The Absorption of Bioactive Berberine in Human
Condition: Healthy
Study type: Interventional

Summary: 
      Berberine from medicinal plants has therapeutic activities against multiple chronic diseases.
      But its absorption rate is very low. The objective of this study is to test if adding TPGS or
      Quillaja extract as an emulsifier enhance the absorption of berberine in human.
    

Detailed description: 
      Berberine is widely used as an herbal medicine and many health benefits. These
      well-documented in the literature including lowering blood lipids and glucose, having
      anti-inflammatory and anti-tumor activity, preventing and delaying neurodegenerative diseases
      (Alzheimer, Parkinson and Huntington disease) and preventing obesity. However, the absorption
      rate of berberine is very low. The study team believes adding TPGS or Quillaja extract as an
      emulsifier enhance the absorption of berberine in human.

      The bioavailability of berberine is extremely low. Only 0.5% of orally ingested berberine are
      absorbed in small intestine and about 0.36% can enter the systemic circulation. About 56% of
      ingested berberine was not absorbed and additional 43.5% is lost due to metabolism in small
      intestine.

      Vitamin E TPGS (a water-soluble form of vitamin E) is a food additive approved by FDA. It has
      the potential to increase the absorption of drugs and dietary supplements. TPGS is an
      effective inhibitor of P-glycoproteins that are responsible for decreased absorption rate of
      many drugs including berberine. TPGS has the potential be a safe and effective adsorption
      enhancer for berberine and other bioactive botanicals.

      Quillaja extract is a natural GRAS (generally recognized as safe) food-grade
      surfactant/emulsifier ingredient rich in saponins and sapogenins. It is purified from the
      Quillaja Saponaria Molina tree which is native to Chile. Quillaja extract is an approved
      ingredient for use in Food and Beverages by FDA under Title 21 CFR 172.51. It is an approved
      food additive in the European Union under code E 999. Quillaja extract is an attractive
      alternative emulsifier for berberine formulation because it meets consumers' demand for
      natural ingredient. Quillaja extract provides additional benefits of anti-inflammation and
      cholesterol lowering to dietary supplement. Some early study before 2000 suggested that
      Quillaja saponin DS-1 promote the absorption of insulin and aminoglycoside antibiotics via
      the ocular and nasal route by reducing permeability of epithelial barrier. However, it is not
      known whether quillaja affect absorption of berberine in vivo or in human.

      Specific Aims:

        1. To determine whether TPGS or Quillaja extract emulsification increase the
           bioavailability of orally ingested berberine in human volunteers by increasing its
           plasma concentration time curve (AUC), peak concentration (Cmax), and elimination half
           time (T1/2).

        2. To determine whether TPGS or Quillaja extract emulsification alter phase I metabolism,
           phase II metabolism, or metabolism by gut microbiota for orally ingested berberine in
           human

      The hypothesis of this research is that TPGS or Quillaja extract emulsification enhances the
      bioavailability of orally ingested berberine in human by altering it metabolism and
      pharmacokinetic profiles.

      Advertisement will be in the form of flyers. Contact information of investigators will be
      included in the flyer. All participants will be received written and oral information
      regarding the natural and potential risks of the study. The informed consent form will be
      given to the participants to get consent in a private room 7 days before the study.

      Screening, Tolerability Test and Informed Consent: Subject will take two capsules of the
      reference berberine dietary supplement with 8 ounces of room temperature water and subject
      will remain in a fasted state for 4 hours. After completing 4 hours period, a standard lunch
      with water will be served. If subject experiences diarrhea after taking supplement, she/he
      will immediately report to the Principle Investigator, Dr. Wang or the Study coordinator. The
      result of tolerability test will base on the self-assessment of diarrhea. Twelve participants
      will be chosen having no symptoms of diarrhea Experiment process: Participants will be
      advised to avoid berberine, vitamin E TPGS or Quillaja extract supplements and foods,
      excessive amount of alcohol from the beginning of 7-day run in period to the end of the
      study.

      Participants will receive three treatments (A: TPGS emulsified berberine or B:Quillaja
      extract emulsified berberine soft gel and C: berberine reference powder in hard shell
      capsules) using a randomized crossover design. Treatment A, B and C provide an equal amount
      of berberine at 800 mg dose.

      Twelve healthy subjects will be randomly assigned into three groups with 4 in each group.
      Subjects will be asked to collect initial urine samples in an 8-ounce container provided by
      the study team before taking the supplement and the rest of urine samples will be collected
      in a different container after taking supplement for 12 hours period. A trained and certified
      phlebotomist will be hired to draw blood. A catcher will be implanted in the participants
      forearm for blood draw. After a baseline blood sample is taken, four participants in group A
      will receive at two capsules of TPGS emulsified berberine in soft gel (2x400mg) and four
      subjects in group B will receive four capsules of the Quillaja extract emulsified berberine
      (4x200mg) in soft shell capsules, and four participants in group C will receive at two
      capsules of berberine reference powder (2x400mg) in hard shelf. Additional blood samples will
      be drawn at 0.5 h, 1 h, 2 h, 3h, 4 h, 6 h, 8 h and 12 h for analysis of plasma concentrations
      of berberine and berberrubine. In addition, the participants will collect all urine samples
      in a gallon size plastic container during 12 h after the initial dose. A standard breakfast
      of plain bagel with cream cheese will be given to each participant between 0.5 h and 1 h
      blood draw. After 4 h blood draw, subjects will be given an identical meal for lunch.
      Immediately after collection, blood samples will be centrifuged and plasma will be stored at
      -80 degrees C until analysis. The urine samples will be stored at -80 degrees C until
      analysis. After two 7-day washout period, the process will be repeated with each group
      switching over to the other treatment, that is, the group that received treatment A will take
      treatment B or C and the group that received treatment B will take treatment A or C, the
      group that received treatment C will take treatment A or B.

      Berberine and dihydroberberine in blood exist in nonconjugate free form. A major metabolite
      berberrubine exists in free form and phase II metabolites including sulfates and glucuronide.
      In order to analyze berberrubine in all forms, a portion of plasma or urine will be treated
      with β-glucuronidase from Helix pomatia to hydrolyze its sulfate/glucuronides. Berberine and
      berberrubine will be extracted from plasma or urine with or without enzyme treatment using
      solvent or solid phase extraction. The compounds' concentration will be determined using
      HPLC-ESI-MS/MS method. Pharmacokinetic parameters such as area under the plasma concentration
      time curve (AUC), peak concentration (Cmax), time at peak concentration (Tmax), and
      elimination half time (T1/2) will be calculated for berberines, free berberrubine, and total
      berberrubine. Relative absorption will be expressed as the ratio of calculated AUC's.
    

Intervention name(s): Berberine; TPGS emulsified berberine; Quillaja extract emulsified berberine
Intervention type(s): Dietary Supplement; Dietary Supplement; Dietary Supplement
Intervention description(s): Two capsules of berberine. Each capsule contains 400 mg berberine. The total amount of berberine throughout is 800 mg.; Two capsules of TPGS/Quillaja extract emulsified berberine. Each capsule contains 400 mg berberine. The total amount of berberine throughout is 800 mg.; Four capsules of Quillaja extract emulsified berberine. Each capsule contains 200 mg berberine. The total amount of berberine throughout is 800 mg.
Other intervention name(s): Berb-Evail
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Single (Participant)
Primary purpose: Basic Science
Keywords: Berberine; TPGS; Pharmacokinetics; Human intervention study; Quillaja extract