Chaiwat Boonkaewwan

Anti-inflammatory and immunomodulatory activities of stevioside and steviol on colonic epithelial cells.

BACKGROUND Stevioside is a natural non-caloric sweetener isolated from Stevia rebaudiana Bertoni leaves. We have proposed its effect on attenuation of tumour necrosis factor α (TNF-α) and interleukin 1β (IL-1β) release in lipopolysaccharide (LPS)-stimulated monocytes. In this study, the anti-inflammatory and immunomodulatory activities of stevioside and its metabolite, steviol, on human colon carcinoma cell line (Caco-2) were evaluated. RESULTS Stevioside and steviol, in the doses used in this study, had no cytotoxicity on Caco-2 cells. Anti-inflammatory activities of these two compounds were observed by potentially suppressed LPS-mediated TNF-α, IL-1β and IL-6 release. In addition, stevioside and steviol showed immunomodulatory effects on IκBα activation and nuclear factor kappa B (NF-κB) suppression in western blotting. CONCLUSION Stevioside and steviol attenuate LPS-induced pro-inflammatory cytokine productions by affecting cytokine gene expression via IκBα/NF-κB signalling pathway.

Breed-related number and size of muscle fibres and their response to carcass quality in chickens

The present study was aimed to investigate the number and size of muscle fibre and their relation to carcass quality traits in chickens (slow- and fast-growing chicken strains). A total of 40 one-day-old Arbor Acres broiler (fast-growing) and 40 Thai native chickens (slow-growing) were reared to 45 and 112 days, respectively. The Arbor Acres broilers had heavier live weight, higher breast and thigh percentage than Thai native chickens (P<0.001). In breast muscle, there was no significant difference in total number of fibres and perimysium thickness. Thai native chickens had smaller fibre diameter and fibre area (P<0.01), and thicker endomysium in comparison with Arbor Acres broiler (P<0.001). The difference between the thigh and breast muscle fibre characteristics was not significant (P>0.05). The fibre diameter was positively correlated with live weight (P<0.05) and breast percentage (P<0.01). Endomysium thickness was correlated with live weight and breast percentage (P<0.05). There was no significant difference for the correlation between muscle fibre characteristics and thigh muscle. These results suggest that muscle fibre characteristics might be related to carcass quality.

Blood haematology, muscle pH and serum cortisol changes in pigs with different levels of drip loss

Objective An experiment was conducted to study the blood haematology, muscle pH, and serum cortisol changes in pigs with different levels of drip loss. Methods Two groups (low and high) of 20 animals were selected from 100 pigs based on drip loss. All [Duroc× (Large White×Landrace)] pigs were slaughtered according to standard slaughtering procedures. At exsanguinations, blood samples were taken for the haematological parameters and serum cortisol analysis. The muscle samples were taken from longissimus dorsi muscle to evaluate the muscle pH and drip loss. Results Haematological parameters of low drip loss group showed higher content of white blood cells and monocytes than high drip loss group (p<0.05). The low drip loss group had higher muscle pH at 45 min (p<0.05) and 24 h (p<0.001) post-mortem than the high drip loss group. However, there was no significant difference in serum cortisol levels (p>0.05). Conclusion Drip loss is mainly affected by the muscle pH decline after slaughter and also might be affected by white blood cells and monocytes.