Modulating gut microbiota composition through probiotic administration has been proposed as a novel therapy for type 2 diabetes mellitus (T2DM), and fermented milk is arguably the most common and ideal probiotic carrier. The present meta-analysis was performed to assess the effects of probiotic fermented milk supplementation on glucose and lipid metabolism parameters and inflammatory markers in patients with T2DM using published data from randomized controlled trials (RCTs). The PubMed, Web of Science, and Cochrane Library databases were searched for relevant RCTs. A random-effects model was used to generate the weighted mean difference (WMD) and 95% confidence interval (95% CI). Probiotic fermented milk supplementation reduced the levels of fasting plasma glucose (MD = −17.01, 95% CI −26.43, −7.58 mg/dL; n = 7), hemoglobin A1c (MD = −0.47, 95% CI −0.74, −0.21%; n = 7), total cholesterol (MD = −5.15, 95% CI −9.52, −0.78 mg/dL; n = 7), and C-reactive protein (MD = −0.25, 95% CI −0.43, −0.08; n = 3) but did not significantly affect the levels of HOMA-IR (MD = −0.89, 95% CI −2.55, 0.78; n = 3), triglyceride (MD = −4.69, 95% CI −14.67, 5.30 mg/dL; n = 6), low-density lipoprotein cholesterol (MD = −4.25, 95% CI −8.63, 0.13 mg/dL; n = 7), high-density lipoprotein cholesterol (MD = 1.20, 95% CI −0.96, 3.36 mg/dL; n = 7), and tumor necrosis factor-alpha (MD: −0.58, 95% CI −1.47, 0.32 pg/mL; n = 2). In summary, the present findings provide a crude indication of the potential benefits of probiotic fermented milk supplementation in improving glucose and lipid metabolism and inflammation in patients with T2DM. However, more robust evidence is needed to determine the clinical significance of probiotic fermented milk in the management of T2DM.

Short peptides have gained widespread utilization as functional constituents in the development of functional foods due to their remarkable biological activity. Previous investigations have established the positive influence of oysters on testosterone biosynthesis, although the underlying mechanism remains elusive. This study aims to assess the impact of three dipeptides derived from oysters on the oxidative stress state of TM3 cells induced by AAPH while concurrently examining alterations in cellular testosterone biosynthesis capacity. The investigation encompasses an analysis of reactive oxygen species (ROS) content, antioxidant enzyme activity, apoptotic status, and expression levels of crucial enzymes involved in the testosterone synthesis pathway within TM3 cells, thus evaluating the physiological activity of the three dipeptides. Additionally, molecular docking was employed to investigate the inhibitory activity of the three dipeptides against ACE. The outcomes of this study imply that the oxidative stress state of cells impedes the synthesis of testosterone by inhibiting the expression of essential proteins in the testosterone synthesis pathway. These three dipeptides derived from oysters ameliorate cellular oxidative stress by directly scavenging excess ROS or reducing ROS production rather than enhancing cellular antioxidant capacity through modulation of antioxidant enzyme activity. These findings introduce a novel avenue for developing and utilizing antioxidant peptides derived from food sources.

Excessive ultraviolet A (UVA) irradiation disrupts extracellular matrix (ECM) homeostasis in skin photoaging by impairing the balance between synthesis and degradation, yet whether silk fibroin peptide (SF), a small bioactive peptide from Bombyx mori, can restore this balance through mechanotransduction pathways remains unknown. Herein, we demonstrate that SF dose-dependently rescues human dermal fibroblasts (HDFs) from UVA-induced oxidative stress, senescence, and ECM disintegration. Notably, SF not only suppresses reactive oxygen species (ROS) and restores activities of antioxidant enzymes, but is also associated with the recovery of the ITGB1-FAK mechanotransduction axis, as evidenced by restored fibronectin levels and increased focal adhesion kinase (FAK) phosphorylation, whereas integrin β1 (ITGB1) expression itself was not significantly altered. This mechanosensory recovery is accompanied by restoration of downstream transforming growth factor-β (TGF-β)/Smad signaling, upregulation of COL1A1, COL3A1 and ELN transcription, and simultaneous suppression of MMP1, MMP3 and MMP9. Unlike conventional antioxidants or exogenous collagen supplements that merely counteract oxidative damage or provide structural substitutes, SF may facilitate recovery of the disrupted cell–matrix interface potentially through modulation of integrin-mediated mechanochemical signal conversion, which may contribute to ECM homeostasis restoration. Collectively, SF promotes mechanotransduction, offering a potential paradigm for anti-aging strategies that target ECM homeostasis through integrin signaling.