Skip to main content
OpenTrials
Recruiting

NCT Number: NCT07440147

Effects of Akkermansia Muciniphila and Berberine Supplementation on Insulin Sensitivity in Night-shift Workers

Night shift work is associated with an increased risk of obesity, insulin resistance, and cardiometabolic disorders, largely due to circadian misalignment, disrupted sleep, and altered eating patterns. These behavioral and physiological disturbances impair glucose metabolism and are further influenced by the gut microbiota. In particular, the bacterium Akkermansia muciniphila has been linked to improved metabolic health, including enhanced insulin sensitivity, lipid regulation, and maintenance of intestinal barrier integrity. Berberine, a bioactive plant-derived compound, has demonstrated metabolic benefits, including upregulation of A. muciniphila, improvement of insulin sensitivity, and modulation of lipid metabolism.

Together, these complementary mechanisms suggest that combined A. muciniphila supplementation and berberine administration may synergistically improve metabolic health in shift workers by targeting gut microbiota composition and circadian-regulated metabolic pathways.

Based on this rationale, a double-blind, randomized, placebo-controlled, crossover study is being conducted in 200 night-shift workers from healthcare and industrial sectors in Austria and Denmark. Participants are stratified by age, sex, and work sector and randomly assigned to intervention sequences. Each participant receives either the combined supplement or placebo for 12 weeks, followed by a four-week washout, after which the alternate intervention is administered for another 12 weeks, with a total participation of 28 weeks.

Assessments are performed at four study visits and include anthropometry, body composition, blood pressure, and collection of blood, urine, and feces. Participants complete validated questionnaires on dietary intake, lifestyle, work schedules, and general health to monitor behavioral patterns throughout the study. Dietary intake is recorded for four days prior to each sampling visit in consideration of shift schedules. Sleep duration and quality are monitored via diaries and actigraphy and aligned with dietary records. Circadian variation is minimized by standardizing sampling times and implementing a fasting and synchronization period prior to visits.

The primary outcome is insulin sensitivity, measured by HOMA-IR. Secondary exploratory outcomes include gut microbiota composition and diversity, biomarkers of intestinal permeability and inflammation, lipid profiles, body composition, sleep quality, and dietary behavior.

These measures collectively provide a comprehensive evaluation of the metabolic, microbiome, and circadian effects of combined A. muciniphila and berberine supplementation in night-shift workers.

Recruiting

Interested in participating?

Request Info

Key information

Conditions

Obesity & Overweight Body Weight Chronobiology Disorders Circadian Rhythm Disorders Diabetes Mellitus Endocrine System Diseases Glucose Intolerance Glucose Metabolism Disorders Gut Microbiota Modulation Hyperglycemia Hyperinsulinism Insulin Resistance Metabolic Diseases Nervous System Diseases Nutrition Disorders Nutritional and Metabolic Diseases Obesity Overnutrition Overweight Pathological Conditions, Signs and Symptoms Prediabetes (Insulin Resistance, Impaired Glucose Tolerance) Prediabetic State Signs and Symptoms

Age range

21 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

FH JOANNEUM University of Applied Sciences

Graz, Styria, 8020, Austria

Location status: Recruiting

Location contact

Miriam Ressler, PhD

CONTACT

[email protected]

+4331654536677

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Health care or industrial shift worker
  • Employed or self-employed working ≥ 24 h/week
  • Current night shift work (night shift defined as a work schedule that includes at least 3 hours of work between 00:00 and 5:00) with at least 2 consecutive nights/month
  • Night shift work duration > 3 years
  • 4 or more night shifts/month

Exclusion criteria

  • BMI of 40 kg/m² or higher
  • Pregnancy or planned pregnancy within 6 months of enrolment or breastfeeding women
  • Bariatric surgery
  • Surgery in the 3 months prior to the study or planned surgery in the next 6 months that, in the opinion of the investigators, could potentially affect the outcome of the study
  • Diagnosed diabetes type 1 or type 2
  • Uncontrolled thyroid disease (confirmed by clinically significant abnormal TSH/T4 levels without stable medication for more than 3 months)
  • Chronic diseases (renal failure, active hepatitis, liver cirrhosis, myocardial infarction within the last 2 years, stroke, chronic obstructive pulmonary disease or cancer)
  • Immunodeficiency syndrome, active autoimmune or autoinflammatory disease (e.g. multiple sclerosis, lupus, rheumatoid arthritis), inflammatory bowel disease (e.g. IBS or ulcerative colitis) and acute episodes of atopic diseases (atopic dermatitis, asthma, type 1 allergies such as hay fever). Grave's disease, Hashimoto thyroiditis, Celiac disease, sarcoidosis, Lichen planus, are allowed, if well treated and stable
  • Regular intake of anticoagulants
  • Known allergy to any inactive or active ingredients in the study products
  • Participation in other clinical intervention trials during the study
  • Current or planned participation in a weight loss program (including intermittent fasting), extreme diet, or vigorous exercise (e.g., running, fast cycling, swimming laps, or playing intense sports that quickly raise your heart rate)

Treatment and study plan

Verum (A)

Dietary Supplement

1 capsule of A. muciniphila (pasteurized, initial quantity of 10^30 TFU, heat inactivated) and 1 capsule of 500 mg berberine hydrochloride per day.

