Antidiabetic Effects of Coffee Enriched with Maca and Marine Collagen Peptide (Blackbelt®) in a Type 2 Diabetes Mellitus Rat Model

INTRODUCTION: The International Diabetes Federation (IDF) reported 463 million global cases of Type 2 diabetes mellitus (T2DM) in 2019. Lepidium meyenii (maca) and marine collagen peptide (MCP) have individually shown potential in alleviating T2DM symptoms, but their combined effects remain underexplored. This study evaluated the impact of Blackbelt® coffee, enriched with maca and MCP, on fasting blood glucose, insulin levels, and pancreatic and liver histology in a T2DM rat model. MATERIALS AND METHODS: Thirty-six male rats with a high-fat diet and streptozotocin-induced diabetes were treated with metformin, maca, MCP, Maca/MCP® (Blackbelt® formulation), or Blackbelt® coffee for 28 days. Fasting blood glucose (FBG) levels were monitored, and fasting serum insulin, HOMA-IR (insulin resistance), HOMA-B (ß-cell function), and QUICKI (insulin sensitivity) were assessed. Histological analysis of the pancreas and liver was performed using haematoxylin-eosin staining. RESULTS: After 4 weeks, treatments significantly reduced FBG levels compared to control (p<0.05), with Blackbelt® coffee notably increasing insulin production (p<0.05). All groups showed decreased HOMA-IR (p<0.05), and both metformin and Blackbelt® coffee groups had significant HOMA-B score increases (p<0.05). Histological analysis revealed improved pancreatic health in all treated groups, with significant liver histology enhancement in the Blackbelt® coffee group. CONCLUSIONS: Blackbelt® coffee improved FBG levels, insulin resistance, and ß-cell function more effectively than maca or MCP alone, and surpassed metformin in insulin production and hepatoprotective effects. Despite its promising potential for diabetes therapy, further research is needed to understand the synergistic effects of maca and MCP and the contribution of the coffee components.