Dietary supplementation of ark clams protects gut health and modifies gut microbiota in d-galactose-induced aging rats.

BACKGROUND: Ark clams, a seafood abundant in various nutrients, are widely consumed worldwide. This study aimed to investigate the protective benefits of two common ark clams in Korea, Scapharca subcrenata (SS) and Tegillarca granosa (TG), on gut health in d-galactose (d-gal)-induced aging rats. RESULTS: Thirty-two Wistar rats (11 weeks old) were randomly allocated into four groups: a CON group (normal diet + saline intraperitoneal (i.p.) injection), a CD group (normal diet + d-gal i.p. injection), an SS group (normal diet with 5% SS supplementation + d-gal i.p. injection), and a TG group (normal diet with 5% TG supplementation + d-gal i.p. injection). After 12 weeks of treatment, histopathological results showed that gut barrier damage was alleviated in rats of the SS and TG groups, as evidenced by increases in mucus layer thickness and goblet cell numbers. Meanwhile, the two groups supplemented with ark clams showed an evident reduction in oxidative stress biomarkers (malondialdehyde and protein carbonyl content levels in the colon) and an increase in the immune-related factor (immunoglobulin A level in the plasma) in rats. The 16S ribosomal RNA analysis revealed that SS and TG ark clams significantly increased the proliferations of Bacteroidetes at the phylum level and Parabacteroides at the genus level. Additionally, the levels of the three main short-chain fatty acids in the cecal contents were also significantly increased in the SS and TG groups. CONCLUSION: Our results indicated a potent preventive effect of SS and TG ark clams on d-gal-induced gut injury, suggesting that ark clams may be a promising dietary component for intervening in aging. © 2023 Society of Chemical Industry.

Dietary Supplementation of Cedryl Acetate Ameliorates Adiposity and Improves Glucose Homeostasis in High-Fat Diet-Fed Mice.

Cedryl acetate (CA), also called acetyl cedrene, is approved by the FDA as a flavoring or adjuvant to be added to foods. In this study, we aimed to investigate the preventive benefits of CA on obesity and obesity-related metabolic syndrome caused by a high-fat diet (HFD). Three groups of C57BL/6J mice (ten-week-old) were fed Chow, an HFD, or an HFD with CA supplementation (100 mg/kg) for 19 weeks. We observed that CA supplementation significantly reduced weight gain induced by an HFD, decreased the weight of the visceral fat pads, and prevented adipocyte hypertrophy in mice. Moreover, mice in the CA group showed significant improvements in hepatic lipid accumulation, glucose intolerance, insulin resistance, and gluconeogenesis compared with the mice in the HFD group. Since 16S rRNA analysis revealed that the gut microbiota in the CA and HFD groups were of similar compositions at the phylum and family levels, CA may have limited effects on gut microbiota in HFD-fed mice. The beneficial effects on the metabolic parameters of CA were reflected by CA's regulation of metabolism-related gene expression in the liver (including Pepck, G6Pase, and Fbp1) and the epididymal white adipose tissues (including PPARγ, C/EBPα, FABP4, FAS, Cytc, PGC-1α, PRDM16, Cidea, and COX4) of the mice. In summary, a potent preventive effect of CA on HFD-induced obesity and related metabolic syndrome was highlighted by our results, and CA could be a promising dietary component for obesity intervention.