Placebo (B)

Dietary Supplement

1 capsule of A. muciniphila placebo and 1 capsule of berberine placebo (both identical to verum regarding the shape, size, colour, and matched in excipients) per day.

Primary outcomes

  1. Change of 3-months supplementation with A. muciniphila and berberine on insulin resistance using HOMA-IR compared to placebo

    Time frame: At the beginning and the end of each intervention period (week 0, 12, 16, 28)

    Homeostasis Model Assessment of Insulin Resistance, calculated as (fasting insulin (μU/ml) x fasting glucose (mmol/l)) / 22.5, will be assessed to calculate the change between baseline and endpoint in the two periods

Secondary outcomes

  1. Change in gut microbiom composition between the baseline and endpoint change in the two periods

    Time frame: At the beginning and the end of each intervention period (week 0, 12, 16, 28)

    Gene sequencing of the 16S rRNA is performed on the stool samples to compare microbiota diversity and relative abundance

  2. Change in FABPi between the baseline and endpoint change in the two periods

    Time frame: At the beginning and the end of each intervention period (week 0, 12, 16, 28)

    Measurement of FABP intestinal (FABPi) in blood (pg/mL)

  3. Change in zonulin between the baseline and endpoint change in the two periods

    Time frame: At the beginning and the end of each intervention period (week 0, 12, 16, 28)

    Measurement of zonulin in blood (ng/mL)

  4. Change in LPB between the baseline and endpoint change in the two periods

    Time frame: At the beginning and the end of each intervention period (week 0, 12, 16, 28)

    Measurement of lipopolysaccharide-binding protein (LPB) in blood (pg/mL)

  5. Change in CRP between the baseline and endpoint change in the two periods

    Time frame: At the beginning and the end of each intervention period (week 0, 12, 16, 28)

    Analysis of high-sensitive C-reactive protein (hs-CRP, mg/L) in blood

  6. Change in stool short-chain fatty acids (SCFA) between the baseline and endpoint change in the two periods

    Time frame: At the beginning and the end of each intervention period (week 0, 12, 16, 28)

    SCFA will be extracted and quantitatively analysed by GC-MS (µmol/g)

  7. Change in blood lipid profile and cardiovascular markers between the baseline and endpoint change in the two periods

    Time frame: At the beginning and the end of each intervention period (week 0, 12, 16, 28)

    Measurement of cholesterol (mmol/L), low-density lipoprotein cholesterol (LDL-C, mmol/L), high-density lipoprotein (HDL-C, mmol/L), and triglyceride levels (TG, mmol/L) in blood

  8. Change in blood pressure between the baseline and endpoint change in the two periods

    Time frame: At the beginning and the end of each intervention period (week 0, 12, 16, 28)

    Systolic BP (mmHG) and diastolic BP (mmHG)

  9. Change in melatonin between the baseline and endpoint change in the two periods

    Time frame: At the beginning and the end of each intervention period (week 0, 12, 16, 28)

    6-sulfatoxymelatonin in urine (µg/L)

  10. Change in BMI between the baseline and endpoint change in the two periods

    Time frame: At the beginning and the end of each intervention period (week 0, 12, 16, 28)

    Body mass index (BMI)

  11. Change in body composition between the baseline and endpoint change in the two periods

    Time frame: At the beginning and the end of each intervention period (week 0, 12, 16, 28)

    Bioelectrical Impedance Analysis (BIA)

  12. Change in metabolomics at the end of the two periods

    Time frame: At the beginning and the end of each intervention period (week 12, week 28)

    Metabolomic profiles obtained with LC-MS/MS

Study contacts

Contact information is provided by the study sponsor or research team.

Miriam Ressler, PhD

CONTACT

[email protected]

+4331654536677

Sponsors and collaborators

Lead sponsor

FH Joanneum Gesellschaft mbH

Industry

Collaborators

  • Erasmus Medical Center
  • Københavns Universitet
  • Medical University of Vienna
  • University of Vienna

Registry information

Official study title

Effects of Akkermansia Muciniphila and Berberine Supplementation on Insulin Sensitivity in Night-shift Workers: a Double-blind, Randomised, Placebo-controlled, Crossover Study Within the Shift2Health Project

Acronym: Shift2Health

Important dates

Study start
2026
Primary completion
2027
Study completion
2028
First posted
Feb 27, 2026
Registry last updated
Feb 27, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.