectiveness of ingredients of the herbal teas own been extensively studied, and the effectiveness of herbal teas on hypertension [2], inflammation [3,4], allergies [5], and improvements of brain activity [6] has been documented.

Use of herbal teas for the general purpose of health maintenance does not seem to pose health risks, but concern has arisen regarding potential drug interactions with consumption of herbal teas [7].

It has been reported that more than 80% of patients take some helpful of supplements, with half of those taking supplements other than vitamins and minerals [8]. Potential interactions between supplements and drugs own not been adequately studied [9].

Herbal teas contain medicinal compounds that could interact with other medicines. For example, some herbal medicines contain furanocoumarin that inhibits P-glycoprotein (P-gp), which exports drugs from cells.

Furanocoumarin also inhibits cytochrome P450 (CYP) 3A4, a metabolic enzyme. Furanocoumarin affects the pharmacokinetics parameter of P-gp substrate drugs [10]. It has been shown that licorice root, commonly used as a sweetener, also inhibits P-gp [11,12].

In this study, we investigated the effects of extracts of Ginkgo bioba. Eucommia ulmoides, Houttuynia cordata, and Rubus suavissimus S. Lee on the permeability of the drugs digoxin and verapamil using the human colon carcinoma cell line Caco-2 as a model of intestinal absorption of drugs.


Results

We evaluated the effects of extracts of herbal teas on drug permeability using Caco-2 cell monolayers from the intestinal tract.

We examined the effects of each tea on the transport by P-gp by measuring the quantity of digoxin and verapamil that crossed the treated monolayer.

First, we examined the effects of herbal tea extracts on digoxin permeability from the apical side to the basal side of the Caco-2 cell monolayer. The concentration of each concentrated extract was as follows: Ginkgo biloba, 90 mg/mL; Eucommia ulmoides, 30 mg/mL; Houttuynia cordata, 50 mg/mL; Rubus suavissimus S.

Lee, 50 mg/mL. Digoxin (1.0 nmol) alone or in combination with 1 mg/mL or 10 mg/mL of the Ginkgo biloba, Eucommia ulmoides, Houttuynia cordata, or Rubus suavissimus S. extracts was added to the buffer on the apical side. The quantity of digoxin transported to the basal side was quantified (Figure 1): digoxin alone, 0.33 nmol (33.3%); digoxin with 1 mg/mL of an extract of Ginkgo biloba, 0.39 nmol (39.3%); digoxin with 10 mg/mL of an extract of Ginkgo biloba, 0.47 nmol (46.5%) (Figure 1A).

Thus Ginkgo biloba increased digoxin permeability in a dose-dependent manner. However, the other three kinds of teas did not significantly affect digoxin transport (Figure 1B, C, D).

We also investigated the effect of Ginkgo biloba extract on verapamil transport. Verapamil (10 nmol) alone or in combination with 1 mg/mL or 10 mg/mL of Ginkgo biloba extract was added to the buffer solution on the apical side, and then the quantity of verapamil transported to the basal side was quantified (Figure 2). The quantities of verapamil in the basal side were as follows: verapamil alone, 2.65 nmol (26.5%); verapamil with 1 mg/mL of Ginkgo biloba extract, 2.63 nmol (26.3%); verapamil with 10 mg/mL of Ginkgo biloba extract, 3.37 nmol (33.7%).

Verapamil transport was significantly increased in the presence of 10 mg/mL of Ginkgo biloba extract.

Figure 2. Effect of Ginkgo biloba extract on verapamil permeability. Values are mean ± S.E. n = 3 for each treatment. Significant difference (*: p < 0.05 vs control, Williams’ test)


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