Akkermansia muciniphila improves heat stress-impaired intestinal barrier function by modulating HSP27 in Caco-2 cells.

OBJECTIVE: Heat stress causes an elevation of intestinal epithelial barrier permeability and leads to multiple organ dysfunction in heatstroke. Akkermansia muciniphila (A. muciniphila) plays a role in maintaining intestinal integrity and improving the inflammatory state. This study aimed to investigate whether A. muciniphila could alleviate heat stress-induced dysfunction of intestinal permeability in Caco-2 monolayers and have the preventive effects on heatstroke. METHODS: Human intestinal epithelial Caco-2 cells were preincubated with live or pasteurized A. muciniphila then exposed to heat stress at 43 °C. Transepithelial electrical resistance (TEER) and the flux of horseradish peroxidase (HRP) across cell monolayers were measured to determine intestinal permeability. The levels of the tight junction proteins Occludin, ZO-1 and HSP27 were analyzed by Western blotting. These proteins were immunostained and localized by fluorescence microscopy. TJ morphology was observed using transmission electron microscopy (TEM). RESULTS: Both live and pasteurized A. muciniphila effectively attenuated the decrease in TEER and impairment of intestinal permeability in HRP flux induced by heat exposure. A. muciniphila significantly elevated the expression of Occludin and ZO-1 by promoting HSP27 phosphorylation. The distortion and redistribution of tight junction proteins and disruption of morphology were also effectively prevented by pretreatment with A. muciniphila. CONCLUSION: This study indicates for the first time that both live and pasteurized A. muciniphila play an important protective role against heat-induced permeability dysfunction and epithelial barrier damage.

Gastric emptying of preoperative drinks is slower in adults with chronic energy deficiency: A 2 hour cross-over study among Chinese.

BACKGROUND AND OBJECTIVES: To investigate the effects of oral preoperative regimens on gastric emptying time in relation to BMI in Chinese adults. METHODS AND STUDY DESIGN: The enrolled 56 adults were divided into three groups (normal-weight, underweight, and overweight) and completed a regimen of two drinks after a 2-week interval. After drinking a carbohydrate regimen (CD, 50 g carbohydrates) or a carbohydrate glutamine regimen (CGD, 44 g carbohydrates and 6 g glutamine) labelled with 99mTc-DTPA (99mTc-diethylenetriaminepentaacetic acid), gastric emptying times T50 and T90 were measured using a curve derived from scintigraphic images. RESULTS: T50 and T90 had no significant difference between the CD and CGD regimens. T50 was significantly delayed in the underweight participants (BMI <18.5 kg/m2, as Chronic Energy Deficiency, CED) compared with the normal-weight participants after drinking CD (p=0.003) or CGD (p=0.002), as well as T90 after CD (p=0.019). There was no difference in glucose concentrations between the three groups. There are negative correlations between body weight and gastric emptying time T50 (r=-0.461, p=0.016) or T90 (r=-0.553, p=0. 003) after drinking CD, as well as T50 (r=-0.553, p=0.003) after drinking CGD. CONCLUSIONS: Underweight adults should be careful to take oral preoperative regimens 2 hours before surgery and consider reducing the volume because of a slower gastric emptying rate.

Comparing the measured basal metabolic rates in patients with chronic disorders of consciousness to the estimated basal metabolic rate calculated from common predictive equations.

BACKGROUND: Accurately predicting the basal metabolic rate (BMR) of patients in a vegetative state (VS) or minimally conscious state (MCS) is critical to proper nutritional therapy, but commonly used equations have not been shown to be accurate. Therefore, we compared the BMR measured by indirect calorimetry (IC) to BMR values estimated using common predictive equations in VS and MCS patients. METHODS: Body composition variables were measured using the bioelectric impedance analysis (BIA) technique. BMR was measured by IC in 82 patients (64 men and 18 women) with VS or MCS. Patients were classified by body mass index as underweight (<18.5 kg/m2, n = 34) or normal-weight (18.5 ≤ BMI < 25 kg/m2, n = 48). BMR was estimated for each group using the Harris-Benedict (H-B), Schofield, or Cunningham equations and compared to the measured BMR using Bland-Altman analyses. RESULTS: For the underweight group, there was a significant difference between the measured BMR values and the estimated BMR values calculated using the H-B, Schofield, and Cunningham equations (p < 0.05). For the normal-weight group, the BMR values estimated using the H-B and Cunningham equations were different significantly from the measured BMR (p < 0.05 and p < 0.01 respectively). Of the predictive equations, only Schofield was not significantly different from the measured BMR in the normal-weight group. The Schofield equation showed the best concordance (only 41.5%) with the BMR values measured by IC. CONCLUSIONS: None of the commonly used equations to estimate BMR were suitable for the VS or MCS populations. Indirect calorimetry is the preferred way to avoid either over or underestimate of BMR values.