Dietary sodium acetate and sodium butyrate improve high-carbohydrate diet utilization by regulating gut microbiota, liver lipid metabolism, oxidative stress, and inflammation in largemouth bass(Micropterus salmoides)

Background Adequate level of carbohydrates in aquafeeds help to conserve protein and reduce cost. However, studies have indicated that high-carbohydrate(HC) diet disrupt the homeostasis of the gut–liver axis in largemouth bass, resulting in decreased intestinal acetate and butyrate level.Method Herein, we had concepted a set of feeding experiment to assess the effects of dietary sodium acetate(SA) and sodium butyrate(SB) on liver health and the intestinal microbiota in largemouth bass fed an HC diet. The experimental design comprised 5 isonitrogenous and isolipidic diets, including LC(9% starch), HC(18% starch), HCSA(18% starch;2 g/kg SA), HCSB(18% starch;2 g/kg SB), and HCSASB(18% starch;1 g/kg SA + 1 g/kg SB). Juvenile largemouth bass with an initial body weight of 7.00 ± 0.20 g were fed on these diets for 56 d.Results We found that dietary SA and SB reduced hepatic triglyceride accumulation by activating autophagy(ATG101, LC3B and TFEB), promoting lipolysis(CPT1α, HSL and AMPKα), and inhibiting adipogenesis(FAS, ACCA, SCD1 and PPARγ). In addition, SA and SB decreased oxidative stress in the liver(CAT, GPX1α and SOD1) by activating the Keap1-Nrf2 pathway. Meanwhile, SA and SB alleviated HC-induced inflammation by downregulating the expression of pro-inflammatory factors(IL-1β, COX2 and Hepcidin1) through the NF-κB pathway. Importantly, SA and SB increased the abundance of bacteria that produced acetic acid and butyrate(Clostridium_sensu_stricto_1). Combined with the KEGG analysis, the results showed that SA and SB enriched carbohydrate metabolism and amino acid metabolism pathways, thereby improving the utilization of carbohydrates. Pearson correlation analysis indicated that growth performance was closely related to hepatic lipid deposition, autophagy, antioxidant capacity, inflammation, and intestinal microbial composition.Conclusions In conclusion, dietary SA and SB can reduce hepatic lipid deposition;and alleviate oxidative stress and inflammation in largemouth bass fed on HC diet. These beneficial effects may be due to the altered composition of the gut microbiota caused by SA and SB. The improvement effects of SB were stronger than those associated with SA.

Low Carbohydrate Diets in Type 2 Diabetes—A Translational Study

Although intensive interventions with low carbohydrate diets compared with higher carbohydrate diets can reduce HbA1c in people with type 2 diabetes, it is not clear if simple advice to make modest reductions in carbohydrate is effective in clinical practice. Forty-three people with type 2 diabetes and poor control (HbA1c > 7.5%) were randomized to receive 2 short education sessions over 6 months with a non-dietitian researcher on how to reduce carbohydrate intake by about 25% or to 2 control sessions in which the Australian Guide to Healthy Eating was provided. Hba1c and fasting glucose and lipids were measured at baseline and 3 months and 6 months. 33 volunteers attended a baseline visit;27 completed 3 months and 24 6 months. HbA1c was reduced by 0.6% - 0.7% in the low carbohydrate diet group compared with the control group (P = 0.1). Fasting glucose was reduced by 2.3 mmol/L compared with the control group at 3 months (P < 0.03) only. Changes in HbA1c at 6 months were related to baseline HbA1c in the intervention group only. Although we have obtained suggestive evidence that a low carbohydrate diet can be successfully implemented in normal practice without professional help, our results are limited by low participant numbers and further studies are required.

