RESEARCH ARTICLE Green Tea and Decaffeinated Light Roasted Green Coffee Extract Combination Improved Cardiac Insulin Resistance through Free Fatty Acids and Adiponectin/FAS Pathway Amelioration in Metabolic Syndrome Rat Model [version 1; peer review: awaiting peer review] Mifetika Lukitasari 1 , Mohammad Saifur Rohman 2 , Dwi Adi Nugroho 3 , Mukhamad Nur Kholis 4 , Nila Aisyah Wahyuni 4 , Nashi Widodo 5 1 Department of Nursing, Faculty of Medicine, Brawijaya University, Malang, East java, +62, Indonesia 2 Department of Cardiology and Vascular Medicine, Faculty of Medicine, Brawijaya University, Malang, East java, +62, Indonesia 3 Department of Herbal Medicine, Brawijaya Cardiovascular Research Group, Faculty of Medicine, Brawijaya University, Malang, East java, +62, Indonesia 4 Magister of Biomedical Sciences, Faculty of Medicine, Brawijaya University, Malang, East java, +62, Indonesia 5 Department of Biology Mathematics and Natural Sciences, Brawijaya, Malang, East java, +62, Indonesia First published: 30 Sep 2021, 10:990 https://doi.org/10.12688/f1000research.55470.1 Latest published: 30 Sep 2021, 10:990 https://doi.org/10.12688/f1000research.55470.1 v1 Abstract Background: Insulin resistance has been independently associated with cardiac diseases. A free fatty acid is recently known to induce cardiac insulin resistance due to low-grade inflammation. Therefore, the improvement of free fatty acid levels can also improve cardiac insulin resistance. This study investigated the combination of green tea and decaffeinated-light roasted green coffee extract in improvement of free fatty acid-induced cardiac insulin resistance by improving the adiponectin/FAS pathway. Methods: This study used 25 males Sprague-Dawley rats induced by a high-fat high sucrose diet and injection of low dose streptozotocin to make a metabolic syndrome (MS) rat model and standard chow as healthy control rats. The MS rats were treated with green tea (200 mg/ b. w.), decaffeinated-light roasted green coffee (300 mg/ b. w.), and the combination of both extracts in 9 weeks. Experimental groups in this study were divided into 5 groups: 1) MS (HFHS diet + STZ) group, 2) NC (normal chow) group, 3) GT (green tea extract) group, 4) GC (decaffeinated-light roasted green coffee extract), 5) CM (combination of both extracts) group. Adiponectin and HOMA-IR level was analysed using ELISA, and the gene expression of Adipo-R1, FAS, PI3K, PDK1, Akt, GLUT4 was measured by RT-PCR. Results: The combination of green tea and decaffeinated-light Open Peer Review Reviewer Status AWAITING PEER REVIEW Any reports and responses or comments on the article can be found at the end of the article. Page 1 of 13 F1000Research 2021, 10:990 Last updated: 30 SEP 2021