Effects of Green Tea Extracts on Gastric Mucosal Protection

The investigators conduct a randomized, double-blind, placebo-controlled pilot study to investigate the effects of a combined extract of green tea seed (saponins) and green tea leaves (epigallocatechin-3-gallate) on gastric mucosal protection in adults with functional dyspepsia for 8 weeks.

A previous study has indicated that combined extract of green tea seed (saponins) and green tea leaves (epigallocatechin-3-gallate) may improve gastric mucosal status in rat with alcohol-induced gastritis.Therefore, the investigators conduct a randomized, double-blind, placebo-controlled pilot study to investigate the effects of a combined extract of green tea seed (saponins) and green tea leaves (epigallocatechin-3-gallate) on gastric mucosal protection in adults with functional dyspepsia for 8 weeks; the safety of the compound are also evaluated. The Investigators examine C-reactive protein, IFN-γ, TNF-α, gastrin, malondialdehyde, 8-hydroxy-2' -deoxyguanosine, and questionnaires (Gastrointestinal Symptom Rating Scale, Nepean dyspepsia index-Korean version, Nepean dyspepsia index-Korean version QOL questionnaire, Gastrointestinal symptom scale) at baseline and after 8 weeks of intervention. Twenty four adults were administered either 320 mg of combined extracts of green tea seed (saponins) and green tea leaves (epigallocatechin-3-gallate) or a placebo each day for 8 weeks.

Eligibility Criteria:
Inclusion Criteria:

* The Rome IV criteria define dyspepsia as any combination of 4 symptoms: postprandial fullness, early satiety, epigastric pain, and epigastric burning that are severe enough to interfere with the usual activities and occur at least 3 days per week over the last 3 months

Exclusion Criteria:

* Patients complaining of severe gastrointestinal symptoms requiring immediate medication
* Those with a history of gastric acid hypersecretion such as Zollinger-Ellison Syndrome
* Those who received Helicobacter pylori eradication therapy within 4 weeks
* Those who have taken nonsteroidal anti-inflammatory drugs, steroid drugs or antibiotics, aspirin or antithrombotic drugs, or gastric acid suppressants within 4 weeks
* Those who have a history of upper gastrointestinal tract surgery, stenosis, bleeding, esophageal dilatation, gastric mucosal resection, etc. within the past 1 year
* Patients with gastric ulcer (active or healing), duodenal ulcer (active or healing), reflux esophagitis (LA B or higher), or malignant tumors from gastroscopy performed within the last 6 months
* Abnormal liver or renal function (more than twice the normal upper limit of the research institute)
* Uncontrolled diabetes mellitus (\>160 mg/dL of fasting blood sugar)
* History of fracture during the previous year
* Uncontrolled hypertension (\>160/100 mmHg)
* Uncontrolled thyroid diseases.
* History of serious cerebro-cardiovascular diseases or cancer such as angina or myocardial infarction within 6 months
* History of any central bone fracture within 1 year
* History of medication for psychiatric diseases such as severe depression, schizophrenia, drug intoxication.
* Alcohol abuser
* Allergic reaction to Ishige Okamurae
* Those who participated in other drug clinical trials within 1 month from the screening date.
* Severe gastrointestinal symptoms such as heartburn and indigestion
* Those who are pregnant, lactating, or plan to become pregnant during the clinical trial
* Those who are judged to be unsuitable by the PI for other reasons