Dietary sodium acetate and sodium butyrate attenuate intestinal damage and improve lipid metabolism in juvenile largemouth bass(Micropterus salmoides)fed a high carbohydrate diet by reducing endoplasmic reticulum stress

High-carbohydrate(HC)diets decrease the intestinal levels of sodium acetate(SA)and sodium butyrate(SB)and impair the gut health of largemouth bass;however,SA and SB have been shown to enhance immunity and improve intestinal health in farmed animals.Thus,the present study was to investigate the effects of dietary SA and SB on HC diet-induced intestinal injury and the potential mechanisms in juvenile largemouth bass.The experiment set five isonitrogenous and isolipidic diets,including a lowcarbohydrate diet(9%starch)(LC),a high carbohydrate diet(18%starch)(HC),and the HC diet supplemented with 2 g/kg SA(HCSA),2 g/kg SB(HCSB)or a combination of 1 g/kg SA and 1 g/kg SB(HCSASB).The feeding experiment was conducted for 8 weeks.A total of 525 juvenile largemouth bass with an initial body weight of 7.00±0.20 g were used.The results showed that dietary SA and SB improved the weight gain rate and specific growth rate(P<0.05)and ameliorated serum parameters(alkaline phosphatase,acid phosphatase,glutamate transaminase,and glutamic oxaloacetic transaminase)(P<0.05).And,importantly,dietary SA and SB repaired the intestinal barrier by increasing the expression levels of zonula occludens-1,occludin,and claudin-7(P<0.05),reduced HC-induced intestinal damage,and alleviated intestinal inflammation and cell apoptosis by attenuating HC-induced intestinal endoplasmic reticulum stress(P<0.05).Further results revealed that dietary SA and SB reduced HC-induced intestinal fat deposition by inhibiting adipogenesis and promoting lipolysis(P<0.05).In summary,this study demonstrated that dietary SA and SB attenuated HC-induced intestinal damage and reduced excessive intestinal fat deposition in largemouth bass.

Restricting carbohydrates to fight head and neck cancer——is this realistic?

Head and neck cancers(HNCs) are aggressive tumors that typically demonstrate a high glycolytic rate, which results in resistance to cytotoxic therapy and poor prognosis. Due to their location these tumors specifically impair food intake and quality of life, so that prevention of weight loss through nutrition support becomes an important treatment goal. Dietary restriction of carbohydrates(CHOs) and their replacement with fat, mostly in form of a ketogenic diet(KD), have been suggested to accommodate for both the altered tumor cell metabolism and cancer-associated weight loss. In this review, I present three specific rationales for CHO restriction and nutritional ketosis as supportive treatment options for the HNC patient. These are(1) targeting the origin and specific aspects of tumor glycolysis;(2) protecting normal tissue from but sensitizing tumor tissue to radiation- and chemotherapy induced cell kill;(3) supporting body and muscle mass maintenance. While most of these benefits of CHO restriction apply to cancer in general, specific aspects of implementation are discussed in relation to HNC patients. While CHO restriction seems feasible in HNC patients the available evidence indicates that its role may extend beyond fighting malnutrition to fighting HNC itself.

Assessing the evidence for weight loss strategies in people with and without type 2 diabetes

This review will examine topical issues in weight loss and weight maintenance in people with and without diabetes. A high protein, low glycemic index diet would appear to be best for 12-mo weight maintenance in people without type 2 diabetes. This dietary pattern is currently beingexplored in a large prevention of diabetes intervention. Intermittent energy restriction is useful but no better than daily energy restriction but there needs to be larger and longer term trials performed. There appears to be no evidence that intermittent fasting or intermittent severe energy restriction has a metabolic benefit beyond the weight loss produced and does not spare lean mass compared with daily energy restriction. Meal replacements are useful and can produce weight loss similar to or better than food restriction alone. Very low calorie diets can produce weight loss of 11-16 kg at 12 mo with persistent weight loss of 1-2 kg at 4-6 years with a very wide variation in long term results. Long term medication or meal replacement support can produce more sustained weight loss. In type 2 diabetes very low carbohydrate diets are strongly recommended by some groups but the long term evidence is very limited and no published trial is longer than 12 mo. Although obesity is strongly genetically based the microbiome may play a small role but human evidence is currently very limited.